Kummer, Leslie

Introduction: Lithium remains a gold standard treatment for bipolar disorder including during peripartum. Historically, guidelines advised against breastfeeding while taking lithium though recent data suggest it is acceptable for a healthy infant. Lack of awareness of acceptability contributes to decreased patient and clinician comfort and low breastfeeding rates. We report current breastfeeding rates, monitoring practices, and infant outcomes with lithium exposure in breastmilk at our institution. Methods: A retrospective chart review was conducted at a single academic medical center using records from 2013 to 2023. Electronic medical records were queried to identify patients prescribed lithium postpartum. Data were collected on timing of lithium initiation, lithium dose and concentration, breastfeeding status, and infant outcomes. Results: A total of 18 cases of lithium use in the postpartum period were identified. A total of 39% ( n = 7) of patients taking lithium postpartum breastfed. Most patients, 61% ( n = 11), initiated lithium prior to pregnancy, 11% ( n = 2) initiated during pregnancy and 27% ( n = 5) started postpartum. Four infant charts were reviewed with no reports of adverse events. Of these infants, average maternal lithium dose was 750 mg daily, with an average maternal serum lithium concentration of 0.62 mmol/L and average infant serum lithium concentration of 0.16 mmol/L. Conclusion: Our data demonstrate most patients using lithium postpartum have been taking lithium long-term and are not breastfeeding. Lithium exposure in breastmilk appears to be tolerated by healthy infants. There is a need for ongoing research and education on acceptability and infant monitoring recommendations to support patients who would like to breastfeed while on lithium.

Objective: We aimed to investigate prospective associations between milk bioactives related to metabolic health (glucose, insulin, leptin, C reactive protein [CRP], and interleukin 6 [IL-6]) and incident formula initiation at 3 and 6 months postpartum. Design: This study included 363 mother–infant dyads who were fully breastfed at 1 month and participated in the prospective Mothers and Infants Linked for Healthy Growth study from pregnancy to 6 months postpartum. Associations between milk glucose, leptin, insulin, CRP, and IL-6 at 1 and 3 months and incident formula feeding (FF) at 3 and 6 months, respectively, were tested using multiple logistic regression, adjusting for numerous potential confounders such as maternal age and prepregnancy body mass index. Results: At 3 months postpartum, 1-month glucose (odds ratio [OR] 0.45 [95% confidence interval (CI): 0.27–0.75], p ≤ 0.01) and smaller decreases in glucose from 1 to 3 months (OR 0.51 [95% CI: 0.28–0.92], p = 0.03) were associated with lower odds of FF, whereas 1-month leptin (OR 2.30 [95% CI: 1.30–4.07], p < 0.01) and larger increase in insulin (OR 1.86 [95% CI: 1.23–2.81], p < 0.01) and leptin (OR 2.17 [95% CI: 1.29–3.68], p < 0.01) from 1 to 3 months were associated with increased odds of FF. At 6 months, insulin increases (OR 2.08 [95% CI: 1.03–4.17], p = 0.04) were associated with higher odds of FF. Conclusions: In a cohort of women with established lactation, 1-month milk glucose, insulin, and leptin predicted initiation of FF at 3 months. Early milk composition may provide a window into mammary gland function, allowing identification of women at risk of not meeting their breastfeeding goals.

Objective: To explore, in a large, nationally representative U.S. sample of children, potential independent associations between social and community factors and breastfeeding outcomes, using the Social Ecological Model as a theoretical framework. Materials and Methods: A secondary data analysis of the 2011–2012 National Survey of Children's Health was conducted ( N = 29,829). Multivariate logistic regression was performed to estimate associations between predictor variables (parental emotional support, neighborhood social support, neighborhood safety, neighborhood amenities, and medical home) and breastfeeding outcomes (breastfeeding initiation [BFI] and exclusive breastfeeding for 6 months [EBF6m]). For predictor variables reaching statistical significance in the adjusted models, we performed subgroup analyses by race-ethnicity. Results: After adjusting for individual- and family-level sociodemographic and maternal-child health factors, living in a neighborhood with 4 amenities was associated with 1.54 (95% confidence interval [CI] 1.06–2.23) times the odds of BFI, compared to children living in neighborhoods with no amenities. There was a negative association (adjusted odds ratio [aOR] 0.83; 95% CI 0.70–0.99) between neighborhood social support and BFI, although living in a supportive neighborhood was associated with 1.37 (95% CI 1.11–1.69) times the odds of EBF6m. There was a negative association (aOR 0.71; 95% CI 0.54–0.93) between perceived neighborhood safety and EBF6m. The observed associations differed by race-ethnicity. Conclusion: Community-level structural and social support factors influence breastfeeding outcomes, independent of previously described individual level sociodemographic factors, and the observed associations differ by race-ethnicity. These findings have implications for the development of “breastfeeding-friendly” communities and public policies.