Consumer Research on Infant Formula and Infant Feeding

Below are research abstracts of consumer research studies conducted or supported by the Center for Food Safety and Applied Nutrition.  

A Longitudinal Analysis of Infant Morbidity and the Extent of Breastfeeding in the United States.
1997. Paula D. Scariati, Laurence M. Grummer-Strawn and Sara B. Fein. Pediatrics 99(6):e5 (Electronic Article)

BACKGROUND: Studies on the health benefits of breastfeeding in developed countries have shown conflicting results. These studies often fail to account for confounding, reverse causality, and dose-response effects. We addressed these issues in analyzing longitudinal data to determine if breastfeeding protects US infants from developing diarrhea and ear infections.
METHODS: Mothers participating in a mail panel provided information on their infants at ages 2, 3, 4, 5, 6, and 7 months. Infants were classified as exclusively breastfed; high, middle, or low mixed breast-and formula-fed; or exclusively formula-fed. Diarrhea and ear infection diagnoses were based on mothers' reports. Infant age and gender; other liquid and solid intake; maternal education, occupation, and smoking; household size; family income; and day care use were adjusted for in the full models.
RESULTS: The risk of developing either diarrhea or ear infection increased as the amount of breast milk an infant received decreased. In the full models, the risk for diarrhea remained significant only in infants who received no breast milk compared with those who received only breast milk (odds ratio = 1.8); the risk for ear infection remained significant in the low mixed feeding group (odds ratio = 1.6) and among infants receiving no breast milk compared with those who received only breast milk (odds ratio = 1.7).
CONCLUSIONS: Breastfeeding protects US infants against the development of diarrhea and ear infection. Breastfeeding does not have to be exclusive to confer this benefit. In fact, protection is afforded in a dose-response manner. The more breast milk an infant receives in the first 6 months of life, the less likely that he or she will develop diarrhea or ear infection.

Risk of Diarrhea Related to Iron Content of Infant Formula: Lack of Evidence to support the Use of Low-iron Formula as a supplement for Breastfed Infants. 1997. Paula D. Scariati, Laurence M. Grummer-Strawn, Sara B. Fein, and Ray Yip. Pediatrics 99(3):e2.
BACKGROUND: Concern has been raised by infant feeding experts that supplementing breastfed infants with iron-fortified formula rather than low-iron formula may have an undesirable impact on their gastrointestinal flora. Thus far, there have been no clinical studies to address this issue directly. We compared the reported frequency of diarrhea for breastfed infants given iron-fortified formula with those fed low-iron formula.
METHODS: Mothers participating in a mail panel provided feeding and diarrhea information on their infants at 2, 3, 4, 5, 6, 7, 9, and 12 months (n = 1743). Infants were grouped into five feeding categories: (1) breast milk only, (2) breast milk and low-iron formula, (3) breast milk and iron-fortified formula, (4) low-iron formula only, and (5) iron-fortified formula only. We calculated the number of diarrheal episodes per week for each feeding category and used rate ratios to estimate the relative impact of low-iron and iron-fortified formulas.
RESULTS: Among infants who received both breast milk and formula, the rate ratio for iron-fortified formula versus low-iron formula was 1.06 (confidence interval, 0.84 to 1.34), indicating that the type of formula a breastfed infant receives does not significantly affect the frequency of diarrhea.
CONCLUSIONS: We found no evidence to support the hypothesis that breastfed infants given iron-fortified formula are at greater risk of having diarrhea. This, in addition to the fact that iron-fortified formula has played a major role in preventing childhood iron deficiency anemia, supports the current recommendation that any formula given to infants be fortified with iron. food, diarrhea, breastfeeding, iron.

Water Supplementation of Infants in the First Month of Life. 1997. Paula D. Scariati, DO, MPH, Laurence M. Grummer-Strawn, PhD; Sara B. Fein, PhD. Archives of Pediatrics & Adolescent Medicine 151:830-832.
OBJECTIVE: To describe the prevalence of and risk factors associated with regular water supplementation of neonates, considering infant feeding status, mother's education, and family income.
DESIGN: Evaluation of data from the Food and Drug Administration's Infant Feeding Practices Study, a panel study of US women of fairly high socioeconomic status who were followed up from late pregnancy through their infants' first year of life. The sample was drawn from a nationally distributed consumer mail panel. Each mother was asked whether she gave her neonate water at least 3 times per week.
PARTICIPANTS: A total of 1677 mothers of infants who were neonates in April through November 1993.
Main Outcome Measures: Percentages of mothers who gave their neonates water at least 3 times a week.
RESULTS: About one fourth (24.7%) of the mothers reported giving their neonates water at least 3 times per week. Stratification by feeding practices and socioeconomic factors revealed that 41.6% of mothers who formula-fed their neonates, 47.4% of mothers with less than a high school education, and 35.4% of mothers with an annual family income less than $22,500 gave their neonates water at least 3 times per week.
CONCLUSIONS: Water supplementation of neonates was a prevalent practice in this cohort of women. Feeding practices, maternal education, and family income were all significant risk factors associated with this behavior.

The Effect of Work Status on Initiation and Duration of Breast-Feeding. 1998. Sara B. Fein, PhD, and Brian Roe, PhD. A. American Journal of Public Health 88:1042-1046
OBJECTIVES: In this study, longitudinal data are used to examine the effect of work status on breast-feeding initiation and duration.
METHODS: Mothers from a mail panel completed questionnaires during late pregnancy and 10 times in the infant's first year. Mother's work status was categorized for initiation by hours she expected, before delivery to work and for duration by hours she worked at month 3. Covariates were demographics, parity, medical, delivery, and hospital experiences, social support, embarrassment, and health promotion.
RESULTS: Expecting to work part-time neither decreased nor increased the probability of breast-feeding relative to expecting not to work (odds ratios [ORs] =.83 and .99, P>.50), but expecting to work full-time decreased the probability of breast-feeding (OR= .47, P < .0l). Working full-time at 3 months postpartum decreased breast feeding duration by an average of 8.6 weeks (P<.001) relative to not working, but part-time work of 4 or fewer hours per day did not affect duration, and part-time work of more than 4 hours per day decreased duration less than full-time work.
CONCLUSION: Part-time work is an effective strategy to help mothers combine breast-feeding and employment.

Is There Competition Between Breast-Feeding and Maternal Employment? 1999. Brian Roe, Leslie A. Whittington, Sara Beck Fein, and Mario F. Teisl. Demography 36(2):157-171.
Theory suggests that the decision to return to employment after childbirth and the decision to breast-feed may be jointly determined. We estimate models of simultaneous equations for two different aspects of the relationship between maternal employment and breastfeeding using 1993-1994 data from the U.S. Food and Drug Administration's Infant Feeding Practices Study. We first explore the simultaneous duration of breast-feeding and work leave following childbirth. We find that the duration of leave from work significantly affects the duration of breast-feeding, but the effect of breastfeeding on work leave is insignificant. We also estimate models of the daily hours of work and breast feedings at infant ages 3 months and 6 months postpartum. At both times, the intensity of work effort significantly affects the intensity of breast-feeding, but the reverse is generally not found. Competition clearly exists between work and breast-feeding for many women in our sample.

Medically Advised, Mother's Personal Target, and Actual Weight Gain During Pregnancy. 1999. Mary E. Cogswell, Kelley S. Scanlon, Sara Beck Fein, and Laura A. Schieve. Obstetrics and Gynecology 94(4):616-622.
OBJECTIVE: To evaluate whether advice on pregnancy weight gain from health care professionals, women's target weight gain (how much weight women thought they should gain), and actual weight gain corresponded with the 1990 Institute of Medicine recommendations.
METHODS: Predominantly white, middle-class women participating in a mail panel reported their prepregnancy weights, heights, and advised and target weight gains on a prenatal questionnaire (n = 2237), and their actual weight gains on a neonatal questionnaire (n = 1661). Recommended weight gains were categorized for women with low body mass index (BMI) (less than 19.8 kg/m2) as 25-39 lb; for women with average BMI (19.8-26.0 kg/m2) as 25-34 lb; and for women with high BMI (more than 26.0-29.0 kg/m2) and very high BMI (more than 29.0 kg/m2) as 15-24 lb.
RESULTS: Twenty-seven percent of the women reported that they had received no medical advice about pregnancy weight gain. Among those who received advice, 14% (95% confidence interval 1CIl 12%, 16%) had been advised to gain less than the recommended range and 22% (95% Cl 20%, 24%) had been advised to gain more than recommended. The odds of being advised to gain more than recommended were higher among women with high BMIs and with very high BMIs compared with women with average BMIs. Black women were more likely than white women to report advice to gain less than recommended. Advised and target weight gains were associated strongly with actual weight gain. Receiving no advice was associated with weight gain outside the recommendations.
CONCLUSION: Greater efforts are required to improve medical advice about weight gain during pregnancy.

Infant Feeding Practices Study II: Study Methods. 2008. Fein, Sara B., Judith Labiner-Wolfe, Katherine Shealy, Ruowei Li, Jian Chen, Laurence M. Grummer-Strawn. Pediatrics 122(suppl 2): S28-S35.
OBJECTIVE: Our goal is to describe the methods used in the Infant Feeding Practices
Study II (IFPS II), a study of infant feeding and care practices throughout the first year of life. Survey topics included breastfeeding, formula and complementary feeding, infant health, breast-pump use, food allergies, sleeping arrangements, mother’s employment, and child care arrangements. In addition, mothers’ dietary intake was measured prenatally and postnatally.
PARTICIPANTS AND METHODS: The IFPS II sample was drawn from a nationally distributed consumer opinion panel of 500 000 households. All questionnaires were administered by mail, 1 prenatally and 10 postpartum. Qualifying criteria were used to achieve the sample goals of mothers of healthy term and late preterm singleton infants. In addition to the questionnaires about the infants, women were sent a diet-assessment questionnaire prenatally and at 4 months after delivery; this questionnaire was also sent to members of a comparison group who were neither pregnant nor postpartum.
RESULTS: A sample of 4902 pregnant women began the study, and 2000 continued through their infant’s first year. Response rates ranged from 63% to 87% for the different questionnaires. Compared with adult mothers of singletons from the nationally representative sample of the National Survey of Family Growth, IFPS II participants had a higher mean education level; were older; were more likely to be middle income, white, and employed; were less likely to smoke; and had fewer other children. Compared with women who participated in the National Immunization Survey who gave birth in 2004, IFPS II mothers were more likely to breastfeed and to breastfeed longer.
CONCLUSIONS: The IFPS II provides a valuable database because of its large sample size, the frequency of its questionnaires, and its wide coverage of issues salient to infant feeding.

Infant Feeding and Feeding Transitions during the First Year of Life. 2008. Grummer-Strawn, Laurence M., Kelley S. Scanlon, Sara B. Fein. Pediatrics 122(suppl 2): S36-S42.
OBJECTIVE: Infancy is a time of rapid transition from a diet of virtually nothing but milk (either breast milk or infant formula) to a varied diet from nearly all food groups being consumed on a daily basis by most infants. Despite various recommendations about infant feeding, little is known about actual patterns of feeding among US infants. This article documents transitions in infant feeding patterns across the first year of life and determinants of key aspects of infant feeding.
METHODS: Using data from the Infant Feeding Practices Study II, we analyzed responses to a 7-day food-recall chart that was administered every month. The sample size declined from 2907 at birth to 1782 at 12 months of age.
RESULTS: Although 83% of survey respondents initiated breastfeeding, the percentage who breastfed declined rapidly to 50% at 6 months and to 24% at 12 months. Many of the women who breastfed also fed their infants formula; 52% reported that their infants received formula while in the hospital. At 4 months, 40% of the infants had consumed infant cereal, 17% had consumed fruit or vegetable products, and <1% had consumed meat. Compared with infants who were not fed solid foods at 4 months, those who were fed solid foods were more likely to have discontinued breastfeeding at 6 months (70% vs 34%) and to have been fed fatty or sugary foods at 12 months (75% vs 62%).
CONCLUSIONS: Supplementing breast milk with infant formula while infants were still in the hospital was very common. Despite recommendations that complementary foods not be introduced to infants aged 4 months or younger, almost half of the infants in this study had consumed solid foods by the age of 4 months. This early introduction of complementary foods was associated with unhealthful subsequent feeding behaviors.

Effect of Maternity Care Practices on Breastfeeding. 2008. DiGirolamo, Ann M., Laurence M. Grummer-Strawn, Sara B. Fein. Pediatrics 122(suppl 2): S43-S49.
OBJECTIVE: Our goal was to assess the impact of “Baby-Friendly” hospital practices and other maternity-care practices experienced by mothers on breastfeeding duration.
METHODS: This analysis of the Infant Feeding Practices Study II focused on mothers who initiated breastfeeding and intended prenatally to breastfeed for >2 months, with complete data on all variables (n = 1907). Predictor variables included indicators of 6 “Baby-Friendly” practices (breastfeeding initiation within 1 hour of birth, giving only breast milk, rooming in, breastfeeding on demand, no pacifiers, fostering breastfeeding support groups) along with several other maternity-care practices. The main outcome measure was breastfeeding termination before 6 weeks.
RESULTS: Only 8.1% of the mothers experienced all 6 “Baby-Friendly” practices. The practices most consistently associated with breastfeeding beyond 6 weeks were initiation within 1 hour of birth, giving only breast milk, and not using pacifiers. Bringing the infant to the room for feeding at night if not rooming in and not giving pain medications to the mother during delivery were also protective against early breastfeeding termination. Compared with the mothers who experienced all 6 “Baby-Friendly” practices, mothers who experienced none were ~13 times more likely to stop breastfeeding early. Additional practices decreased the risk for early termination.
CONCLUSIONS: Increased “Baby-Friendly” hospital practices, along with several other maternity-care practices, improve the chances of breastfeeding beyond 6 weeks. The need to work with hospitals to implement these practices continues to exist, as illustrated by the small proportion of mothers who reported experiencing all 6 of the “Baby-Friendly” hospital practices measured in this study.

Characteristics of Breastfeeding Practices among U.S. Mothers. 2008. Shealy, Katherine R., Kelley S. Scanlon, Judith Labiner-Wolfe, Sara B. Fein, Laurence M. Grummer-Strawn. Pediatrics 122(suppl 2): S50-S55.
OBJECTIVES: Although much has been published about breastfeeding rates, little is known about how breastfeeding is practiced in the United States. We describe the distributions and characteristics of practices related to common advice about breastfeeding during the infant’s first year of life.
PARTICIPANTS AND METHODS: Participants in the 2005–2007 Infant Feeding Practices Study
II received monthly questionnaires during their infants’ first year of life. Among breastfeeding respondents, we investigated patterns and trends in types of breastfeeding (supplementing with formula or not, and at the breast or not) and maternal report of infant feeding behaviors corresponding to common breastfeeding advice on frequency, duration, and intervals of feedings.
RESULTS: More than half of the breastfeeding mothers fed their infants nothing other than breast milk until 4 months of age. Formula supplementation declined from 42% at 1 month to 15% at 1 year; adding other foods/liquids increasingly surpassed supplementing with formula beginning at 5 months of age. Six percent of the mothers reported that the only breast milk the infant was fed was expressed, rather
than at the breast. Frequency of breast milk feedings per day declined from 8 at 1 month to 3.5 at 1 year. Reported feeding durations of <20 minutes increased from 46% at 1 month to 88% at 1 year. Feeding from both breasts per feeding decreased 15% over the infant’s first year (from 69% to 59%). Longest interfeeding intervals more than doubled over the year.
CONCLUSIONS: Exclusive breastfeeding was common up to 4 but not to 6 months of age.
Breastfeeding with only expressed milk was rare. Considerable variation existed in maternal report of practices that correspond to common breastfeeding advice. More research is needed to better understand how these variations relate to breastfeeding outcomes and the role of common breastfeeding advice in infant feeding decisions.

Success of Strategies for Combining Employment and Breastfeeding. 2008. Fein, Sara B., Bidisha Mandal, Brian E. Roe. Pediatrics 122(suppl 2): S56-S62.
OBJECTIVE: Return to work is associated with diminished breastfeeding intensity and duration. Although more mothers breastfeed after returning to work now than earlier, research has not documented the strategies that mothers use for combining paid work and breastfeeding or their effect on breastfeeding outcomes. This study examined which strategies are associated with smaller decrements in breastfeeding intensity and longer durations.
PARTICIPANTS AND METHODS: We analyzed 810 mothers from the Infant Feeding Practices Study II who worked and breastfed. We used regression and censored regression models to analyze 4 strategies that mothers used to combine these 2 activities: (1) feed directly from the breast only; (2) both pump and feed directly; (3) pump only; and (4) neither pump nor breastfeed during the work day. Outcomes were the difference in percentage of milk feeds that were breast milk between the month before and after return to work and duration of breastfeeding after return to work.
RESULTS: Forty-three percent of mothers pumped milk at work only; 32% fed the infant directly from the breast only. These 2 strategies, along with pumping and feeding directly, were statistically similar and superior to neither pumping nor breastfeeding during the work day for the outcome of change in breastfeeding intensity. For the outcome of breastfeeding duration, the 2 strategies that included
directly feeding from the breast were associated with longer duration than pumping only, whereas the strategy of neither pumping nor breastfeeding during the work day was associated with the shortest duration.
CONCLUSIONS: Feeding the infant from the breast during the work day is the most effective strategy for combining breastfeeding and work. Ways to enable direct feeding include on-site child care, telecommuting, keeping the infant at work, allowing the mother to leave work to go to the infant, and having the infant brought to the work site. Establishing ways for mothers to feed from the breast after return to work is important to meet US breastfeeding goals.

The Prevalence of Breast Milk Expression and Associated Factors. 2008. Labiner-Wolfe, Judith, Sara B. Fein, Katherine Shealy, Cunlin Wang. Pediatrics 122(suppl 2): S63-S68.
OBJECTIVES: Our goal was to describe the prevalence of any, occasional, and regular breast milk expression, mothers' reasons for expressing their milk, and sociodemographic factors associated with breast milk expression.
PARTICIPANTS AND METHODS: Breastfeeding mothers participating in the 2005–2007 Infant Feeding Practices Study II formed the cohort for these analyses, which were conducted among those with infants in 3 age groups: 1.5 to 4.5 months (n = 1564); >4.5 to 6.5 months (n = 1128); and >6.5 to 9.5 months (n = 914). For the analyses we used frequency and stepwise multiple logistic regression procedures.
RESULTS: Eighty-five percent of breastfeeding mothers of infants in the youngest age group had successfully expressed milk at some time since their infant was born. When asked only about the previous 2-week period, 68% of the breastfeeding mothers of infants in this youngest age group had expressed milk, with 43% having done so occasionally and 25% on a regular schedule. Approximately one quarter of breastfeeding mothers of infants in the 2 older infant age groups also expressed milk on a regular schedule. The percentage of mothers expressing milk decreased with increasing infant age. Mothers expressed milk for various reasons. The most frequently cited reason was to get breast milk for someone else to feed their infant. In all 3 age groups, reporting any breast milk expression, compared with none, was positively associated with maternal employment, higher income, lack of previous breastfeeding experience, and living in the Midwest versus the West. In all 3 age groups, expressing milk on a regular schedule, compared with occasionally, was positively associated with maternal employment and the use of an electric versus manual breast pump.
CONCLUSIONS: Breast milk expression is a very common practice. It is associated most strongly with maternal employment, a recognized barrier to breastfeeding.

Why Mothers Stop Breastfeeding: Mothers' Self-reported Reasons for Stopping during the First Year. 2008. Li, Ruowei, Sara B. Fein, Jian Chen, Laurence M. Grummer-Strawn. Pediatrics 122(suppl 2): S69-S76.
OBJECTIVES: Our goal was to determine why women stop breastfeeding at various times during their infant's first year.
METHODS: We analyzed self-reported data from 1323 mothers who participated in the Infant Feeding Practice Study II. Mail questionnaires were sent to mothers ∼2, 3, 4, 5, 6, 7, 9, 10½, and 12 months after their child's birth, in which they were asked to rate the importance of 32 reasons for their decision to stop breastfeeding. We applied exploratory factorial analysis to extract meaningful constructs of mothers' responses to the 32 reasons. We then compared the percentages of mothers who indicated that each reason was important in their decision to stop breastfeeding among various weaning ages and used multiple logistic regression models to examine sociodemographic differences in the most frequently cited reasons for stopping breastfeeding.
RESULTS: The perception that their infant was not satisfied by breast milk alone was cited consistently as 1 of the top 3 reasons in the mothers' decision to stop breastfeeding regardless of weaning age (43.5%–55.6%) and was even more frequent among Hispanic mothers and mothers with annual household incomes of <350% of the federal poverty level. Mothers' concerns about lactation and nutrition issues were the most frequently cited reasons for stopping breastfeeding during the first 2 months. Starting from the third month, self-weaning reasons were increasingly cited as important, with the statements “My baby began to bite” (31.7%), “My baby lost interest in nursing or began to wean himself or herself” (47.3%), and “Breast milk alone did not satisfy my baby” (43.5%) cited as the top 3 reasons at ≥9 months of age.
CONCLUSIONS: Our findings about the major reasons why mothers stop breastfeeding at various times during their child's first year should be useful to health professionals when attempting to help mothers overcome breastfeeding barriers and to health officials attempting to devise targeted breastfeeding interventions on those issues prominent for each infant age.

Association of Breastfeeding Intensity and Bottle Emptying Behaviors at Early Infancy with Infants' Risk for Excess Weight at Late Infancy. 2008. Li, Ruowei, Sara B. Fein, Laurence M. Grummer-Strawn. Pediatrics 122(suppl 2): S77-S84.
OBJECTIVE: Our goal was to test the hypothesis that infants who were breastfed more intensively during early infancy (≤6 months) will be less likely to have excess weight during late infancy (>6 months) and to examine the independent impact of infant-initiated bottle emptying and mothers' encouragement of bottle emptying on infants' risk for excess weight.
METHOD: The sample consisted of 1896 mothers who participated in postpartum surveys of the Infant Feeding Practice Study II and who provided at least 1 weight measurement of their infants during the second half of infancy. We used multiple logistic regression models to assess the association between infants' risks for excess weight during the second half of infancy and 3 self-reported feeding practices during the first half of infancy after adjusting for a series of sociodemographic characteristics. The early feeding practices examined included the percentage of all milk feedings in which infants consumed breast milk (breastfeeding intensity), the frequency of bottle feedings in which infants initiated bottle emptying, and the frequency of bottle feedings in which mothers encouraged bottle emptying.
RESULTS: Infants fed with low (<20% of milk feeds being breast milk) and medium (20%–80%) breastfeeding intensity in the first half of infancy were at least 2 times more likely to have excess weight during the second half of infancy than those breastfed at high intensity (>80%). Infants who often emptied bottles in early infancy were 69% more likely than those who rarely emptied bottles to have excess weight during late infancy. However, mothers' encouragement of bottle emptying was negatively associated with their infants' risk for excess weight during the second half of infancy.
CONCLUSIONS: Infants’ risk for excess weight during late infancy was negatively associated with breastfeeding intensity but positively associated with infant-initiated bottle emptying during early infancy. These findings not only provide evidence for the potential risk of not breastfeeding or breastfeeding at a low intensity in development of childhood obesity, but they also suggest that infant-initiated bottle emptying may be an independent risk factor as well.

Infant Formula Handling Education and Safety. 2008. Labiner-Wolfe, Judith, Sara B. Fein, Katherine Shealy. Pediatrics 122(suppl 2): S85-S90.
OBJECTIVES: Our goal was to assess the extent to which mothers learn about proper handling of infant formula from health professionals and package labels; mothers' beliefs about the likelihood of germs being in infant formula and the importance of following safe-use directions; whether they take measures while handling infant formula to prevent foodborne illnesses and injury to their infants; and maternal characteristics associated with unsafe infant formula–handling practices.
PARTICIPANTS AND METHODS: The study cohort consisted of mothers participating in the 2005–2007 Infant Feeding Practices Study II who fed their infant formula. We conducted frequency and multiple logistic regression analyses. Sample sizes for the analyses ranged from 860 to 1533.
RESULTS: The majority of formula-feeding mothers did not receive instruction on formula preparation (77%) or storage (73%) from a health professional. Thirty percent did not read some of the safe-use directions on the formula package label; an approximately equal percentage (38%) thought that both powdered (which is not sterile) and ready-to-feed (which is sterile) formula were unlikely to contain germs; and 85% believed that following safe-storage directions was very important. Among the mothers of the youngest infants analyzed, 55% did not always wash their hands with soap before preparing infant formula, 32% did not adequately wash bottle nipples between uses, 35% heated formula bottles in a microwave oven, and 6% did not always discard formula left standing for >2 hours. The prevalence of these unsafe practices was similar among mothers of older infants. No consistent pattern of maternal characteristics was associated with unsafe practices.
CONCLUSIONS: Many mothers do not follow safe practices when preparing infant formula. Additional research is needed to understand why more mothers do not follow safe formula-handling recommendations.

Selected Complementary Feeding Practices and their Association with Maternal Education. 2008. Fein, Sara B., Judith Labiner-Wolfe, Kelley S. Scanlon, Laurence M. Grummer-Strawn. Pediatrics 122(suppl 2): S91-S97.
OBJECTIVE: As infants transition from a milk-based diet to one that includes most food groups, the timing of the transition, how infants are fed, and the quality of their diet can have important health implications. Our objective is to describe these factors for US infants.
METHODS: We analyzed data from the Infant Feeding Practices Study II. Sample sizes varied for relevant questions from ∼1600 to ∼2400. We analyzed the prevalence of 14 feeding practices and their association with the mothers' education and also examined participants' use of commercial baby foods.
RESULTS: Approximately 21% of the mothers introduced solid foods before 4 months; 7% introduced solids after 6 months. Twenty-nine percent of the mothers introduced >3 new foods per week to infants aged 5 to 10 months. Approximately 20% of the mothers fed juice before 6 months, fed cow's milk before 12 months, and fed infants <5 times per day after 5 months. Fourteen percent of the mothers chewed food for their infant. Approximately 15% of the mothers fed <1 serving daily of either a fruit or vegetable to infants aged ≥9 months, half added salt to their infant's food, and more than one third who added salt used noniodized salt. Approximately 20% fed reduced-fat cow's milk at 1 year. Almost half of the 10-month-old infants had eaten restaurant food in a restaurant in the previous week, 22% had eaten carry-out food, and 28% had eaten either type of restaurant food ≥2 times. The prevalence of 8 of the 14 unhealthful infant feeding practices we examined was inversely associated with maternal education.
CONCLUSIONS: Nutrition and feeding guidance should be especially targeted to mothers with a high school education or less.

Sources of Supplemental Iron Among Breastfed Infants During the First Year of Life. 2008. Dee, Deborah L., Andrea J. Sharma, Mary E. Cogswell, Laurence M. Grummer-Strawn, Sara B. Fein, Kelley S. Scanlon. Pediatrics 122(suppl 2): S98-S104.
OBJECTIVES: Primary prevention of iron deficiency requires adequate iron intake. Although recommendations exist to promote adequate intake of iron among infants through iron-rich foods and iron supplements, few studies have examined adherence to these recommendations. Our objectives were to describe the consumption of iron-rich foods, oral iron supplements, and iron-fortified formula among US infants and to assess adherence to iron-intake recommendations.
METHODS: We analyzed data from the Infant Feeding Practices Study II, a longitudinal study of mothers and infants followed from late pregnancy through the first year of their infant’s life. Mothers completed near-monthly questionnaires that assessed how frequently they fed their infants breast milk, formula, infant cereals, and meats in the previous 7 days and whether their infants were given an oral iron supplement ≥3 times per week during the previous 2 weeks. We examined use of iron-fortified formula among infants who consumed formula; intake of cereal, meat, oral iron
supplements, and formula among infants consuming any breast milk; and whether 6-month-old breastfed and mixed-fed (breast milk and formula) infants consumed sources of supplemental iron with recommended frequency.
RESULTS: At 6 months of age, 18% of the term breastfed and mixed-fed infants had not received infant cereal or meat in the previous 7 days, and 15% had not received infant cereal, meat, regular iron supplements, or formula; among solely breastfed infants, 23% had not received infant cereal, meat, or regular iron supplements. Fifty-eight percent of the mixed-fed infants and 70% of the solely breastfed infants received <2 daily servings of infant cereal, meat, or formula combined and did not receive oral iron supplements ≥3 times per week. Among preterm breastfed and mixed-fed infants, none received oral iron supplements ≥3 times per week before 3 months of age, 2% received them at 3 months, and 13% received them at 10.5 months.
CONCLUSIONS: Our findings indicate that recommendations regarding iron intake among breastfed infants are not being followed by a substantial proportion of mothers.

Maternally-reported Food Allergies and Other Food-related Health Problems in Infants: Characteristics and Associated Factors. 2008. Luccioli, Stefano, Marianne Ross, Judith Labiner-Wolfe, Sara B. Fein. Pediatrics 122(suppl 2): S105-S112.
OBJECTIVE: Our goal was to identify the frequency, demographics, and diagnostic characteristics associated with maternally reported food allergies and other food-related health problems among infants aged ≤1 year.
METHODS: We analyzed data from the 2005–2007 Infant Feeding Practices Study II, a longitudinal survey of 2441 US mothers of healthy singletons from pregnancy through their infant's first year. Doctor diagnosis and symptoms-based criteria were used to identify a probable-food-allergic group from maternal reports of infant health problems with food.
RESULTS: More than one fifth of the 2441 mothers reported that their infant had a food-related problem; 6% (n = 143) had a probable food allergy, and 15% (n = 359) had other food-related problems. Forty percent of the infants with a food-related health problem were evaluated by a doctor. Gastrointestinal symptoms were more commonly reported in early infancy compared with skin-related symptoms, which were reported in later infancy, and 27% received medical treatment for the symptoms. Characteristics associated with increased incidence of probable food allergy included family histories of food allergy and type 1 diabetes, gestational diabetes, living in rural or urban areas, being black, and being male. Among all infants with a food-related health problem, the majority experienced their first problem by 6 months of age. Foods recognized to be major allergens were most commonly reported as the source of an allergy.
CONCLUSIONS: Food-related problems occurred at a high frequency in the first year of life. A better understanding of the demographics, family history, disease manifestations, and diagnoses may provide insight into public health efforts to minimize or prevent food allergies in infancy and to help differentiate food-allergic problems from nonallergic food problems in this age group.

Infant Sleeping Arrangements and Practices during the First Year of Life. 2008. Hauck, Fern R, Caroline Signore, Sara B. Fein, Tonse N. K. Raju. Pediatrics 122(suppl 2): S113-S120.
OBJECTIVES: Our goal was to examine the sleeping arrangements for infants from birth to 1 year of age and to assess the association between such arrangements and maternal characteristics.
METHODS: Responses to the 3-, 6-, 9-, and 12-month questionnaires from the Infant Feeding Practices Study II were analyzed to assess sleep arrangements, including bed sharing, the latter defined as mother ever (in a given time frame) slept with the infant on the same sleeping surface for nighttime sleep. Women were also asked about the reasons for bed sharing or not bed sharing.
RESULTS: Approximately 2300 women responded at 3 months, and 1800 at 12 months. At 3 months, 85% of the infants slept in the same room as their mother, and at 12 months that rate was 29%. At 3 months, 26% of the mothers did not use the recommended supine position for their infant's nighttime sleep. The rate of noncompliance increased to 29% by 6 months and 36% by 12 months. The bed-sharing rates were 42% at 2 weeks, 34% at 3 months, and 27% at 12 months. Approximately two thirds of those who bed shared with their infant also shared the bed with their husband or partner, and 5% to 15% shared it with other children. The major reasons for bed sharing were to calm a fussy infant, facilitate breastfeeding, and help the infant and/or mother sleep better. The major reasons for not lying down with the infant were safety concerns. Non-Hispanic black mothers were more likely than non-Hispanic white mothers to use nonsupine infant sleep positions and to bed share.
CONCLUSIONS: More than one third of the women in this cohort were noncompliant with safe-sleeping guidelines when their infant was 3 months old. Health care providers need to advise parents of current recommendations and discuss the risks and benefits of their choices for infant sleeping practices.

The differential effects of full-time and part-time work status on breastfeeding. 2010. Mandal, Bidisha, Brian E. Roe, and Sara Beck Fein. Health Policy 97:79-86.
OBJECTIVES: Return to work is associated with diminished breastfeeding. Although more mothers breastfeed after returning to work compared to a decade ago, research has not documented the variations in breastfeeding initiation and duration based on full-time and part-time (less than 35 h/week) work status. In this study, we clarify these differences.
METHODS: Longitudinal data from the Infant Feeding Practices Study II, collected between 2005 and 2007, for over 1400 mothers are used. In analyzing initiation, mother's work status was categorized by the expected number of hours she planned to work postpartum. In the duration model, work status was categorized based on the actual number of hours worked upon mother's return to employment after controlling for baby's age when she returned to work. Covariates in logistic and censored regressions included demographics, maternity leave, parity, past breastfeeding experience, hospital experience, and social support.
RESULTS: Compared with expecting not to work, expecting to work <35 h/week was not associated with breastfeeding initiation while expecting to work full-time decreased breastfeeding initiation. Compared with breastfeeding mothers who did not work, returning to work within 12 weeks regardless of work status and returning to work after 12 weeks while working more than 34 h/week were associated with significantly shorter breastfeeding duration.
CONCLUSION: Part-time work and increased amount of leave taken promote breastfeeding initiation and duration.

Do infants fed from a bottle lack self-regulation of milk intake compared with infants fed directly from the breast? 2010. Li, Ruowei, Sara B. Fein, Laurence M. Grummer-Strawn. Pediatrics 125:e1386-e1393.
OBJECTIVE: How breastfeeding reduces the risk of childhood obesity is unclear, and 1 hypothesis pertains to the ability of breastfed infants to self-regulate. We studied whether infants' self-regulation of milk intake is affected by feeding mode (bottle versus breast) and the type of milk in the bottle (formula versus expressed breast milk).
PATIENTS AND METHODS: Participants in the 2005–2007 Infant Feeding Practices Study II received monthly questionnaires during their infant's first year, and complete data were available for 1250 infants. We tested the impact of feeding mode and type of milk during early infancy on self-regulation during late infancy.
RESULTS: Although only 27% of infants fed exclusively at the breast in early infancy emptied the bottle or cup in late infancy, 54% of infants who were fed both at the breast and by bottle did so, and 68% of those who were fed only by bottle did so. Multivariate regression analysis indicated that infants who were bottle-fed more intensively early in life were ∼71% or 2 times more likely to empty the bottle or cup later in life than those who were bottle-fed less intensively (⅓–⅔ or ⅔ of milk feeds given by bottle versus < ⅓ of milk feeds). When feeding formula and expressed milk were considered separately, similar dose-response relationships were observed.
CONCLUSIONS: Infants who are bottle-fed in early infancy are more likely to empty the bottle or cup in late infancy than those who are fed directly at the breast. Bottle-feeding, regardless of the type of milk, is distinct from feeding at the breast in its effect on infants' self-regulation of milk intake.

Associations between high prepregnancy body mass index, breast-milk expression, and breast-milk production and feeding. 2011. Leonard, Stephanie A., Judith Labiner-Wolfe, Sheela R Geraghty, Kathleen M. Rasmussen. The American Journal of Clinical Nutrition 93:556-563.
BACKGROUND: Breast-milk expression is widely practiced by American mothers, but little is known about who expresses milk, how expression affects breastfeeding, or whether overweight or obese women, who have less breastfeeding success than do normal-weight women, express milk differently.
OBJECTIVES: We investigated 1) whether breast-milk expression behavior differed by body mass index (BMI; in kg/m2) category and 2) whether the different breastfeeding behaviors of overweight (BMI: ≥25 and <30) and obese (BMI: ≥30) women resulted in different breastfeeding outcomes.
DESIGN: The subjects (n = 2288) provided information on BMI and breast-milk production, feeding, and expression in mail-in questionnaires as part of the Infant Feeding Practices Study II. Longitudinal and cross-sectional data were analyzed by using regression procedures adjusted for confounding.
RESULTS: Women of different BMI categories overall did not differ in whether, when, or why they expressed breast milk. Before 2 mo postpartum, however, obese women were more likely (P = 0.04, unadjusted) to try milk expression and were less likely (P = 0.01, unadjusted) to express milk successfully. In addition, overweight or obesity was associated (P < 0.03, unadjusted) with a shorter duration of breast-milk production only in women who never expressed milk. In overweight or obese women, those who ever expressed milk had longer durations of breastfeeding (P < 0.003, unadjusted) than did those who never expressed milk.
CONCLUSIONS: Breast-milk expression behaviors may differ by maternal BMI category only in the early postpartum period. In addition, breast-milk expression may reduce differences between BMI categories in the duration of breastfeeding and support longer durations of breastfeeding.

Feeding of Dietary Botanical Supplements and Teas to Infants in the United States. 2011. Zhang, Yuanting, Elizabeth B. Fein, Sara B. Fein. Pediatrics 127:1060–1066.
OBJECTIVES: To describe the use of dietary botanical supplements and teas among infants, the characteristics of mothers who give them the specific botanical supplements and teas used, reasons for use, and sources of information.
METHODS: We used data from the Infant Feeding Practices Study II, a longitudinal survey of women studied from late pregnancy through their infant's first year of life conducted by the US Food and Drug Administration and the Centers for Disease Control and Prevention between 2005 and 2007. The sample was drawn from a nationally distributed consumer opinion panel and was limited to healthy mothers with healthy term or near-term singleton infants. The final analytical sample included 2653 mothers. Statistical techniques include frequencies, χ2 tests, and ordered logit models.
RESULTS: Nine percent of infants were given dietary botanical supplements or teas in their first year of life, including infants as young as 1 month. Maternal herbal use (P < .0001), longer breastfeeding (P < .0001), and being Hispanic (P = .016) were significantly associated with giving infants dietary botanical supplements or teas in the multivariate model. Many supplements and teas used were marketed and sold specifically for infants. Commonly mentioned information sources included friends or family, health professionals, and the media.
CONCLUSIONS: A substantial proportion of infants in this sample was given a wide variety of supplements and teas. Because some supplements given to infants may pose health risks, health care providers need to recognize that infants under their care may be receiving supplements or teas.

Risk of Bottle Feeding for Rapid Weight Gain During the First Year of Life. 2012. Li, Ruowei, Joselito Magadia, Sara B. Fein, Laurence M. Grummer-Strawn. Archives of Pediatrics and Adolescent Medicine 166(5):431-436.
OBJECTIVES: To better understand the mechanisms behind breastfeeding and childhood obesity, we assessed the association of weight gain with the mode of milk delivery aside from the type of milk given to infants.
DESIGN: A longitudinal study of infants followed up from birth to age 1 year. Multilevel analyses were conducted to estimate infant weight gain by type of milk and feeding mode.
SETTING: Pregnant women were recruited from a consumer mail panel throughout the United States between May 2005 and June 2007.
PARTICIPANTS: One thousand eight hundred ninety nine infants with at least 3 weight measurements reported during the first year.
MAIN EXPOSURES: Six mutually exclusive feeding categories and proportions of milk feedings given as breastmilk or by bottle.
MAIN OUTCOME MEASURES: Weight measurements reported on 3-, 5-, 7-, and 12-month surveys.
RESULTS: Compared with infants fed at the breast, infants fed only by bottle gained 71 or 89 g more per month when fed nonhuman milk only (P < .001) or human milk only (P = .02), respectively. Weight gain was negatively associated with proportion of breastmilk feedings, but it was positively associated with proportion of bottle-feedings among those who received mostly breastmilk. Among infants fed only breastmilk, monthly weight gain increased from 729 g when few feedings were by bottle to 780 g when most feedings were by bottle.
CONCLUSIONS: Infant weight gain might be associated not only with type of milk consumed but also with mode of milk delivery. Regardless of milk type in the bottle, bottle-feeding might be distinct from feeding at the breast in its effect on infants' weight gain.

Awareness of Methylmercury in Fish and Fish Consumption among Pregnant and Postpartum Women and Women of Childbearing Age in the United States. 2012. Lando, Amy M., Sara B. Fein, and Conrad J. Choinière. Environmental Research 116: 85-92.
In 2004, the Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA) reissued joint advice recommending that pregnant women, nursing mothers, young children, and women who may become pregnant not consume fish high in mercury such as shark, swordfish, king mackerel, and tilefish, and not consume more than 12 ounces (340.2 g) of other lower mercury fish per week. These groups were encouraged to eat up to 12 ounces (340.2 g) of low mercury fish per week to get the health benefits of fish. Using a survey of 1286 pregnant women, 522 postpartum women, and a control group of 1349 non-pregnant/non-postpartum women of childbearing age, this study evaluated awareness of mercury as a problem in food and examined fish consumption levels across groups using regression analysis. We also compared awareness of mercury as a problem in food to awareness of Listeria, dioxins and PCBs. We found that the majority of all 3 groups of women were aware of mercury and that nearly all women in all 3 groups limited consumption consistent with the advice; they ate less than 340.2 g (12 oz) of fish per week and no high mercury fish. Compared with the control group, pregnant and postpartum women were more likely to be aware of mercury as a problem in food, and pregnant women ate less total fish and were less likely to eat fish, to eat more than 340.2 g (12 oz) of fish, and to eat high mercury fish. However, all groups ate much less than the recommended 340.2 g (12 oz) of low mercury fish per week for optimum health benefits. Among women who ate fish, the median intake of total fish was 51.6 g/wk (1.8 oz/wk), 71.4 g/wk (2.5 oz/wk), and 85.3 g/wk (3.0 oz/wk) for the pregnant, postpartum, and control groups, respectively. Thus, it appears that the targeted groups of women were more aware of mercury and were eating fish within the FDA/EPA guidelines, but these women may be missing the health benefits to themselves and their children of eating a sufficient amount of fish.

How US mothers store and handle their expressed breast milk. 2013. Labiner-Wolfe, Judith, and Sara B. Fein. Journal of Human Lactation 29(1): 54-58.
BACKGROUND: Many mothers express and store their milk to later feed to their infant. Health organizations provide recommendations on expressed milk storage and handling because these practices can affect milk quality and safety. However, little information exists on US mothers’ practices.
OBJECTIVE: To describe how US mothers of healthy infants store and handle their expressed milk and to compare their practices with recommendations.
METHODS: Mothers participating in the Infant Feeding Practices Study II from 2005-2006 who were expressing milk formed the cohort for this analysis (n = 436-1060, depending on infant age). Participants in this longitudinal mail survey were drawn from a consumer opinion panel and answered questions about milk expression around 2, 5, and 7 months postpartum. Data were analyzed cross sectionally using frequency procedures, and the analysis compared mothers who fed expressed milk with and without also feeding formula.
RESULTS: Few mothers stored their milk longer than recommended. Among mothers of the youngest infants in this analysis, 12% heated their milk in a microwave and 17% rinsed bottle nipples with only water before reuse; percentages were similar as infants aged. These practices may pose risks to infant health. Compared with those who fed no formula, mothers who fed both expressed milk and formula were more likely to heat milk in a microwave and, among those with the youngest infants, to rinse bottle nipples with only water between uses.
CONCLUSION: Consumer education should emphasize safe warming and cleaning practices for feeding expressed milk.

Work and breastfeeding decisions are jointly determined for higher socioeconomic status US mothers. 2014. Mandal, Bidisha, Brian E. Roe, and Sara B. Fein. Review of Economics of the Household 12(2): 237-257.
We study postpartum decisions about paid work and breastfeeding using a simultaneous equations model. For our sample of higher socioeconomic status mothers, we find a joint decision process for three sets of decisions modeled: work leave duration and duration of any, as well as of exclusive, breastfeeding, and daily work hours and daily breastfeedings at infant age 3 months. We find that returning to paid work 1 week earlier reduces any breastfeeding duration by about two-thirds of a week while extending breastfeeding by a week delays work participation by about one-third of a week. We find larger elasticities for decisions involving daily work hours and number of breastfeedings at 3 months than for work leave duration and any breastfeeding duration and the smallest elasticities for duration of exclusive breastfeeding and work leave. This marks the first study to find a joint decision-making process for postpartum work and breastfeeding decisions and suggests that, in addition to increased leave impacting breastfeeding behaviors, successful breastfeeding promotion policies can have nontrivial impacts on the US labor market.

Association of Health Profession and Direct‐to‐Consumer Marketing with Infant Formula Choice and Switching. 2013. Huang, Yi, Judith Labiner‐Wolfe, Hui Huang, Conrad J Choiniere, and Sara B. Fein. Birth 40 (1): 24-31.
BACKGROUND: Infant formula is marketed by health professionals and directly to consumers. Formula marketing has been shown to reduce breastfeeding, but the relation with switching formulas has not been studied. Willingness to switch formula can enable families to spend less on formula.
METHODS: Data are from the Infant Feeding Practices Study II, a United States national longitudinal study. Mothers were asked about media exposure to formula information during pregnancy, receiving formula samples or coupons at hospital discharge, reasons for their formula choice at infant age 1 month, and formula switching at infant ages 2, 5, 7, and 9 months. Analysis included 1,700 mothers who fed formula at infant age 1 month; it used logistic regression and longitudinal data analysis methods to evaluate the association between marketing and formula choice and switching.
RESULTS: Most mothers were exposed to both types of formula marketing. Mothers who received a sample of formula from the hospital at birth were more likely to use the hospital formula 1 month later. Mothers who chose formula at 1 month because their doctor recommended it were less likely to switch formula than those who chose in response to direct-to-consumer marketing. Mothers who chose a formula because it was used in the hospital were less likely to switch if they had not been exposed to Internet web-based formula information when pregnant or if they received a formula sample in the mail. CONCLUSIONS: Marketing formula through health professionals may decrease mothers' willingness to switch formula.

The Association of Prenatal Media Marketing Exposure Recall with Breastfeeding Intentions, Initiation and Duration. 2013. Zhang, Yuanting, Ewa Carlton, Sara B. Fein. Journal of Human Lactation 29(4) 500–509.
BACKGROUND: Infant formula marketing, either directly to consumers or through health care providers, may influence women’s breastfeeding intentions, initiation, and duration. However, little is known about the impact of different types of media marketing on infant feeding intentions and behavior.
OBJECTIVE: This study investigated whether different types of recalled prenatal media marketing exposure to formula and breastfeeding information are related to breastfeeding intentions and behavior.
METHODS: Data were from the Infant Feeding Practices Study II, a longitudinal study from pregnancy through the infants’ first year. Sample sizes ranged from 1384 to 2530. Negative binomial, logistic regression, and survival models were used to examine associations between recalled prenatal exposure to formula or breastfeeding information and breastfeeding intentions and behavior.
RESULTS: Exposure to infant formula information from print media was associated with shorter intended duration of exclusive breastfeeding, and formula information from websites was related to lower odds of both intended and actual initiation. Exposure to breastfeeding information from websites was related to higher odds of both intended and actual initiation and longer intended duration of any breastfeeding. Breastfeeding information from print media was associated with longer duration of any breastfeeding, but information from broadcast media was associated with shorter duration of any breastfeeding.
CONCLUSION: Mothers who recall exposure to formula information from print or websites are more likely to intend to use formula or to intend to use formula earlier and are less likely to initiate breastfeeding than mothers who do not recall seeing such information.

Influence of bedsharing activity on breastfeeding duration among US mothers. 2013. Huang, Yi, Fern R. Hauck, Caroline Signore, Airong Yu, Tonse NK Raju, Terry T-K. Huang, and Sara B. Fein. JAMA pediatrics 167 (11): 1038-1044.
IMPORTANCE: Some professional associations advocate bedsharing to facilitate breastfeeding, while others recommend against it to reduce the risk of sudden infant death syndrome and suffocation deaths. A better understanding of the quantitative influence of bedsharing on breastfeeding duration is needed to guide policy.
OBJECTIVE: To quantify the influence of bedsharing on breastfeeding duration.
DESIGN, SETTING, AND PARTICIPANTS: Longitudinal data were from the Infant Feeding Practices Study II, which enrolled mothers while pregnant and followed them through the first year of infant life. Questionnaires were sent at infant ages 1 to 7, 9, 10, and 12 months, and 1846 mothers answered at least 1 question regarding bedsharing and were breastfeeding at infant age 2 weeks.
Exposures: Bedsharing, defined as the mother lying down and sleeping with her infant on the same bed or other sleeping surfaces for nighttime sleep or during the major sleep period.
MAIN OUTCOMES AND MEASURES: Survival analysis to investigate the effect of bedsharing on duration of any and exclusive breastfeeding.
RESULTS: Longer duration of bedsharing, indicated by a larger cumulative bedsharing score, was associated with a longer duration of any breastfeeding but not exclusive breastfeeding, after adjusting for covariates. Breastfeeding duration was longer among women who were better educated, were white, had previously breastfed, had planned to breastfeed, and had not returned to work in the first year postpartum.
CONCLUSIONS AND RELEVANCE: Multiple factors were associated with breastfeeding, including bedsharing. Given the risk of sudden infant death syndrome related to bedsharing, multipronged strategies to promote breastfeeding should be developed and tested.

Maternal and Breast Pump Factors Associated with Breast Pump Problems and Injuries. 2014. Qi, Youlin, Yuanting Zhang, Sara Fein, Cunlin Wang, and Nilsa Loyo-Berríos. Journal of Human Lactation 30 (1) 110-112.
BACKGROUND: Benefits of using a breast pump are well documented, but pump-related problems and injuries and the associated risk factors have not been reported.
OBJECTIVES: This study aimed to describe breast pump-related problems and injuries and identify factors associated with these problems and injuries.
METHODS: Data were from the Infant Feeding Practices Study II; mothers were recruited from a nationally distributed consumer opinion panel. Mothers were asked about breast pump use, problems, and injuries at infant ages 2, 5, and 7 months. Survival analysis was used to identify factors associated with pump-related problems and injuries.
RESULTS: The sample included 1844 mothers. About 62% and 15% of mothers reported pump-related problems and injuries, respectively. The most commonly reported problem was that the pump did not extract enough milk and the most commonly reported injury was sore nipples. Using a battery-operated pump and intending to breastfeed less than 12 months were associated with higher risks of pump-related problems and injury. Learning from a friend to use the pump was associated with lower risk of pump-related problems, and using a manual pump and renting a pump were associated with a higher risk of problems.
CONCLUSION: Our results suggest that problems and injuries associated with breast pump use can happen to mothers of all socioeconomic characteristics. Breastfeeding mothers may reduce their risks of problems and injury by not using battery-operated pumps and may reduce breast pump problems by not using manual pumps and by learning breast pump skills from a person rather than following written or video instructions.

Infant Feeding Practices and Reported Food Allergies at 6 Years of Age. 2014. Luccioli, Stefano, Yuanting Zhang, Linda Verrill, Moraima Ramos-Valle, and Ernest Kwegyir-Afful. Pediatrics 134: S21-S28.
The goal of this study was to identify the frequency of physician-diagnosed food allergies among 6-year-old US children and study the impact of exclusive breastfeeding and complementary food introduction on this frequency. Data were analyzed from children who participated in the Infant Feeding Practices Study II Year 6 Follow-Up Study (Y6FU). Children with probable food allergy (pFA) were defined as children with report of physician-diagnosed food allergy at age 6 years. Subgroups of pFA included children who were not diagnosed before 1 year of age (new pFA) and those with atopic risk factors (high risk). Prevalence of total pFA in the Y6FU was 6.34%. The majority of these children had new pFA and high-risk factors. Higher maternal education, higher family income, family history of food allergy, and reported eczema before 1 year of age were significantly associated with higher odds of total or new pFA. Exclusive breastfeeding duration and timing of complementary food introduction were not significantly associated with total pFA. However, exclusive breastfeeding of 4 months compared with no breastfeeding was marginally associated with lower odds of new pFA (adjusted odds ratio: 0.51; P = .07); this effect was not observed with high-risk children. Analysis of infant and maternal variables in the Y6FU cohort of US children revealed that socioeconomic and atopic factors were the main predictors of pFA at age 6 years. Exclusive breastfeeding of 4 months may have a preventive effect on development of pFA after 1 year of age in non high-risk children.


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