Comparison of levonorgestrel level and creamatocrit in milk following immediate versus delayed postpartum placement of the levonorgestrel IUD

Abstract Background Breastfeeding and postpartum contraception critically influence infant maternal health outcomes. In this pilot study, we explore the effects of timing duration levonorgestrel exposure on milk lipid content to establish baseline data for future research. Methods This sub-study recruited a balanced convenience sample from 259 participants enrolled in parent randomized controlled trial comparing immediate delayed (4–8 weeks) IUD placement. All planned breastfeed, self-selected participation, provided first at 4–8 weeks (before placement group) second four later. We used Wilcoxon rank sum (inter-group) signed (intra-group) tests compare (creamatocrit) levels between groups time points. Results 15 group 17 with 10 12, respectively, providing both early late samples. Initially, median concentration (n = 10) (32.5 pg/mL, IQR : 24.8, 59.4) exceeded that 12) (17.5 0.0, 25.8) ( p 0.01). Four later, values aligned: 26.2 pg/mL 20.3, 37.3) vs. 28.0 25.2, 40.8). Creamatocrits were similar timepoints. Conclusions Immediate results steady, low without apparent content. These findings provide initial support safety initiation, though study was not powered detect noninferiority groups. Trial Registration registered ClinicalTrials.gov (Registry No. NCT01990703) November 21, 2013.