Dr. MJ Bazos MD, Patient Handout
Pregnancy: What to expect when your due date has passed

When is a pregnancy considered overdue?

A pregnancy is usually completed in 38 to 42 weeks. "Post-term pregnancy," "prolonged pregnancy" and "post-date pregnancy" are all words used to describe a pregnancy that lasts beyond 42 weeks. About 5% of pregnancies are post-term.

How is my due date determined?

Your due date is estimated on the basis of the first day of your last period and on the size of your uterus (womb) early in your pregnancy. An ultrasound (also called a sonogram) may also give your doctor information about how far along your pregnancy is.
A reliable way to know your due date is to count from the first day of your last period. However, many women cannot remember the first day of their last period and are not sure when they got pregnant. In addition, it's usually hard to figure an accurate due date if you get pregnant soon after you stop taking birth control pills.
An early pelvic exam to measure the size of the uterus can be helpful. If you're not sure about the date of your last period or your uterus is smaller or larger than expected, an early ultrasound exam is helpful.

What if my pregnancy goes 1 week past the due date?

If your pregnancy lasts 1 week or more past your expected due date, your doctor will usually begin checking your baby more closely. Your doctor may check your baby's heartbeat by using an electronic fetal monitor, once or twice a week. In addition, an ultrasound exam might be done to look at the amniotic fluid around your baby. Ultrasound can also be used to see how much your baby is moving. You should continue to feel your baby move throughout your pregnancy. Decreased fetal movement may be a sign that you need to call your doctor.
In addition, your doctor may begin checking your cervix to see if it's dilated and thinned. Your doctor may also recommend inducing (starting) labor.

What if my pregnancy goes 2 weeks past the due date?

Many doctors induce labor if a woman is 2 weeks past her due date. This is to avoid complications, such as fetal distress or a baby that gets too large to deliver easily. Fetal distress occurs when the baby doesn't get enough oxygen. Then the baby's heart rate drops, and the baby can't tolerate the stress of labor.
If the cervix is closed and is not favorable for inducing labor, and the results of all of the tests of the baby are completely normal, some doctors will allow the pregnancy to go on for 1 more week.

How will my doctor induce labor?

Labor can be induced in some women by using a medicine called oxytocin (brand name: Pitocin), which causes contractions to start. Oxytocin is given through your veins. It starts to work in 1 to 2 hours.
Labor can also be induced in some women by "breaking the water," or rupturing the membranes that hold the amniotic fluid.