Here's How Far You Should Go Past Your Due Date, According To Science

by Steph Montgomery

When I was pregnant for the first time, I watched my baby's due date come and go without so much as a subtle sign childbirth was in my immediate future. So, like any first-time mom-to-be, I freaked out. Not only was I so over being pregnant, but I started to worry that I would have to be induced, or worse, that my baby wasn't OK. I knew that having your baby early was dangerous, but I had no idea how far past your due date was OK.

While a typical pregnancy lasts about 40 weeks (give or take) from a person's last menstrual period, only a small number of people actually give birth on their baby's due date. Mayo Clinic reports that a delivery between 37 weeks and 42 weeks gestation is considered full-term. After 42 weeks it is consider post-term or post-dates. Different obstetrics providers have different philosophies and policies related to how far they'll let their patients go past their due dates before they recommend induction of labor, with some preferring a "wait and see" approach, known as expectant management.

As CNN reports, many providers currently recommend induction at 41 weeks gestation, due to increased risk of infant mortality and health complications. Other providers won't induce labor unless there's a medical need, believing that induction is to be avoided unless absolutely necessary. New research published in August 2018 in the New England Journal of Medicine shows that risks of complications for both low-risk pregnant women and their babies are lower for moms who are induced at 39 weeks when compared to waiting for labor to start on it's own. This has lead a group of obstetricians to start talking to women about the risks of waiting and, as a result, recommending earlier elective inductions.

According to Mayo Clinic, different factors increase your chances of going past your due date, including being pregnant for the first time, uncertainty about your due date, or surprisingly, being pregnant with a boy. While you aren't considered post-term until you reach 42 weeks gestation (or two full weeks past your due date), the same site notes that babies born between 41 and 42 weeks gestation are at greater risk of health problems, including inhaling meconium or low amniotic fluid. Babies that go past their due dates are also more likely to be larger than average, which can increase the risk of a C-section or tearing during birth.

While some providers encourage women to wait for labor, others are changing the way they counsel pregnant women about going past their due date, and for some very good reasons. At the 2016 annual meeting of the American College of Obstetricians and Gynecology, two OB-GYNs — Charles J. Lockwood, MD of the University of South Florida, and Errol R. Norwitz, MD, PhD of Tufts University School of Medicine — were asked to come prepared to debate the topic of the pros and cons of induction of labor at 39 weeks. Surprisingly, both of their research reached the same conclusion — while there are risks of induction before 39 weeks gestation, there's absolutely no reason not to induce women with uncomplicated pregnancies at that point. In fact, the risks to both the pregnant person and their baby go up dramatically after 39 weeks pregnancy.

The research for recommending induction on — or even before — your baby's due date is pretty compelling. According to a Cochrane Review including over 30 studies, women who continue their pregnancies past 41 weeks gestation face considerably more risks than those who choose to be induced. Those risks include C-section delivery and your baby having to spend some time in the neonatal intensive care unit (NICU). In contrast, induction at 39 weeks was associated with a lower infant mortality rate, but an increased risk of an assisted delivery.

Similarly, a new study published in August 2018 in the New England Journal of Medicine showed that women who chose elective induction at 39 weeks had fewer complications, including prenatal hypertension, and fewer C-sections than those who chose to wait. Surprisingly, women who were induced also reported feeling less pain and more in control during labor than those in the expectant management group.

As CNN reports, because your risk of pregnancy complications such as uterine infections, preeclampsia, and problems with your placenta increase when you go past your due date, it's important to continue to get prenatal care and discuss your options with your provider. According to Mayo Clinic, once you've reached your due date your OB-GYN or midwife might order tests to make sure your baby is healthy, and might suggest an induction if medically necessary or if you decide it's right for you.

In the end, the decision to wait for labor to start on it's own or get induced if you pass your baby's due date is one that you will make with your doctor or midwife. It's important to know the risks, though, so you can make an informed choice.