The when, why and how of initiating delivery
Many pregnant women envision themselves experiencing a normal labor and birth — a labor that starts spontaneously, a minimal need for intervention and a healthy mom and baby at the end.
But things don’t always go to plan. There may be unexpected discomforts, extra monitoring or unanticipated interventions. In some cases, labor needs to be induced, in which medications are given to initiate labor.
An induction is recommended when the risk of staying pregnant outweighs the risks of an induction — for example, if an expectant mom has hypertension or gestational diabetes or is 40 years of age or older. An induction might also take place if there are concerns about the baby’s health, such as IUGR (intrauterine growth restriction), or if a pregnant women is one to two weeks past her due date.
The Induction Timeline Varies
If your healthcare provider says you need an induction, the date it starts is not necessarily the day your baby will be born. In fact, it’s not uncommon for an induction to last several days, with multiple medications used throughout the process.
The length of your induction and the medications used are often dependent on your Bishop score — a number based on the characteristics of your cervix, including dilation, effacement (thinness), position and consistency, as well as how low your baby is in your pelvis. The higher the number (over eight is ideal), the more your cervix and body are ready for labor.
If your Bishop score is low, your provider might give you medication to soften and dilate the cervix. This medication is made up of prostaglandins and comes as a tablet, gel or vaginal insert. This part of the process is cervical ripening.
In some instances your provider may use a mechanical ripening method instead of a prostaglandin agent. In this case, a small flexible catheter is inserted into the vagina, up through the cervix into the uterus. A small balloon at the top of the catheter is then inflated with water. That balloon rests on the opening of the cervix in the lower part of the uterus. Sometimes this catheter has a second balloon that sits in the vagina applying pressure to the other side of the cervix.
Whether through medication or with a balloon, cervical ripening can last one to two days.
You may experience cramping during this phase — or sometimes even regular, painful contractions. Some women will go into labor with just these initial interventions, but the main goal of the ripening phase is to increase the Bishop score and prepare the body and cervix for labor.
Contracting the Uterus
Once the cervix is “ripe” and the Bishop score is in an acceptable range, the body and uterus need to be coaxed into labor. The medication used for this stage is Pitocin, a synthetic version of the hormone oxytocin that is naturally released during labor and breastfeeding and makes the uterus contract.
Pitocin runs continuously through an IV and starts at a very small dose. It stays on throughout labor, or until your body can sustain contractions on its own. While Pitocin is running, your baby will be monitored continuously, which means you may have two belts around your belly: one that listens to your baby’s heartbeat, and one that monitors for uterine contractions.
Pitocin helps your body go into labor gradually, sometimes over the course of many hours. Rest and stay hydrated. Consider watching a movie or reading a book during the early part of this phase.
It’s important to note that strong contractions — especially those triggered by Pitocin — can periodically cause your baby’s heart rate to drop. This is one reason for continuous monitoring while Pitocin is administered. Pitocin can be shut off if your baby is not tolerating the contractions and there are worrisome changes in his heart rate. Pitocin leaves the body in a matter of minutes, and most fetal heart rate issues resolve soon after it’s turned off.
There should be no restrictions regarding eating or drinking with the medications described here. That said, it often makes sense to have lighter meals in the early parts of labor, as you may be nauseous and experience vomiting in the active stages.
Being told that an induction is necessary can come as a disappointment to some — and a relief to others. In either case, if you are told that your labor might need to be induced, ask your provider what to expect so you can feel more at ease and in control when things get underway.
Sarah Kleinman, CNM, is a Certified Nurse Midwife in Boston who delivers babies at Beth Israel Deaconess Medical Center.