OXTR rs53576 variation with breast and nipple pain in breastfeeding women

Abstract

AbstractPurposeTo evaluate associations among breast and nipple pain sensitivity and candidate pain sensitivity single-nucleotide polymorphisms [SNPs], (COMT rs6269, rs4633, rs4818, rs4680 and OXTR rs2254298, rs53576) in breastfeeding women.DesignA secondary analysis of sixty women participating in a pilot randomized controlled trial of a pain self-management intervention.MethodsAll participants underwent standardized mechanical somatosensory testing for an assessment of pain sensitivity and provided baseline buccal swabs for genetic analysis. At 1, 2, and 6 weeks postpartum, women self-reported breast and nipple pain severity using a visual analogue scale.ResultsWomen with the minor allele OXTR rs53576 reported 8.18-fold higher breast and nipple pain severity over time. For every 1-unit increase in mechanical detection threshold and windup ratio, women reported 16.51-fold and 4.82-fold higher breast and nipple pain severity respectively. Six women with the OXTR rs2254298 minor allele reported allodynia.DiscussionThe presence of OXTR alleles in women with enhanced pain sensitivity suggests a phenotype of genetic risk for ongoing breast and nipple with potential for pain-associated breastfeeding cessation. Somatosensory testing identified women who reported higher breast and nipple pain during the first weeks of breastfeeding.Clinical ImplicationsPain sensitivity testing can help to identify women at risk of intolerable and/or ongoing breastfeeding pain who may benefit from additional support to mitigate early breastfeeding cessation. Targeted interventions are needed to address breastfeeding pain, including management of infant latch, positioning, and infection as well as support for self-management of breastfeeding pain.