Relationship between Use of Labor Pain Medications and Delayed Onset of Lactation

Background: Despite estimates that 83% of mothers in the United States receive labor pain medications, little research has been done on how use of these medications affect onset of lactation. Objective: To investigate whether use of labor pain medications is associated with delayed onset of lactation (DOL). Methods: We analyzed data from the 2005-2007 Infant Feeding Practices Study II, a longitudinal study of women from late pregnancy through the entire first year after birth (n = 2366). In multivariable logistic regression analyses, we assessed the relationship between mothers' use of labor pain medication/method and DOL (milk coming in > 3 days after delivery). Results: Overall, 23.4% of women in our sample experienced DOL. Compared with women who delivered vaginally and received no labor pain medication, women who received labor pain medications had a higher odds of experiencing DOL: vaginal with spinal/epidural only (aOR 2.05; 95% CI, 1.43-2.95), vaginal with spinal/epidural plus another medication (aOR 1.79; 95% CI, 1.16-2.76), vaginal with other labor pain medications only ([not spinal/epidural]; aOR 1.84; 95% CI, 1.14-2.98), planned cesarean section with spinal/epidural only (aOR 2.13; 95% CI, 1.39-3.27), planned cesarean with spinal/epidural plus another medication (aOR 2.67; 95% CI, 1.35-5.29), emergency cesarean with spinal/epidural only (aOR 2.17; 95% CI, 1.34-3.51), and emergency cesarean with spinal/epidural plus another medication (aOR 3.03; 95% CI, 1.77-5.18). Conclusion: Mothers who received labor pain medications were more likely to report DOL, regardless of delivery method. This information could help inform clinical decisions regarding labor/delivery.