Long-term maternal benefits of breastfeeding

Breastfeeding is associated with improved health outcomes for mothers. The American Academy of Pediatrics and the American College of Obstetricians and Gynecologists (ACOG) recommend exclusive breastfeeding for the first six months of life with introduction of complementary foods at six months and continued breastfeeding through the infant’s first year of life and beyond as mutually desired.^1,2 Current breastfeeding rates are below the Healthy People 2020 (HP2020) target established by the United States Department of Health and Human Services (Table 1).^3,4 In addition, there are substantial racial and ethnic disparities in breastfeeding rates in the United States. Although no ethnic group has attained all the HP2020 breastfeeding goals, non-Hispanic black and American Indian/Alaska native women have the lowest rates.³

This article reviews recommendations for breastfeeding and current breastfeeding rates; positive maternal health outcomes associated with breastfeeding; and evidence-based practices that enable women to successfully achieve their breastfeeding goals. 

Breastfeeding and women’s health

Pregnancy is associated with metabolic changes such as increased insulin resistance, hyperlipidemia, and visceral fat accumulation. Persistence of the metabolic changes that occur during pregnancy has been theorized to increase a woman’s lifetime metabolic disease risk.⁵ Lactation may play a role in reversing these changes more rapidly. Also, adverse pregnancy outcomes such as preeclampsia, gestational diabetes and preterm delivery are associated with a higher maternal incidence of cardiometabolic diseases later in life. Breastfeeding is associated with risk reduction in these cardiometabolic diseases.⁶ For example, up to 50% of women with gestational diabetes develop Type 2 diabetes mellitus (T2D) within five years postpartum, and greater than one to three months of lactation is associated with approximately 80% reduction in the cumulative incidence of T2D at five years postpartum.⁷

The association between breastfeeding and women’s health has been studied extensively (Table 2).^8-10 A longer duration of breastfeeding has been associated with a risk reduction in breast cancer,^11-13 ovarian cancer,¹⁴ endometrial cancer,^15-17 metabolic syndrome,^18,19 hypertension,^20,21 myocardial infarction,^20,22 and T2D.^23,24 Sustained breastfeeding is associated with greater maternal benefit. In a recent cost analysis, Bartick et al. modeled maternal and child health outcomes using current national rates in comparison to optimal breastfeeding (defined as 90% of mothers exclusively breastfeeding each child for six months and continuing to breastfeed for 12 months). Across the lifetime of a cohort of women born in a single year, they found current suboptimal breastfeeding rates were associated with an excess of 2,619 premature maternal deaths (95% CI 1,978 to 3,259).¹⁰

Studies reveal an association between breastfeeding and improved maternal health; however, this association may not be causal. First, most studies are observational because it is unethical to randomize women to breastfeed or formula-feed. Randomized trials of breastfeeding have focused on types of support. As an example, the PROBIT study conducted in Belarus in the 1990s consisted of 17,046 mother-infant pairs. All mothers initiated breastfeeding and there was a small difference (8%-15%) in absolute breastfeeding rates between the intervention and control groups over the first postpartum year, limiting the ability to detect differences in health outcomes.²⁵ Secondly, outcomes may be confounded by differences in health behaviors: mothers who breastfeed are more likely to be white, married, better educated, wealthier, leaner, and less likely to use tobacco or recreational drugs when compared with women who do not breastfeed.⁵ Finally, baseline metabolic risk factors such as obesity and insulin resistance may negatively impact lactogenesis and breastfeeding duration.²⁶

Clinical practices that support breastfeeding 

Despite the maternal health benefits associated with breastfeeding, anticipatory guidance from ob/gyns is inconsistent: In one study, breastfeeding was discussed at 29% of initial prenatal visits and conversations lasted 39 seconds on average.²⁷ The World Health Organization/ UNICEF Ten Steps to Successful Breastfeeding increases breastfeeding success (Table 3).²⁸ The 10 steps are evidence-based practices that have been demonstrated to increase breastfeeding initiation and duration. Other strategies that improve breastfeeding rates include access to breast pumps, group prenatal classes, peer counseling, and clinic appointments for breastfeeding problems.^29-31

Providers are encouraged to initiate education on the benefits and management of breastfeeding from the first prenatal appointment and continue throughout pregnancy. Prescriptions for breast pumps and training in usage can be provided to women planning to return to work. Maternal risk factors for breastfeeding difficulties such as obesity, variations in breast anatomy and primiparity should we reviewed and anticipatory guidance provided.³² One common cause of iatrogenic early weaning is inaccurate information on medication use. Health care providers often provide inaccurate information about medication use during breastfeeding.^33,34 Most medications are compatible with breastfeeding, but inappropriate information may lead to unnecessary cessation of lactation.³⁵ Reliable up-to-date resources on medication in lactation include Lactmed (https://toxnet.nlm.nih.gov/newtoxnet/lactmed.htm), the Infant Risk Center (http://www.infantrisk.com), and MotherToBaby.org.

In the intrapartum period, providers should emphasize the importance of skin-to-skin contact in the immediate postpartum period and breastfeeding initiation within the first hour after birth. Postpartum, referral to sources of lactation support such as La Leche League, peer counselors, and hospital support groups may enable women to achieve their breastfeeding goals. Breast-feeding problems should be addressed by assessment of the mother-infant dyad in conjunction with an International Board-Certified Lactation Consultant.

Ob/gyns can play an important role by: (1) Developing knowledge and skills in basic lactation management; (2) Encouraging and supporting women to initiate and sustain breastfeeding; (3) Being a resource for mothers experiencing difficulties with breastfeeding; (4) Promoting the integration of the Ten Steps into maternity care; and (5) Advocating for policies that help women achieve their breastfeeding goals, such as paid maternity leave and break time for milk expression.¹

Conclusions 

Breastfeeding is associated with substantial differences in health outcomes for mothers. Lactation is a core component of reproductive physiology, and thus in the domain of women’s health providers.^1,36 Enabling women to meet their breastfeeding goals is therefore an integral part of women’s health care. 

Disclosures:

The authors report no potential conflicts of interest with regard to this article.

References:

• American College of Obstetricians and Gynecologists’ Committee on Obstetric Practice; Breastfeeding Expert Work Group. Committee Opinion No. 658: Optimizing Support for Breastfeeding as Part of Obstetric Practice. Obstet Gynecol. 2016 Feb;127(2):e86-e92.
• Eidelman AI, Schanler RJ, Johnston M, et al. Breastfeeding and the use of human milk. Pediatrics. 2012;129(3):e827-e841.
• Centers for Disease Control and Prevention. Rates of any and exclusive breastfeeding by sociodemographics among children born in 2013. 2016. http://www.cdc.gov/breastfeeding/data/nis_data/rates-any-exclusive-bf-socio-dem-2013.htm. Accessed 10/01/2016.
• Centers for Disease Control and Prevention. Maternal, Infant, and Child Health 2010; https://www.healthypeople.gov/2020/topics-objectives/topic/maternal-infant-and-child-health/objectives. Accessed 10/1/16, 2016.
• Stuebe AM, Rich-Edwards JW. The reset hypothesis: lactation and maternal metabolism. Am J Perinatol. 2009;26(01):081-088.
• Groer MWK-TK. Clinics in human lactation. How breastfeeding protects women’s health throughout the lifespan: the psychoneuroimmunology of lactation. Amarillo, TX: Hale Publishing; 2011.
• Tanase-Nakao K, Arata N, Kawasaki M, et al. Potential protective effect of lactation against incidence of type 2 diabetes mellitus in women with previous gestational diabetes mellitus: A systematic review and meta-analysis. Diabetes Metab Res Rev. 2017.
• Ip S, Chung M, Raman G, et al. Breastfeeding and maternal and child health outcomes in developed countries. AHRQ Publication No 07-E007. 2007.
• Chowdhury R, Sinha B, Sankar MJ, et al. Breastfeeding and maternal health outcomes: a systematic review and meta‐analysis. Acta Paediatrica. 2015;104(S467):96-113.
• Bartick MC, Schwarz EB, Green BD, et al. Suboptimal breastfeeding in the United States: Maternal and pediatric health outcomes and costs. Matern Child Nutr. 2016.
• Palmer JR, Viscidi E, Troester MA, et al. Parity, lactation, and breast cancer subtypes in African American women: results from the AMBER Consortium. J Natl Cancer Inst. 2014;106(10).
• Islami F, Liu Y, Jemal A, et al. Breastfeeding and breast cancer risk by receptor status--a systematic review and meta-analysis. Ann Oncol. 2015;26(12):2398-2407.
• Collaborative Group on Hormonal Factors in Breast Cancer. Breast cancer and breastfeeding: collaborative reanalysis of individual data from 47 epidemiological studies in 30 countries, including 50302 women with breast cancer and 96973 women without the disease. Lancet. 2002;360(9328):187-195.
• Sung HK, Ma SH, Choi JY, et al. The effect of breastfeeding duration and parity on the risk of epithelial ovarian cancer: A systematic review and meta-analysis. Jf Prev Med Public Health. 2016;49(6):349-366.
• Ma X, Zhao LG, Sun JW, et al. Association between breastfeeding and risk of endometrial cancer: a meta-analysis of epidemiological studies. Eur J Cancer Prev. 2015.
• Wang L, Li J, Shi Z. Association between breastfeeding and endometrial cancer risk: Evidence from a systematic review and meta-analysis. Nutrients. 2015;7(7):5697-5711.
• Zhan B, Liu X, Li F, Zhang D. Breastfeeding and the incidence of endometrial cancer: A meta-analysis. Oncotarget. 2015;6(35):38398-38409.
• Choi SR, Kim YM, Cho MS, Kim SH, Shim YS. Association Between Duration of Breast Feeding and Metabolic Syndrome: The Korean National Health and Nutrition Examination Surveys. J Womens Health (Larchmt). 2017;26(4):361-367.
• Ram KT, Bobby P, Hailpern SM, et al. Duration of lactation is associated with lower prevalence of the metabolic syndrome in midlife-SWAN, the study of women’s health across the nation. Am J Obstet Gynecol. 2008;198(3):268.e261-268.e266.
• Schwarz EB, Ray RM, Stuebe AM, et al. Duration of lactation and risk factors for maternal cardiovascular disease. Obstet Gynecol. 2009;113(5).
• Stuebe AM, Schwarz EB, Grewen K, et al. Duration of lactation and incidence of maternal hypertension: a longitudinal cohort study. Am J Epidemiol. 2011;174(10):1147-1158.
• Stuebe AM, Michels KB, Willett WC, Manson JE, Rexrode K, Rich-Edwards JW. Duration of lactation and incidence of myocardial infarction in middle to late adulthood. Am J Obstet Gynecol. 2009;200(2):138.e131-138.e138.
• Aune D, Norat T, Romundstad P, Vatten LJ. Breastfeeding and the maternal risk of type 2 diabetes: a systematic review and dose-response meta-analysis of cohort studies. Nutr Metab Cardiovasc Dis. 2014;24(2):107-115.
• Jager S, Jacobs S, Kroger J, et al. Breast-feeding and maternal risk of type 2 diabetes: a prospective study and meta-analysis. Diabetologia. 2014;57(7):1355-1365.
• Kramer MS, Chalmers B, Hodnett ED, et al. Promotion of Breastfeeding Intervention Trial (PROBIT): a randomized trial in the Republic of Belarus. Jama. 2001;285(4):413-420.
• Stuebe AM. Does breastfeeding prevent the metabolic syndrome, or does the metabolic syndrome prevent breastfeeding? Sem Perinatol. 2015 Jun;39(4):290-5.
• Demirci JR, Bogen DL, Holland C, et al. Characteristics of breastfeeding discussions at the initial prenatal visit. Obstet Gynecol. 2013;122(6):1263.
• Pérez-Escamilla R, Martinez JL, Segura-Pérez S. Impact of the Baby-friendly Hospital Initiative on breastfeeding and child health outcomes: a systematic review. Matern Child Nutr. 2016;12(3):402-417.
• Wouk K, Lara-Cinisomo S, Stuebe AM, Poole C, Petrick JL, McKenney KM. Clinical Interventions to Promote Breastfeeding by Latinas: A Meta-analysis. Pediatrics. 2016;137(1):1-15.
• Hawkins SS, Stern AD, Baum CF, Gillman MW. Evaluating the impact of the Baby-Friendly Hospital Initiative on breast-feeding rates: a multi-state analysis. Public Health Nutr. 2015;18(02):189-197.
• Patnode CD, Henninger ML, Senger CA, Perdue LA, Whitlock EP. Primary care interventions to support breastfeeding: Updated evidence report and systematic review for the us preventive services task force. JAMA. 2016;316(16):1694-1705.
• Committee AoBMCP. ABM Clinical Protocol# 2 (2007 revision): Guidelines for hospital discharge of the breastfeeding term newborn and mother:“the going home protocol”. Breastfeed Med. 2007 Sep;2(3):158-65.
• Davanzo R, Bua J, De Cunto A, et al. Advising mothers on the use of medications during breastfeeding: need for a positive attitude. J Human Lact. 2016 Feb;32(1):15-9.
• Hussainy SY, Dermele N. Knowledge, attitudes and practices of health professionals and women towards medication use in breastfeeding: A review. Int Breastfeed J. 2011;6:11.
• Sachs HC, Frattarelli DA, Galinkin JL, et al. The transfer of drugs and therapeutics into human breast milk: an update on selected topics. Pediatrics. 2013;132(3):e796-e809.
• Committee AoBMP. Clinical protocol number #19: Breastfeeding promotion in the prenatal setting. Breastfeed Med. 2009