Kenkel, W.M. et al. Sci. Adv. 5, eaav2244 (2019)
Women going into labor naturally produce oxytocin, a hormone that promotes contractions as well as bonding after birth. Many also receive exogenous sources to induce or augment the labor process. What impact that extra oxytocin might have on the baby after the fact isn’t entirely clear, so researchers recently looked to an animal to learn more: prairie voles, known for their close social relationships. Plasma levels of oxytocin rose in the vole fetus when the hormone was administered to the pregnant dam. The effects appeared to be long lasting, at least in males: over their lives, male voles who received extra oxytocin in utero were more social towards other adults as well pups, with potential epigenetic signatures of oxytocin exposure observed in the brain.