Oxytocin receptor DNA methylation is associated with exogenous oxytocin needs during parturition and postpartum hemorrhage.

Oxytocin is a hormone produced by the body during childbirth and can cause contractions of the uterus (womb). Synthetic oxytocin is used as a medicine for stimulating or increasing uterine contractions and controlling bleeding after birth. The oxytocin receptor gene, which enables the body to use oxytocin, can be altered by a chemical modification called DNA methylation. We found that the those who bled more during childbirth had higher oxytocin receptor gene DNA methylation compared to those who had normal bleeding. Higher methylation was also linked to needing greater amounts of oxytocin during labor to achieve vaginal birth and control bleeding. These findings identify that certain problems during birth may be related to oxytocin receptor gene methylation. This research could lead to improvements in how versions of oxytocin are used during the birth process by using the amount of oxytocin receptor gene methylation to predict people who may have problems with uterine contractions or bleeding.