Often referred to as the “hormone of love,” oxytocin plays an important role in childbirth, maternal behavior, lactation, social affiliation, and sexual pleasure. Levels of oxytocin, a neuropeptide produced by the hypothalamus and released into the bloodstream via the pituitary gland, rise around the time of delivery. These levels remain high after delivery, specifically increasing in response to warm social or physical contact.
Synthetic oxytocin, also known as Pitocin, is frequently administered during delivery for the purpose of inducing labor and preventing excessive post-delivery bleeding. One might hypothesize, based on the role that natural oxytocin plays, that women receiving oxytocin might receive some degree of benefit from the peri-partum use of Pitocin; however, a recent study calls this hypothesis into question.
This study used population-based data available through the Massachusetts Integrated Clinical Academic Research Database (MiCARD) in order to retrospectively examine the relationship between peripartum synthetic oxytocin administration and the development of depressive and anxiety disorders within the first year postpartum. While the authors expected to observe that women exposed to synthetic oxytocin in this cohort (n = 9,684) would have a reduced risk of postpartum depressive and/or anxiety disorders than those without any exposure (n = 9,684), they actually found the opposite.
In women with a history of depression or anxiety disorder prior to pregnancy, the researchers observed that exposure to peripartum oxytocin increased the risk of postpartum depression or anxiety disorder by 36% (relative risk (RR): 1.36; 95% confidence interval (95% CI): 1.20–1.55). In deliveries to women with no history of prepregnancy depressive or anxiety disorder, the risk of postpartum depression or anxiety was increased to a similar extent (RR: 1.32; 95% CI: 1.23-1.42). This is not a huge increase but it is statistically significant.
Do these findings mean we should not use synthetic oxytocin in this setting?
I have seen a few articles in the lay literature suggesting that, based on the findings of this study, we need to be more cautious in using synthetic oxytocin or Pitocin during labor and delivery. However, there are several important things to keep in mind. First of all, the observed increase in risk was relatively small. Because the use of Pitocin may be associated with other complications, we also cannot rule out the possibility that these complications during labor and delivery may also contribute to increased risk of postpartum depression and anxiety. Furthermore, Pitocin is used when medically indicated, to advance labor and to reduce the risk of postpartum hemorrhage, and avoiding its use in this setting may increase the risk of other life-threatening complications.
Ruta Nonacs, MD PhD
Kroll-Desrosiers A, Nephew BC, Babb JA, Guilarte-Walker Y, Moore Simas TA, Deligiannidis KM. (2017) “Association of peripartum synthetic oxytocin administration and depressive and anxiety disorders within the first postpartum year.” Depression and Anxiety, in press,DOI: 10.1002/da.22599.