Hypothesis: Smoking decreases breast feeding duration by suppressing prolactin secretion

Causes of Low Milk Supply: The Roles of Estrogens, Progesterone, and Related External Factors

Low milk supply (LMS) poses a significant challenge to exclusive and continued breastfeeding, affecting ∼10% to 15% of mothers. Milk production is intricately regulated by both endocrine and autocrine control mechanisms, with estrogens and progesterone playing pivotal roles in this process. In addition to endogenously produced hormones, external substances capable of interfering with normal hormonal actions, including phytoestrogens, mycoestrogens, synthetic estrogens, and hormonal contraceptives, can influence milk production. The effects of these extrinsic hormones on milk production may vary based on maternal body mass index. This comprehensive review examines the multifaceted causes of LMS, focusing on the involvement of estrogens, progesterone, and related external factors in milk production. Furthermore, it investigates the interplay between hormonal factors and obesity, aiming to elucidate the endocrine mechanisms underlying obesity-associated LMS. Insights from this review provide valuable perspectives for developing interventions to improve milk production and address the challenges associated with LMS.

Can Willingness to Breastfeed Be an Opportunity for Smoking Pregnant Women to Quit Smoking?

PURPOSE

Smoking during pregnancy and/or not breastfeeding have considerable negative health outcomes for the mother and infant. This descriptive and cross-sectional study determined the relationship between the prediction of smoking cessation success in pregnant women and their breastfeeding attrition prediction during lactation. The other aim of the study was to determine the predictor of smoking cessation success and the factors affecting breastfeeding attrition prediction.

METHODS

The present study was conducted with 131 smoking pregnant women. Data were collected using the Personal Information Form, the Smoking Cessation Success Prediction Scale, and the Breastfeeding Attrition Prediction Tool.

RESULTS

A statistically significant and positive correlation was revealed between the Smoking Cessation Success Prediction Scale and the positive breastfeeding attitude (r = 0.349, P < .01). Of the change in positive breastfeeding attitudes, 14.7% was explained by the prediction of smoking cessation success (adjusted R2 = 0.147).

CONCLUSION

The study revealed that the prediction of smoking cessation success increased with an increase in the positive breastfeeding attitude of smoking pregnant women.

Prenatal Exposure to Tobacco and Childhood Cognition and Behavior: Effect Modification by Maternal Folate Intake and Breastfeeding Duration

In this exploratory analysis, we assessed whether nutrition modified the association between prenatal exposure to tobacco and childhood cognition/behavior among 366 Colorado-based mothers and their offspring (born ≥ 37 weeks with birthweights ≥ 2500 g). Interaction by folate ( 5 months, but not for shorter durations. Our findings support the need for smoking cessation campaigns throughout pregnancy and throughout the postpartum period breastfeeding to reduce neurobehavioral risks in the offspring.

Nicotine exposure during breastfeeding alters the expression of endocannabinoid system biomarkers in female but not in male offspring at adulthood

Early nicotine exposure compromises offspring's phenotype at long-term in both sexes. We hypothesize that offspring exposed to nicotine during breastfeeding show deregulated central and peripheral endocannabinoid system (ECS), compromising several aspects of their metabolism. Lactating rats received nicotine (NIC, 6 mg/Kg/day) or saline from postnatal day (PND) 2 to 16 through implanted osmotic minipumps. Offspring were analyzed at PND180. We evaluated protein expression of N-acylphosphatidylethanolamide-phospholipase D (NAPE-PLD), fatty acid amide hydrolase (FAAH), diacylglycerol lipase (DAGL), monoacylglycerol lipase (MAGL) and cannabinoid receptors (CB1 and/or CB2) in lateral hypothalamus, paraventricular nucleus of the hypothalamus, liver, visceral adipose tissue (VAT), adrenal and thyroid. NIC offspring from both sexes did not show differences in hypothalamic ECS markers. Peripheral ECS markers showed no alterations in NIC males. In contrast, NIC females had lower liver DAGL and CB1, higher VAT DAGL, higher adrenal NAPE-PLD and higher thyroid FAAH. Endocannabinoids biosynthesis was affected by nicotine exposure during breastfeeding only in females; alterations in peripheral tissues suggest lower action in liver and higher action in VAT, adrenal and thyroid. Effects of nicotine exposure during lactation on ECS markers are sex- and tissue-dependent. This characterization helps understanding the phenotype of the adult offspring in this model and may contribute to the development of new pharmacological targets for the treatment of several metabolic diseases that originate during development.

Cigarette smoking during breastfeeding in Papua New Guinea: Prevalence and demographic and socio-economic predictors

BACKGROUND

Cigarette smoking during breastfeeding is reported to contribute to significant changes in the composition of breast milk not only by reducing its protective features but also affecting infants' response to breastfeeding and breast milk. However, studies on the prevalence of cigarette smoking and associated factors during breastfeeding are limited in Papua New Guinea (PNG). This study estimates the prevalence of cigarette smoking and its association with demographic and economic factors among breastfeeding women in PNG.

METHODS

We used weighted survey data from the 2016-2018 PNG Demographic and Health Survey (PNGDHS). A weighted sample of 3,822 women who were breastfeeding during the survey were included in the study. The outcome variable in the present study is current cigarette smoking. A multiple logistic regression analysis was used to estimate the association between current cigarette smoking status and socio-demographic and economic variables of breastfeeding women. The regression analysis results were reported using adjusted odds ratios (aOR) with their respective 95% confidence intervals (CIs).

RESULTS

From the weighted sample, the prevalence of cigarette smoking among breastfeeding women was 21.9%; of which 60.8% smoked daily. The mean number of cigarettes smoked in the last 24 hours preceding the survey was 6.05(SD = 5.99). Multiple logistic regression analysis revealed that breastfeeding women who were from the Momase (aOR: 2.337, CI: 1.786-3.058, p<0.001) and Highlands (AOR: 1.589, CI: 1.213-2.082, p = 0.001), had no religious affiliation (aOR: 3.665, CI: 1.235-10.877, p = 0.019), and households with daughters as household heads (aOR: 1.901, CI: 1.231-2.935, p = 0.004) and being in more than one union (aOR: 2.374, CI: 1.805-3.123, p<0.001) were significantly more likely to smoke cigarette compared to women from southern region, those affiliated to Anglican church, those with husband as household heads, and being in one union respectively.

CONCLUSION

Cigarette smoking among breastfeeding women in PNG is relatively high, and region of residence, religion, relationship to household head, and the number of unions remain independent predictors. Interventions should target the individual socio-economic and cultural contexts within which breastfeeding occurs.

Factors Associated with (Exclusive) Breastfeeding Duration-Results of the SUKIE-Study

The WHO European Region has the lowest exclusive breastfeeding (EBF) rates at 6 months in the world. In Austria, 55.5% of infants are EBF at the age of one week, although breastfeeding initiation is 97.5%. The study was conducted in 2019/2020 and considered 1214 mothers of legal age, who received four online questionnaires during their child's first year of life. The influence of different variables on total/exclusive breastfeeding duration were analysed by using a Cox model (Extension of the Cox Proportional Hazards Model) with time-dependent covariates. Multivariate analyses showed a significant influence of maternal BMI, lifestyle factors, such as smoking, and breastfeeding support on total breastfeeding duration. Remarkable differences in the median duration of any breastfeeding were found for breastfeeding support, where mothers breastfed twice as long. Support came primarily from hospital staff, the midwife and the partner. A higher monthly household net income, delivery in a baby-friendly certified hospital (BFH) and breastfeeding support were associated with a longer EBF duration. Obese mothers started feeding infant formula earlier and had a higher risk of early weaning. The results offer valuable insights into the importance of breastfeeding-friendly structures such as BFHs, a focus on breastfeeding aftercare and support of the mother to promote and protect breastfeeding.

Successful breastfeeding among women with intention to breastfeed: From physiology to socio-cultural factors

BACKGROUND

Even if women have intention to breastfeed, they do not always achieve a successful breastfeeding.

AIM

This study aims to analyse factors affecting breastfeeding prevalence among mothers that intended to breastfeed.

METHODS

This is a prospective observational study involving 401 pregnant women that intended to breastfeed (asked at the 20th week). Breastfeeding prevalence was evaluated in reference to health-related, socio-cultural factors and healthcare professionals' interventions at 1 month, 6 months and 12 months after birth. Data were analysed using descriptive statistical methods, bivariate logistic regression and multivariate logistic regression modelling.

RESULTS

Independent factors negatively affecting breastfeeding prevalence related to mothers' and newborns' health parameters and birth characteristics included smoking during pregnancy, anaemia and use of analgesia during labour. Regarding sociocultural parameters, being an immigrant, higher education level, intention to breastfeed before pregnancy, comfort with public breastfeeding and bedsharing were positively linked to breastfeeding, while teat or pacifier use in the first week was negatively linked. Regarding healthcare professionals' practices, mother and father/partner antenatal education course attendance and exclusive breastfeeding at the hospital were positively associated with breastfeeding.

CONCLUSION

Breastfeeding is a very complex phenomenon affected by multiple and diverse variables. Physiological factors only affect the short term (1st month), while middle and long term BF affecting variables are mainly identical and include mostly socio-cultural factors and also BF related practices, especially in the first days after birth. These data should help to develop more effective breastfeeding promotion strategies.

Can breastfeeding affect the rest of our life?

The breastfeeding period is one of the most important critical windows in our development, since milk, our first food after birth, contains several compounds, such as macronutrients, micronutrients, antibodies, growth factors and hormones that benefit human health. Indeed, nutritional, and environmental alterations during lactation, change the composition of breast milk and induce alterations in the child's development, such as obesity, leading to the metabolic dysfunctions, cardiovascular diseases and neurobehavioral disorders. This review is based on experimental animal models, most of them in rodents, and summarizes the impact of an adequate breast milk supply in view of the developmental origins of health and disease (DOHaD) concept, which has been proposed by researchers in the areas of epidemiology and basic science from around the world. Here, experimental advances in understanding the programming during breastfeeding were compiled with the purpose of generating knowledge about the genesis of chronic noncommunicable diseases and to guide the development of public policies to deal with and prevent the problems arising from this phenomenon. This review article is part of the special issue on "Cross talk between periphery and brain".

Is maternal cigarette or water pipe use associated with stopping breastfeeding? Evidence from the Jordan population and family health surveys 2012 and 2017-18

Background

Maternal smoking is suspected to have negative impacts on breastfeeding, such as decreasing the quantity of breast milk, and reducing vitamin and fat concentrations in the milk in the late lactation period. Cigarette and water pipe tobacco products are widely used in Jordan. We aimed to estimate the association between use of different tobacco products and the rates of current breastfeeding.

Methods

Data from Jordan’s Population and Family Health Surveys 2012 and 2017–18 were examined. Last-born, living children, aged < 25 months, from singleton births, ever breastfed, and living with their mother were included. The key outcome variables were the current breastfeeding (during last 24 h) and tobacco usage status [water pipe tobacco (hookah or narghile) and/or cigarette tobacco]. Complex sample multivariate logistic regression analysis was used to evaluate the association of the current breastfeeding with maternal smoking status.

Results

Overall, 6726 infants were included in the study. The current breastfeeding rate in infants aged 0–6 months was 87%, compared with 43.9% in infants aged 12–17 months and 19.4% in infants aged 18–24 months. Overall, 4.4% had mothers who smoked cigarettes, 5.4% smoked water pipe, and 1.6% both cigarettes and water pipe. The proportion of breastfed infants in non-smoking mothers was 57.7% and, those in smoke water pipe, cigarette and both tobacco products were 55.4, 44.9, and 51.0% respectively. Univariate analysis revealed that women cigarette smokers had a lower odds ratio (OR) for current breastfeeding (OR 0.60, 95% Confidence Interval [CI] 0.39, 0.92). Multivariate analysis revealed that maternal cigarette smoking was associated with a lower odds ratio for current breastfeeding compared with mothers who smoked neither water pipe nor cigarettes (AOR 0.51, 95% Cl 0.30, 0.87).

Conclusions

These results indicate that maternal smoking is associated with termination of breastfeeding, suggesting that structured training should be organized for healthcare professionals, expectant mothers and the general public about the association between maternal smoking and cessation of lactation.

Breastfeeding attitudes of refugee women from Syria and influencing factors: a study based on the transition theory

AIMS

This review was designed to systematically examine studies that determine the breastfeeding attitudes of Syrian mothers, and factors influencing their breastfeeding behavior.

METHODS

Studies published between 2010 and 2020 were examined using 'Syria OR Syrian mother OR Syrian refugee AND breastfeeding OR breastfeeding practices OR intention OR attitudes OR exclusive breastfeeding' as keywords on PubMed, GoogleScholar, MEDLINE, Scopus, ProQuest, National Thesis Center, Web of Science, ScienceDirect and CINAHL; and five publications meeting the inclusion criteria were included in the study. The researchers independently used JBI Critical Appraisal Checklist for Analytical Cross-Sectional Studies and JBI Critical Appraisal Checklist for Systematic Reviews and Research Syntheses, developed by Joanna Briggs Institute, to assess the methodological quality.

RESULTS

A total of 6546 studies were accessed as a result of the literature review. Five studies meeting the inclusion criteria were included in the study. Women who are in this process experience a developmental and situational transition according to the framework of Meleis' theory. Factors affecting their breastfeeding attitudes were grouped under three main and four sub-themes. It was determined that personal factors (socioeconomic factors, cultural beliefs, the significance of breastfeeding practice, preparation), factors related to the immediate environment and social factors affect these women's attitudes toward breastfeeding.

CONCLUSION

It was found that most of the Syrian women had positive attitudes toward breastfeeding; however, the breastfeeding duration was less than 6 months for most of the refugees. Furthermore, according to the results of the studies, refugee women from Syria who did not receive social support from their spouses and relatives stopped breastfeeding.

Tobacco smoking during breastfeeding increases the risk of developing metabolic syndrome in adulthood: Lessons from experimental models

Metabolic syndrome (MetS) is characterized by increased abdominal fat, dyslipidemia, diabetes mellitus and hypertension. A high MetS prevalence is strongly associated with obesity. Obesity is a public health problem in which several complex factors have been implicated, including environmental pollutants. For instance, maternal smoking seems to play a role in obesogenesis in childhood. Given the association between endocrine disruptors, obesity and metabolic programming, over the past 10 years, our research group has contributed to studies based on the hypothesis that early exposure to nicotine/tobacco causes offspring to become MetS-prone. The mechanism by which tobacco smoking during breastfeeding induces metabolic dysfunctions is not completely understood; however, increased metabolic programming has been shown in studies that focus on this topic. Here, we reviewed the literature mainly based in light of our latest data from experimental models. Nicotine or tobacco exposure during breastfeeding induces several endocrine dysfunctions in a sex- and tissue-specific manner. This review provides an updated summary regarding the hypothesis that early exposure to nicotine/tobacco causes offspring to become MetS-prone. An understanding of this issue can provide support to prevent long-term disorders, mainly related to the risk of obesity and its comorbidities, in future generations.

The relationship between gestational active and passive smoking and early postpartum complications

Objective: The studies especially on the postpartum effects of passive exposure to cigarette smoke are limited, although there are studies investigating early and late postpartum effects of active smoking during pregnancy. This study aimed to investigate the relationship between gestational active and passive smoking and early postpartum complications.Methods: This study was conducted with 217 women in the early postpartum period (first 7 days after birth) in a research hospital, gynecology and obstetrics clinic. Data were collected using the questionnaire form prepared in accordance with the literature by the face-to-face interview method. They were evaluated in the SPSS 23.0 program, and descriptive statistics, logistic regression analysis in multivariate analyses and multiple linear regression analysis were in the analysis of data.Results: In the study, it was found that active smoking was associated with cardiac anomalies (OR = 0.18, 95% = CI 0.03-0.91; p = .039), developmental retardation (OR = 0.11, 95% CI = 0.02-0.56; p = .008), respiratory distress (OR = 0.12, 95% CI = 0.02-0.58; p = .008), low birth weight (OR = 0.22, 95% CI = 0.08-0.57; p = .003) and premature labor (OR = 0.30, 95% CI = 0.16-0.59; p = .000) while passive smoking was associated with premature labor (OR = 0.47, 95% CI = 0.25-0.89; p = .021). It was determined that passive smoking was associated with gestational hypertension (OR 0.30, 95% CI = 0.09-0.85; p = .025). Nevertheless, it was found that active smoking negatively affected the infant's birth weight (p = .000), length (p = .040), head circumference (p = .000) and breastfeeding (p = .005).Conclusion: Gestational active and passive smoking has significant negative effects on maternal and infant health in the early postpartum period.

Nicotine directly affects milk production in lactating mammary epithelial cells concurrently with inactivation of STAT5 and glucocorticoid receptor in vitro

Nicotine from tobacco smoke is absorbed into the bloodstream and transferred into breast milk in breastfeeding mothers. Smoking causes a decrease in breast milk volume, adverse changes to the milk composition, and a shortened lactation period. Breast milk is produced by mammary epithelial cells (MECs) in mammary glands during lactation. However, it remains unclear whether nicotine directly affects milk production in lactating MECs. To address this issue, we prepared a culture model with high milk production ability and less-permeable tight junctions (TJs) by seeding mouse MECs on a cell culture insert. Lactating MECs showed expression of α2, α3, β2, and β4 of nicotinic acetylcholine receptors. The high concentration of nicotine at 10-100 μM inhibited β-casein secretion and caused abnormal localization of TJ proteins. We subsequently investigated whether nicotine at a physiological concentration could affect lactating MECs. Nicotine at 1.0 μM directly inhibited α- and β-casein secretion in lactating MECs concurrently with inactivation of STAT5 and glucocorticoid receptor without affecting the TJ barrier. Nicotine treatment also induced MEC apoptosis concurrently with inactivation of Akt. These results support the adverse effects of nicotine on breastfeeding in smoking mothers.

THE INFLUENCE OF PASSIVE TOBACCO EXPOSURE AND PHYSICAL EXERCISE ON BONE TISSUE OF YOUNG RATS

OBJECTIVE

The objective of this study is to investigate the effect of passive smoking during pregnancy and associated with swimming on bone area growth, bone mineral density (BMD), and bone mineral content (BMC).

METHODS

The offspring was grouped by control matrices (G1) and passive smokers (G2). The offspring was regrouped in eight subgroups, with exposure to smoking (2x/day) and physical exercise (1 session/day), respecting the group of matrices in: sedentary control (G1CS and G2CS), swimming control (G1CN and G2CN), sedentary passive smoker (G1FS and G2FS), and passive smoker swimmer (G1FN and G2FN). The area, BMD and BMC were measured by the tibia and femur and analyzed by densitometer. The results were analyzed by One-Way ANOVA test with Tukey post-test, with a significance level of 5%.

RESULTS

In the tibia BMC study, a better rate was observed in G2CN group when compared to G1CS, G1CN and G1FN (p ≤ 0.023). When assessing BMD in the femur, a higher density ratio was observed in G1FS group when compared to G2CS, G2CN, G2FS and G2FN (p<0.008). In the tibia study, the animals of the G1FS group had higher rates when compared to G2CS and G2FN groups (p≤0.007).

CONCLUSIONS

The model of male offspring exposed to passive smoking during fetal development showed a strong decrease in the analyzed parameters. Level of Evidence I, Randomized High Quality Clinical Trial With or Without Statistically Significant Difference, But Narrow Confidence Intervals.

Excessive maternal weight and practice of exclusive breastfeeding among women of low socioeconomic status

ABSTRACT Objective: To investigate the impact of excessive maternal weight on the early discontinuation of exclusive breastfeeding Methods: This is a longitudinal study including mother-infant dyads of low socioeconomic status receiving prenatal care in Health Care Centers in Porto Alegre, Rio Grande do Sul, Brazil. A structured questionnaire was administered to women in the last trimester of pregnancy, including weight measurements. Another interview was conducted six months after delivery, and data on infant feeding practices were collected and maternal height was measured. Maternal nutritional status was assessed using body mass index values according to gestational age. Discontinuation of exclusive breastfeeding before 4 months was considered a low duration rate Results: A total of 619 mother-infant dyads were evaluated. The prevalence of maternal overweight in the third trimester of pregnancy was 51%. The median duration of exclusive breastfeeding was 2.0 months. After adjustment for possible confounding factors, no association between maternal overweight and early discontinuation of exclusive breastfeeding was identified. Maternal smoking was identified as a risk factor (1.23, 95%CI=1.13-1.35) for early discontinuation of exclusive breastfeeding Conclusion: Excessive maternal weight was not confirmed as a risk factor for early discontinuation of exclusive breastfeeding. However, women who reported being smokers had a higher risk of early discontinuation of exclusive breastfeeding than those who did not smoke. This indicates the need for public health interventions to promote smoking cessation during pregnancy and in the postpartum period because of the deleterious effects of this habit on maternal and infant health.

Environmental risk factors for sudden infant death syndrome in Japan

While the prevalence of sudden infant death syndrome (SIDS) has decreased worldwide, this decline has plateaued recently. Strategies are needed to resume the constant decrease of SIDS in Japan. A prospective electrocardiographic screening program for infants was performed between July 2010 and March 2011. Parents of 4319 infants were asked about environmental factors related to SIDS through questionnaires at a one-month medical checkup and one year. Parental awareness of prone position, smoke exposure, and breast feeding as environmental factors were 81.4 %, 69.0 %, and 47.8 %, respectively. The prevalence of laying infants exclusively in a supine position was 96.7 %. At the one-month medical checkup, smoking prevalence was 41.7 % in fathers and 2.1 % in mothers. Maternal smoking prevalence was significantly increased at one year after (p < 0.001). Multivariate regression analysis showed that risk factors for new or continued maternal smoking habits were maternal smoking habits at one month (p < 0.001), paternal smoking habits one year later (p < 0.001), and younger maternal age (p = 0.02).

CONCLUSION

Most parents already avoid laying infants in the prone position, and parental smoking is still a SIDS risk concern in Japan. Smoking cessation programs should be further implemented for parents to decrease risks of SIDS in Japan. What is Known: • The prevalence of sudden infant death syndrome (SIDS) has decreased worldwide, however, this decline has plateaued recently. What is New: • Most infants were laid sleeping in the supine position (96.7 %) and were fed breast milk or a mix of expressed milk and formula (92.7 %), and 2.1 % of mothers smoked at the one-month medical checkup. • Maternal smoking prevalence significantly increased from the one-month medical checkup to one year later, and smoking mothers were more likely to feed infants by formula rather than breast milk. • Independent risk factors for new or continued maternal smoking habits included younger maternal age, maternal smoking habits at one month, and paternal smoking habits one year later.

Tobacco smoking and breastfeeding: Effect on the lactation process, breast milk composition and infant development. A critical review

Approximately 10% of women report smoking during pregnancy. The number of breastfeeding women who relapse back to smoking is even greater. Smoking may cause adverse changes to the milk's composition by not only reducing its protective properties, but also by affecting the infant's health. The pathophysiological mechanisms underlying these adverse effects are not entirely known. This article is a review of previous reports about the effects of smoking on the lactation process, breast milk composition and infant development. A systematic search for English language articles published until 2015 was made, using a MEDLINE data. The key search terms were "smoking and breastfeeding", "smoking and lactation", "smoking and milk composition", "nicotine and breast milk". Studies have shown that nicotine levels in breast milk of women who smoke are three times higher than those in the plasma levels. Breast milk volume is reduced and the duration of lactation period is shorter. Smoking causes adverse changes to the milk's composition by not only reducing its protective properties, but also affecting infants' response to breastfeeding and to breast milk.

Breastfeeding modifies the effects of environment tobacco smoke exposure on respiratory diseases and symptoms in Chinese children: the Seven Northeast Cities Study

To evaluate the potential effect of interaction between breastfeeding and environmental tobacco smoke (ETS) exposure on respiratory health, we studied 31 049 children (aged 2-14 years) from 25 districts of seven cities in northeast China. Parents of the children completed standardized questionnaires that characterized the children's histories of respiratory symptoms and illness, feeding methods, ETS exposure, and other associated risk factors. Breastfeeding was defined as having been mainly breastfed for 3 months or more. The results showed that the association of ETS exposure with childhood respiratory conditions/diseases was modified by breastfeeding, and the association for nonbreastfed children was stronger than that for breastfed children. In particular, for nonbreastfed children, the odds ratios (ORs) for the effect of current ETS exposure asthma was 1.71 (95% CI: 1.43-2.05); however, the OR for breastfed children was 1.33 (95% CI: 1.20-1.48), indicating that the interactions between breastfeeding and current ETS exposure on asthma were statistically significant (P = 0.019). When stratified by school (kindergarten vs. elementary school), breastfeeding was more protective for asthma-related symptoms among children from kindergarten. In conclusion, this study shows that breastfeeding is associated with smaller associations between ETS exposure and respiratory conditions in children, suggesting that breastfeeding reduces susceptibility to the respiratory effects of ETS.

Associations between perceived value of exclusive breastfeeding among pregnant women in the United States and exclusive breastfeeding to three and six months postpartum: a prospective study

BACKGROUND

Successful breastfeeding often starts with prenatally established intention. Yet, few mothers with the intention to exclusively breastfeed achieve their intended breastfeeding duration goal. This study examined the degree to which having a strong value of exclusive breastfeeding is associated with exclusive breastfeeding duration for at least 3 and 6 months postpartum among women who reported prenatal intention to exclusively breastfeed.

METHODS

Data were from the Infant Feeding Practices Study II, a longitudinal US national survey that followed maternal-infant dyads from pregnancy to 1 year postpartum. Bivariate and multivariate regression examined the degree to which strong maternal value of exclusive breastfeeding predicted exclusive breastfeeding duration.

RESULTS

Of the 1799 women who prenatally intended to exclusively breastfeed within the first few weeks postpartum, 34 and 9 % exclusively breastfed for at least 3 months and 6 months, respectively. Thirty-six percent of women reported strongly valuing exclusive breastfeeding out of which 46 % exclusively breastfeed to three months. In adjusted results, women who reported that they strongly value exclusive breastfeeding had more than twice the odds of exclusive breastfeeding for at least 3 months (Adjusted Odds Ratio [AOR] 2.29; 95 % confidence interval [CI] 1.84, 2.85) and for 6 months (AOR 2.49; 95 % CI 1.76, 3.53) compared to those who did not strongly value exclusive breastfeeding.

CONCLUSION

Valuing the benefits of exclusive breastfeeding during pregnancy is a strong independent predictor of actual exclusive breastfeeding duration. A minority of pregnant women strongly value exclusive breastfeeding and are able to exclusively breastfeed to 3 months even among women with established prenatal intention to exclusively breastfeed. Prenatal maternal education and environmental lactation support that extends into the postnatal period can promote longer duration of exclusive breastfeeding.

Early Breastfeeding Problems Mediate the Negative Association between Maternal Obesity and Exclusive Breastfeeding at 1 and 2 Months Postpartum

BACKGROUND

Compared with normal-weight women, women with obesity experience poorer breastfeeding outcomes. Successful breastfeeding among women with obesity is important for achieving national breastfeeding goals.

OBJECTIVES

The objectives were to determine whether the negative association between obesity and any or exclusive breastfeeding at 1 and 2 mo postpartum is mediated through breastfeeding problems that occur in the first 2 wk postpartum and if this association differs by parity.

METHODS

Mothers (1151 normal-weight and 580 obese) in the Infant Feeding Practices Study II provided information on sociodemographic and psychosocial characteristics, body mass index, and breastfeeding outcomes. At 1 mo postpartum, participants reported the breastfeeding problems they experienced in the first 2 wk postpartum from a predefined list of 17 options. We used factor analysis to condense these problems into 4 explanatory variables; continuous factor scores were computed for use in further analyses. We used maximum likelihood logistic regression to assess mediation of the association between obesity and breastfeeding outcomes through early breastfeeding problems.

RESULTS

No significant effect of obesity was found on any breastfeeding at 1 or 2 mo. At 1 mo postpartum, for both primiparous and multiparous women, there was a significant direct effect of obesity on exclusive breastfeeding and a significant indirect effect of obesity through early breastfeeding problems related to the explanatory mediating variable "Insufficient Milk" (throughout the remainder of the Abstract, this factor will be denoted by upper case notation). At 2 mo postpartum both the direct effect of obesity and the indirect effect through Insufficient Milk were significant in primiparous women but only the indirect effect remained significant in multiparous women.

CONCLUSIONS

Early problems related to Insufficient Milk may partially explain the association between obesity and poor exclusive breastfeeding outcomes. Women who are obese, particularly those reporting breastfeeding problems that grouped in the Insufficient Milk factor in the early postpartum period, may benefit from additional breastfeeding support.

The effects of electronic cigarette emissions on systemic cotinine levels, weight and postnatal lung growth in neonatal mice

Background/Objective

Electronic cigarette (E-cigarettes) emissions present a potentially new hazard to neonates through inhalation, dermal and oral contact. Exposure to nicotine containing E-cigarettes may cause significant systemic absorption in neonates due to the potential for multi-route exposure. Systemic absorption of nicotine and constituents of E-cigarette emissions may adversely impact weight and lung development in the neonate. To address these questions we exposed neonatal mice to E-cigarette emissions and measured systemic cotinine levels and alveolar lung growth.

Methods/Main Results

Neonatal mice were exposed to E-cigarettes for the first 10 days of life. E-cigarette cartridges contained either 1.8% nicotine in propylene glycol (PG) or PG vehicle alone. Daily weights, plasma and urine cotinine levels and lung growth using the alveolar mean linear intercept (MLI) method were measured at 10 days of life and compared to room air controls. Mice exposed to 1.8% nicotine/PG had a 13.3% decrease in total body weight compared to room air controls. Plasma cotinine levels were found to be elevated in neonatal mice exposed to 1.8% nicotine/PG E-cigarettes (mean 62.34± 3.3 ng/ml). After adjusting for sex and weight, the nicotine exposed mice were found to have modestly impaired lung growth by MLI compared to room air control mice (p<.054 trial 1; p<.006 trial 2). These studies indicate that exposure to E-cigarette emissions during the neonatal period can adversely impact weight gain. In addition exposure to nicotine containing E-cigarettes can cause detectable levels of systemic cotinine, diminished alveolar cell proliferation and a modest impairment in postnatal lung growth.

Cadmium increases the sensitivity of adolescent female mice to nicotine-related behavioral deficits

This study investigates spatial and nonspatial working memory, anxiety related behavior, and motor activities in cadmium and/or nicotine exposed female adolescent mice. P28 female adolescent mice (albino strain) were divided into four groups of five (n = 5) mice each. A set of mice (Nic) received subcutaneous nicotine (2.0 mg/kg) while a separate set (Cd) was treated with 2.0 mg/kg cadmium (subcutaneous). For the combined treatments of cadmium and nicotine, we administered 2.0 mg/kg Nicotine and 2.0 mg/kg of Cd. Subsequently, a separate group of animals (n = 5; control) received normal saline. The total duration of treatment for all groups was 28 days (P28–P56). At P56, the treatment was discontinued, after which the animals were examined in behavioural tests. Nicotine and cadmium increased the metabolism and food intake in the female adolescent mice. This also corresponded to an increase in weight when compared with the control. However, a combined nicotine-cadmium treatment induced a decline in weight of the animals versus the control. Also, nicotine administration increased the motor function, while cadmium and nicotine-cadmium treatment caused a decline in motor activity. Both nicotine and cadmium induced a reduction in memory index; however, nicotine-cadmium treatment induced the most significant decrease in nonspatial working memory.

Rotating night shift work, sleep quality, selected lifestyle factors and prolactin concentration in nurses and midwives

The pattern of secretion of many hormones, including prolactin, is dependent on the circadian rhythm. Night shift work involves exposure to artificial light at night and sleep deficiency, which in turn can affect prolactin synthesis. The aim of this study was to evaluate a possible association between night shift work characteristics, sleep quality, lifestyle factors and prolactin concentration, using data from a cross-sectional study of nurses and midwives. A cross-sectional study was conducted among 327 nurses and midwives currently working on rotating night shifts, and 330 nurses and midwives working during the day (aged 40-60 years) (388 premenopausal and 269 postmenopausal). Information about night shift work characteristics, lifestyle, reproductive factors, sleep pattern and other covariates was collected through a face-to-face interview, and from a one-week work and sleep diary completed by the subjects. Weight and height were measured. Prolactin concentration was measured in the morning blood sample using the electrochemiluminesence immunoassay method. Associations were analyzed using linear regression models adjusted for important confounders. Analyses were carried out separately in pre- and postmenopausal women. None of the night shift work or sleep characteristics was significantly associated with prolactin concentration. Prolactin concentration was significantly (p < 0.05) inversely associated with smoking and time of blood sample collection. These results were consistent among both pre- and postmenopausal women. Nulliparity was significantly positively associated with prolactin among premenopausal women, but inversely among postmenopausal. Age was related to prolactin among postmenopausal women only. Our study indicates that rotating night shift work is not associated with prolactin concentration. Smoking, parity, time of blood collection and age among postmenopausal women were significant determinants of prolactin.

Maternal smoking during pregnancy and growth in infancy: a covariance structure analysis

Background

Smoking during pregnancy is related to fetal constraint and accelerated postnatal growth. However, the pathways between these factors have not been clarified. Pathway analyses that link these factors can help us better understand the mechanisms involved in this association. Therefore, this study aimed to examine pathways between maternal smoking during pregnancy and growth in infancy.

Methods

Participants were singletons born between 1993 and 2006 in rural Japan. The outcome was the change in weight z-score between birth and 3 years of age. Pathways from maternal smoking and other maternal factors (such as maternal body mass index and work status) to growth in infancy via birth factors (such as birth weight and gestational age) and breastfeeding were examined using structural equation modeling.

Results

Complete data were available for 1524 children (775 boys and 749 girls). The model fit appeared adequate. Lower birth weight and non-exclusive breastfeeding mediated the association between maternal smoking during pregnancy and rapid growth in infancy. Maternal smoking was also directly linked to rapid growth in infancy (standardized direct effects 0.06, P = 0.002). Taking all pathways into account, the standardized total effect of maternal smoking on growth in infancy was 0.11.

Conclusions

Maternal smoking during pregnancy may both indirectly, through birth weight and breastfeeding status, and directly influence growth during infancy; however, there may be other pathways that have not yet been identified.