Cesarean section rates of expectantly managed were 22% in comparison to 19% for mothers who underwent elective induction of labor. Why, you might ask? Although the study doesn’t specifically cite any reasons, one possibility is that although the cervix may be more ripe (dilate easier) later in pregnancy, this advantage could be offset by the 1/2 pound to 1 pound of growth per week occurring over the last several weeks of pregnancy. Not to mention, according to birth weight trends over the last 80 years, infants born after 1970 average nearly a full pound larger than those that were born prior to 1970. If the average mom’s pelvis hasn’t enlarged adequately to accommodate this change, then the larger baby size may contribute to a portion of this difference.
Another noticeable difference in the outcomes for the two groups involved the rate of pregnancy-related blood pressure issues. Gestational hypertension and preeclampsia were present in 9% of the mothers who underwent induction, whereas 14% of expectantly managed mothers were affected. Potential concerns for pregnancy-induced hypertension (PIH) are that severe forms may cause kidney or liver dysfunction in moms-to-be as well as issues with anemia or low platelets, and in some cases, even stroke or seizures. For babies, blood supply and growth can be affected, and rarely, PIH can even cause premature separation of the placenta resulting in need for emergent delivery. Fortunately, these severe presentations are rare. Often PIH is diagnosed early, well before it reaches this stage, but that being said, it should still be taken seriously. This type of hypertension is the second-leading cause of maternal mortality after hemorrhage.
Lastly, babies born to mothers who underwent elective inductions at 39 weeks were slightly less likely to suffer from respiratory distress at 3% vs 4% for the expectantly managed group. Does that mean every first time mother should undergo elective induction at 39 weeks? Probably not. We have to remember that although this study appears to be rather well done with a large population, it is just one study, and for now, we are still waiting for the official recommendations from the Society of Maternal-Fetal Medicine (the high-risk pregnancy gurus). Still, it does appear that we may begin to see some advantages to elective induction. For now, the decision of how and when or even if should you undergo induction of labor should be made after discussion with your provider regarding the specifics of your medical history. Whether you proceed with induction or elect to wait, we hope your pregnancy leads to a happy, healthy mom and baby :)
Dr. Nick