![[Feedback]](/icons/banner/feedbackACT.gif){kind=icon}
![[For Subscribers]](/icons/banner/subscriberACT.gif){kind=icon}
![[Archive]](/icons/banner/archiveACT.gif){kind=icon}
![[Search]](/icons/banner/searchACT.gif){kind=icon}
![[Contents]](/icons/banner/tocACT.gif){kind=icon}
|
|
|
|
|
||
Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853
3To whom correspondence should be addressed. E-mail: kmr5{at}cornell.edu.
 |
ABSTRACT |
|---|
 TOP ABSTRACT SUBJECTS AND METHODSRESULTSDISCUSSIONLITERATURE CITED |
|---|
KEY WORDS: • breastfeeding • BMI • ethnic groups • lactation • obesity
Among the Surgeon General’s health goals for 2010 are that 75% of women initiate breastfeeding (BF)4 and that 50% continue BF through 6 mo postpartum (1). These goals were unmet in 2000, but recent data (2) suggest progress toward these goals, particularly among sociodemographic groups that have been historically less likely to breastfeed. Nevertheless, rates of BF remain suboptimal, particularly among women who are non-Caucasian, younger, less educated, or participants in the Supplemental Nutrition Program for Women, Infants and Children (WIC) (2).
The decision to attempt BF is influenced by socioeconomic status, education, race/ethnicity, and social support (3). Once lactation is successfully initiated, many factors influence the continuation of BF. Generally, women who are older; more educated; involved in healthy, stable relationships; and of higher socioeconomic standing continue to breastfeed longer (2,4,5). This picture is more complex among minority women, because additional factors, such as acculturation (6), the belief that the baby prefers formula (7), the woman’s own preference for bottle feeding (8), or the complex interaction of a variety of factors (9) may also influence the initiation and the continuation of BF among those who have ever attempted to nurse their babies.
Results from studies in rats suggest that obesity is a biological factor that negatively affects the establishment of successful lactation (10). The mechanisms by which excess body fat influences the rat’s ability to nurse her litter successfully include an inappropriate metabolic transition from pregnancy to lactation and changes in milk composition and volume that result in impaired pup growth (10). In an Australian study, investigators found that among women who had successfully breastfed for 
2 wk, those who had a BMI > 26 kg/m2 at 1 mo postpartum were 1.5 times more likely to discontinue BF before their infants were 3 mo old than were those who had a lower BMI (11). In a population of Caucasian women, we showed that among women who had attempted to breastfeed their infants, both overweight and obese women were less successful at initiating and continuing to breastfeed than their normal weight counterparts (12). Compared with normal-weight women in this study, the OR for failing to successfully initiate BF was a 2.54 (P < 0.05) for overweight women, and 3.65 (P = 0.0008) for obese women. The overweight and obese women also had higher rates of discontinuation of exclusive BF or any BF. We observed that delayed onset of copious milk secretion (lactogenesis II) is associated with higher maternal prepregnant BMI in Caucasian women (13); others also observed this association in Hispanic women (14). Delayed lactogenesis and premature cessation of BF are related to an inadequate prolactin response to suckling, which we recently documented in Caucasian women at 7 d postpartum (15).
This association has not been studied in detail in racial/ethnic groups other than Caucasian women. Factors associated with the decision to attempt BF, such as education and racial/ethnic group, are also associated with increasing rates of overweight and obesity (16). The prevalence of obesity among women of childbearing age in the United States has increased markedly in past decades. In the 1999–2000 National Health and Nutrition Examination Survey (NHANES), well over half of Black and Mexican American women of reproductive age were overweight or obese (16). Therefore, short durations of BF in Black and Hispanic women could reflect biological factors, sociocultural factors, or both. This study was designed to test the hypothesis that among Black and Hispanic women who attempted to breastfeed their infants in the hospital, those women who were overweight or obese at conception would be less successful at initiation of BF and would breastfeed for shorter periods than normal-weight women, independent of potentially confounding factors.
|
SUBJECTS AND METHODS |
|---|
|
TOPABSTRACTSUBJECTS AND METHODSRESULTSDISCUSSIONLITERATURE CITED |
|---|
The 2 hospitals included in this research were similar in many aspects. Both follow the guidelines of the WHO/United Nations Children’s Fund Baby-Friendly Hospital Initiative for the promotion of BF success, and 1 has received the "baby-friendly" designation (17). Both hospitals have on-site BF counselors, and members of the nursing staff observe and document on a standard form the type and the quality of infant feeding. Both hospitals are accredited teaching sites for physician-residents in training and are affiliated with the same medical school. Both hospitals have adjoining independent pediatric clinics, which infants can attend for well-baby and intercurrent illness care, and both pediatric clinics were included in this research. The larger hospital serves as the tertiary referral center for the region; this site is located closer to the inner city core.
The population of minority women from which we drew our sample included all those of Hispanic ethnicity (Caucasian, Black, or mixed Caucasian and Black race) and all those of Black race (non-Hispanic only, Black, or mixed Caucasian and Black race). To ensure an adequate number of subjects, we included all births to Hispanic women in the years 1998, 1999, and 2000 (3 y), and all the births to Black women during 1999 and 2000 (2 y) at the 2 study hospitals, essentially all births in the city for those minority groups in those years.
The study was limited to healthy mothers between 19 and 40 y old at delivery, with a BMI 19.1 kg/m2, who gave birth to a healthy singleton infant at term. From hospital administrative data, we identified 1581 Black and 1103 Hispanic women who met these criteria (Fig. 1). From information in hospital obstetrical databases and medical records, we identified maternal-infant dyads with circumstances that could make BF more difficult or contraindicated. Those infants who died in infancy, had a hospital stay of 7 d after birth, required ongoing treatment or intervention in the neonatal intensive care unit (NICU) or transfer to the hospital with a level III NICU, had respiratory or other illness that precluded feeding by mouth for 12 h after birth, had a cleft lip or palate or a neural tube defect, or were discharged to foster care or were adopted were not included. Mothers who required hospitalization for 7 d after delivery, had insulin-dependent diabetes mellitus, or had other serious medical or social conditions were not included. There were 1495 Black women and 1032 Hispanic women who met these selection criteria. Cases in which the infant’s medical records were not located after at least 3 attempts or in which the charts lacked sufficient documentation to determine BF behavior in the hospital were excluded (18 Black and 11 Hispanic dyads).
|
Statistical methods
Data were analyzed by using the Statistical Package for Social Sciences (SPSS for Windows, version 10.1; SPSS).
Sample characteristics. Student’s 2-tailed t tests were used to compare the characteristics of women, infants, and obstetrical outcomes at the 2 hospitals, to compare the characteristics of the cases excluded because of inadequate documentation to the remaining dyads available for study, and to compare the characteristics of dyads with and without infant follow-up. Cases from the 2 hospitals were combined to provide an adequate sample of women in each racial/ethnic group. Separate analyses were performed for each racial/ethnic group.
Comparison of women by BMI category. The mother’s BMI was calculated by using height and prepregnancy weight recorded on the New York State prenatal form. This information, recorded by the health care provider when performing the initial obstetrical history and risk assessment, could be self-reported or measured; we could not confirm which method was used for individual cases. For comparability to our prior research (12), women were classified by their BMI value by using guidelines from the Institute of Medicine (18): normal (19.1–26.0 kg/m2), overweight (26.1–29.0 kg/m2), and obese (>29.1 kg/m2). The characteristics of the women and the infants in each category were compared by using ANOVA; Dunnett’s t test procedure was used to compare each BMI category with the normal-weight (reference) group.
Analysis of the initiation of breastfeeding. Multiple multinomial logistic regression was used to evaluate the relation between maternal overweight and obesity in the prepregnant period and the successful initiation of BF at the time of hospital discharge. Successful BF initiation was evaluated by using the last 5 feeds before discharge documented on the mother-infant nutrition flowchart (exclusively breast, combination of formula and breast, or formula only).
All women who met the selection criteria with a value for prepregnant BMI who attempted to breastfeed on at least 1 occasion in the hospital were included (640 Black and 587 Hispanic women). Maternal overweight and obesity were included in the model as main effects with normal BMI as the reference value. The model was adjusted for the following continuous variables: maternal age at delivery, duration of maternal education in years (also a proxy for socioeconomic status), infant birth weight, and length of gestation. Maternal parity was included as a categorical variable: no previous live births (reference group), 1 or 2 previous live births, and 3 or more previous live births. Delivery by cesarean section and smoking at the first prenatal visit were included as dichotomous variables.
Analysis of the duration of breastfeeding.
To assess whether BMI at conception was associated with the duration of BF, the method of infant feeding was obtained from pediatric outpatient records. Duration of any or exclusive BF was noted when available. Otherwise, the type of feeding at well-baby visits (at 
2 wk, and at 2, 4, and 6 mo of age) and intercurrent appointments or telephone calls with documentation of infant feeding were recorded. Infant age on the date of the visit was calculated from the date of birth. The length of exclusive BF (EBF) after discharge was defined as the last time the mother/caregiver reported feeding only breast milk without adding infant formula or nonhuman milk. The length of BF to any extent (ABF) was defined as the last documented feeding of any breast milk to the infant. The lengths of EBF and ABF were technically interval censored because the exact time of discontinuation was not known. Because standard techniques do not allow for interval censoring, we coded discontinuation as occurring at the last reported feeding. This coding resulted in a slight overestimate of the hazard rate of discontinuation at any given time but did not bias comparison of the rates among the BMI groups or in relation to the covariates.
All women who attempted to breastfeed their infant in the hospital were given the minimum duration of EBF and ABF of 0.5 d. Women who fed 5/5 feedings from the breast before discharge were given the minimum duration of EBF as the infant’s age at discharge. Women who, before discharge, fed at least 1 of the last 5 feedings from the breast were given the minimum duration for ABF as the infant’s age at discharge. The maximum allowable duration of EBF and ABF was 180 d (6 mo), although BF may have continued beyond this time; these data were considered to be right censored. The outpatient records did not provide reliable information regarding the introduction of juice or solids, so these could not be considered. Right censoring was recorded for those infants who were lost to follow-up before 6 mo of age if still breastfed at the last visit.
Proportional-hazards regression was used to examine the RR of discontinuing BF over time as a result of maternal overweight or obesity in the prepregnant period. These analyses were performed separately, with duration of either EBF or ABF as dependent measures. All independent variables from the logistic-regression model were included in the proportional-hazards analyses. All dyads for which we were able to locate infant feeding information during the first 6 mo were included in these analyses (263 Black dyads, 235 Hispanic dyads).
|
RESULTS |
|---|
|
TOPABSTRACTSUBJECTS AND METHODSRESULTSDISCUSSIONLITERATURE CITED |
|---|
Site comparison. Comparisons were made between the characteristics of the dyads that met the selection criteria at the 2 participating hospitals (Table 1). Black women who gave birth at the hospital located closer to the inner-city core, which provided higher-risk care, had significantly greater participation in social programs, had higher rates of smoking in early pregnancy, and had lower rates of ever attempting to breastfeed their infant in the hospital than those who gave birth at the other site. Hispanic women who met the selection criteria and who delivered at the hospital closer to the inner-city core had higher rates of smoking, higher rates of gestational diabetes, were less likely to be born in the United States, and gave birth to infants with a slightly lower gestational age. There were no differences in maternal age, education, BMI, height, prepregnant weight, weight gain, infant birth weight or APGAR scores, duration of hospitalization, or rate of delivery by cesarean section between the 2 hospitals. Among those who attempted to breastfeed, there was no difference in the proportion of women who did so within the first 2 h postpartum, but a greater proportion of both Black and Hispanic women who delivered at the higher-risk hospital than at the lower-risk hospital were still breastfed at discharge.
|
Characteristics of BF attempters categorized by prepregnant BMI. Among the 640 Black women in our study population, 47.7% were of normal weight, 14.8% were overweight, and 37.5% were obese before conception; among the 587 Hispanic women, 55.4% were of normal weight, 16.7% were overweight, and 27.9% were obese. Prepregnant weight and BMI, and weight at delivery, but not height, differed between the normal-weight and other BMI categories for both racial/ethnic groups (Tables 2, and 3).
|
|
Overweight Hispanic women gained less weight during pregnancy, had about twice the rate of delivery by cesarean section and longer hospital stays postpartum than women of normal prepregnant BMI (Table 3). Obese Hispanic women had fewer years of education, more previous live births, gained less weight during pregnancy, were more likely to participate in at least 1 income-based social program, had higher rates of smoking, a 2-fold increase in the rate of gestational diabetes, were more likely to be born in the United States, had twice the rate of delivery by cesarean section, had longer maternal and infant hospitalizations postpartum, gave birth to larger infants, and were less likely to put their infant to breast within 2 h compared with their normal-weight counterparts.
Initiation of breastfeeding. Both Black and Hispanic women were discharged on average 2.3 d after the birth of their infants. Among Black women, 6.2% fed formula only during the last 5 feeds before discharge (5.1% for normal weight, 8.0% for overweight, 6.9% for obese). Among Hispanic women, 10.8% failed to provide any breast milk in the last 5 feeds before discharge (9.6% for normal weight, 12.2% for overweight, and 12.4% for obese women).
Among Black women, there was no significant association of prepregnant BMI with the odds of feeding formula only, or formula and breast milk, compared with breast milk only before discharge (Table 4). Among Hispanic women, there was no association between being overweight before pregnancy and the observed feeding pattern before discharge. Obese Hispanic women were more likely than normal-weight women to feed a combination of formula and breast milk vs. only breast milk before discharge (OR: 1.9; 95% CI: 1.2, 3.1, adjusted for covariates) but were no more likely than normal-weight women to feed formula only vs. breast milk only in the last 5 feeds before discharge (Table 4).
|
Duration of exclusive and any BF. Infants born to the 263 Black women choosing follow-up at the participating clinics averaged 10.0 d of age at the first outpatient visit (range 1–64 d, with 90% of infants seen by day 17), whereas infants of the 235 Hispanic women averaged 11.7 d of age (range 1–165 d, 90% of infants also seen by day 17) at the first visit.
Among Black women, the mean duration of EBF was 29 d but the median duration was only 8 d. The mean duration of ABF among Black women was 75 d, with a median duration of 57 d. Among Hispanic women, the mean durations of EBF and ABF were 17 and 48 d, respectively, with median durations of 3 and 17 d, respectively.
Proportional-hazards regression of ABF and EBF showed no effect of prepregnant BMI on the duration of EBF or ABF for Black women (Table 5). Among Hispanic women, the presence of obesity, but not overweight, before conception was significantly associated with shorter duration of both EBF (RR: 1.5; 95% CI: 1.1–2.0) and ABF (RR: 1.6; 95% CI: 1.1–2.1) (Table 5). The cumulative probabilities of continuing EBF and ABF over time for the 3 BMI categories among Black and Hispanic women are shown in Figure 2.
|
|
|
DISCUSSION |
|---|
|
TOPABSTRACTSUBJECTS AND METHODSRESULTSDISCUSSIONLITERATURE CITED |
|---|
In this research, we analyzed observed feeding behavior before discharge as a measure of BF success in the hospital. The infant medical record documents infant feeding in detail on a flowchart completed by nurses during each shift. We recorded the pattern of the last 5 feeds before discharge as an objective, directly observed measurement of the success or the failure of BF initiation in the hospital. The infant medical record also includes a discharge summary completed by the infant’s attending pediatrician, which reflects the physician’s assessment of the mother’s BF behavior or intent at the time of hospital discharge. This information, which we used in previous research (12), indicated that a smaller proportion of both Black and Hispanic women discontinued BF than was supported by observed feeding behavior in the hospital (data not shown). Therefore, we consider observed feeding behavior before discharge to be a more reliable indicator of early BF success.
The hospitals participating in the study provided obstetrical services to women, representing 71 and 74% of all live births in the city during 1998 and 1999, respectively. Information from local colleagues and local data (19) indicate we captured at least that proportion of the total births to minority women. The mix of Hispanic ethnicities was as expected from local data, and the vast majority of women were of Puerto Rican origin. Thus, the results of this study should be applicable to other Hispanic populations with high proportions of Puerto Rican women. However, the findings from this study might be less applicable to women from other Hispanic groups in which the cultural support for initiating and sustaining BF differs from that characteristic of Puerto Rican women.
In this study, 44.7% of the Black women and 58.5% of the Hispanic women attempted to breastfeed their infants. These percentages are similar to the 1996 values but less than the 2001 values reported by the Ross Laboratories Mothers Survey (2). The women for whom we had follow-up information were younger, less educated, and more likely to smoke and to participate in social programs than those who sought care elsewhere in this region. Thus, follow-up information reflects those women who are at highest risk of early BF cessation (3). Therefore, our estimates of BF duration may underestimate actual durations of exclusive and any BF. Follow-up care for the remainder of the subjects was scattered throughout the city, and practical considerations precluded the retrieval of such widely disseminated information.
Delivery by cesarean section could potentially confound the relationship between maternal obesity and BF success. Reports indicate that women who undergo cesarean section have lower rates of BF at discharge (20,21). In our study population, obese Black women and overweight and obese Hispanic women had higher rates of delivery by cesarean section than did their normal-weight counterparts. Women who undergo cesarean delivery experience more pain after delivery, receive more pain medication, and are more prone to postpartum complications than women who deliver vaginally (22). Additionally, their infants may be suckled later (14), as we observed in both the Black and Hispanic women in our sample. In the healthy dyads in our study, delivery by cesarean section was not associated with feeding method at discharge, and when it was added to models of BF initiation or duration in which BMI was the main effect, the significance of the association between prepregnant BMI and feeding method did not change. This suggests that delivery by cesarean section, although more prevalent in overweight or obese women, did not play a role in BMI-associated BF cessation in our study population.
By using the proportion of women who attempted to breastfeed and the rates of BF in our follow-up sample, we estimate that 24% of healthy Black women continued to exclusively breastfeed their infants at 7 d of age, while 22% of Hispanic women did so. At 6 mo, we estimated that 9% of Black and 6% of Hispanic women continued to breastfeed to some extent. Although our data may underestimate BF rates, the duration of BF among the minority women in our study falls short of recent national averages (2,23), particularly among the primarily Puerto-Rican Hispanic women in our sample, where the recent national data show 22.5–32.8% still BF at 6 mo. However, it has been reported that BF prevalence is less among Hispanic women of Puerto Rican than of Mexican American origin (24). Medical records do not provide information on factors such as acculturation that might be important in explaining why such a low proportion of this group of Hispanic women continued to breastfeed to 6 mo postpartum.
The duration of exclusive and any BF among Black women, although undesirably low, surpassed that of the Hispanic women in this sample, an unexpected observation. The percentage of Black women who attempted to breastfeed (45%) is smaller than the percentage among Hispanic women (59%) and even smaller than the 75% of Caucasian women in our previous work (12) who attempted to breastfeed. However, only 6.2% of the Black women who attempted to breastfeed their infant stop BF before discharge, a rate similar to that which we observed previously in Caucasian women (6.3%) and lower than that in the Hispanic women in this sample (10.8%). These Black women may differ from their Hispanic counterparts in knowledge, commitment to BF, confidence in their ability to breastfeed, or other characteristics not recorded in the medical records.
Since our initial observation of reduced BF success in rural Caucasian women (12), the association of BMI with BF outcomes has been confirmed in large studies, although this association was not examined separately by racial/ethnic group in any of these investigations. In a review of 287,000 births in London, investigators found that infants of overweight and obese women are less likely to be breastfed at discharge (25). Analyses of data from about 8000 American women collected in the early 1990s as part of NHANES III also showed that lower proportions of overweight and obese women ever breastfeed their infants and that duration of EBF and any BF among overweight and obese women was less than that among normal-weight women (23). In data from the Pediatric and Pregnancy Nutrition Surveillance Systems that were collected in the late 1990s, investigators confirmed, in about 13,000 subjects, that maternal obesity was associated with a shorter duration of BF (26).
In the present study, the effect of being obese among Hispanic women was smaller than that of being obese among rural Caucasian women (12). This may be because the medical, social, and cultural support for BF among urban Puerto Rican women differs from that of rural Caucasian women. In addition, the effect of prepregnant BMI may be difficult to detect if the normal-weight women who serve as the reference group fail to breastfeed for appreciable periods, as was the case for the Hispanic women studied here. The relatively small number of women in the overweight category also may limit our power to detect an association of overweight BMI and the establishment of exclusive BF in the hospital or the duration of exclusive or any BF (12).
It is of particular interest that we did not find the same association of BMI with BF outcomes in Black women that we found among Hispanic and Caucasian women. It is possible that being overweight or obese has a different biological meaning among Black women. That is to say, for a given BMI value, Black women may be less affected by its negative consequences than Caucasian women. The basis for this speculation is the recent report that Black women experience fewer years of life lost due to obesity than do Caucasian women (27). This result suggests that obesity has fewer negative consequences (mortality being the most extreme example) for Black than for Caucasian women. Given the study design and the type of data available in the present investigation, it is not possible to know why the Black women who chose to breastfeed were unresponsive to the negative effects of obesity that have been observed in Caucasian and Hispanic women, but this finding certainly warrants confirmation and further investigation.
Although not included in the analyses, BF after discharge was documented among 13 women who had never breastfed in the hospital. This reveals that even without suckling during early infant life, some women are able to breastfeed successfully; this warrants further study, particularly among Hispanic women who, by anecdotal reports from lactation counselors, prefer to "wait until the milk comes in" before beginning to nurse their infants. In the present climate of early postpartum discharge, if cultural beliefs encourage delayed initiation of BF, subgroups of women who could benefit greatly from BF intervention in the early days after discharge can be identified.
|
ACKNOWLEDGMENTS |
|---|
|
FOOTNOTES |
|---|
2 Supported by a grant from CREES, USDA 99–34324-8120.
4 Abbreviations used: ABF, breastfeeding to any extent; BF, breastfeeding; EBF, exclusive breastfeeding; NHANES, National Health and Nutrition Examination Survey; NICU, neonatal intensive care unit; OR, odds ratio; RR, relative risk; WIC, Supplemental Nutrition Program for Women, Infants and Children.
Manuscript received 14 November 2003. Initial review completed 5 January 2004. Revision accepted 28 April 2004.
|
LITERATURE CITED |
|---|
|
TOPABSTRACTSUBJECTS AND METHODSRESULTSDISCUSSIONLITERATURE CITED |
|---|
1. U.S. Department of Health and Human Services (2000) Healthy People 2010: National Health Promotion and Disease Prevention Objectives 2000 U.S. Department of Health and Human Services Washington, DC .
2. Ryan, A. S., Wenjun, Z. & Acosta, A. (2002) Breastfeeding continues to increase into the new millennium. Pediatrics 110:1103-1109.
3. Institute of Medicine (1991) Nutrition during lactation 1991 National Academy Press Washington, DC .
4. Lyon, A. J. (1984) Factors influencing breast feeding. Acta Paediatr. Scand. 73:268-270.[Medline]
5. Samuels, S. E., Margen, S. & Schoen, E. J. (1985) Incidence and duration of breast-feeding in a health maintenance organization population. Am. J. Clin. Nutr. 42:504-510.
6. Rassin, D. K., Markides, K. S., Baranowksi, T., Bee, D. E., Richardson, C. J., Mirkut, W. E. & Winkler, B. A. (1993) Acculturation and breastfeeding on the United States–Mexico border. Am. J. Med. Sci. 306:28-34.[Medline]
7. Ertem, I. O., Votto, N. & Leventhal, J. M. (2001) The timing and predictors of the early termination of breastfeeding. Pediatrics 107:543-548.
8. Taylor, J. S., Risica, P. M. & Cabral, H. J. (2003) Why primiparous mothers do not breastfeed in the United States: a national survey. Acta Paediatr. 92:1308-1313.[Medline]
9. Bentley, M. E., Dee, D. L. & Jensen, J. L. (2003) Breastfeeding among low income, African-American women: power, beliefs and decision making. J. Nutr. 133:305S-309S.
10. Rasmussen, K. M. (1998) Effects of under- and overnutrition on lactation in laboratory rats. J. Nutr. 128:390S-393S.
11. Rutishauser, I. H. & Carlin, J. B. (1992) Body mass index and duration of breast feeding: a survival analysis during the first six months of life. J. Epidemiol. Community Health 46:559-565.[Abstract]
12. Hilson, J. A., Rasmussen, K. M. & Kjolhede, C. L. (1997) Maternal obesity and breast-feeding success in a rural population of white women. Am. J. Clin. Nutr. 66:1371-1378.
13. Hilson, J. A., Rasmussen, K. M. & Kjolhede, C. L. (2004) High prepregnant body mass index is associated with poor lactation outcomes among white, rural women independent of psychosocial and demographic correlates. J. Hum. Lact. 20:18-29.[Abstract]
14. Chapman, D. J. & Perez-Escamilla, R. (1999) Identification of risk factors for delayed onset of lactation. J. Am. Diet. Assoc. 99:450-454.[Medline]
15. Rasmussen, K. M. & Kjolhede, C. K. (2004) Prepregnant overweight and obesity diminish the prolactin response to suckling in the first week postpartum. Pediatrics 113:e465 http://www.pediatrics.org/cgi/content/full/113/5/e465. [Accessed May 18, 2004.].
16. Mokdad, A. H., Serdula, M. K., Dietz, W. H., Bowman, B. A., Marks, J. S. & Koplan, J. P. (1999) The spread of the obesity epidemic in the United States, 1991–1998. J. Am. Med. Assoc. 282:1519-1522.
17. World Health Organization (1989) Protecting, promoting and supporting breastfeeding: the special role of maternity services. A joint WHO/UNICEF statement 1989 World Health Organization Geneva, Switzerland .
18. Institute of Medicine (1990) Nutrition during pregnancy 1990 National Academy Press Washington, DC .
19. Finger Lakes Health Systems Agency (1999) Nuestra Salud. A study of the health of the Hispanic community in the Rochester area 1999 Finger Lakes Health Systems Agency Rochester, NY .
20. Scott, J. A., Landers, M. C., Hughes, R. M. & Binns, C. W. (2001) Factors associated with breastfeeding at discharge and duration of breastfeeding. J. Paediatr. Child Health 37:254-261.[Medline]
21. Rush, D., Sloan, N. L., Leighton, J., Alvir, J. M., Horvitz, D. G., Seaver, W. B., Garbowski, G. C., Johnson, S. S. & Kulka, R. A., et al (1988) The National WIC Evaluation: evaluation of the Special Supplemental Food Program for Women, Infants, and Children. V. Longitudinal study of pregnant women. Am. J. Clin. Nutr. 48(2 Suppl):439-483.
22. Cunningham, F. G., MacDonald, P. C., Grant, N. F., Leveno, K. J., Gilstrap, L. C., Hankins, G.D.V. & Clark, S. L. (1997) Williams Obstetrics 20th ed. 1997 Appleton and Lange Stamford, CT .
23. Li, R., Ogden, C., Ballew, C., Gillespie, C. & Grummer-Strawn, L. (2002) Prevalence of exclusive breastfeeding among US infants: the Third National Health and Nutrition Examination Survey (Phase II, 1991–1994). Am. J. Public Health 92:1107-1110.
24. Stroup-Benham, C. A. & Trevino, F. M. (1991) Reproductive characteristics of Mexican-American, mainland Puerto Rican, and Cuban-American women: data from the Hispanic Health and Nutrition Examination Survey. J. Am. Med. Assoc. 265:222-226.[Abstract]
25. Sebire, N. J., Jolly, M., Harris, J. P., Wadsworth, J., Joffe, M., Beard, R. W., Regan, L. & Robinson, S. (2001) Maternal obesity and pregnancy outcome: a study of 287,213 pregnancies in London. Int. J. Obes. Relat. Metab. Disord. 25:1175-1182.[Medline]
26. Li, R., Jewell, S. & Grummer-Strawn, L. (2003) Maternal obesity and breastfeeding practices. Am. J. Clin. Nutr. 77:931-936.
27. Fontaine, K. R., Redden, D. T., Wang, C., Westfall, A. O. & Allison, D. B. (2003) Years of life lost due to obesity. J. Am. Med. Assoc. 289:187-193.
This article has been cited by other articles:
|
|
 |
|
  J. L Baker, K. F Michaelsen, T. I. Sorensen, and K. M Rasmussen High prepregnant body mass index is associated with early termination of full and any breastfeeding in Danish women Am. J. Clinical Nutrition, August 1, 2007; 86(2): 404 - 411. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Giovannini, G. Radaelli, E. Riva, and G. Banderali Low Prepregnant Body Mass Index and Breastfeeding Practices J Hum Lact, February 1, 2007; 23(1): 44 - 51. [Abstract] [PDF]
|
|
|
|
|
|
K. M. Rasmussen, V. E. Lee, T. B. Ledkovsky, and C. L. Kjolhede A description of lactation counseling practices that are used with obese mothers. J Hum Lact, August 1, 2006; 22(3): 322 - 327. [Abstract] [PDF]
|
|
|
|
 |
|
 J. A. Hilson, K. M. Rasmussen, and C. L. Kjolhede Excessive Weight Gain during Pregnancy Is Associated with Earlier Termination of Breast-Feeding among White Women J. Nutr., January 1, 2006; 136(1): 140 - 146. [Abstract] [Full Text] [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
