The length of an average pregnancy is about 40 weeks. If you find yourself going past week 40 and inching into week 41 or 42, you might be getting a little anxious and wondering what’s going on. First of all, don’t worry. It is not unusual for pregnancies to last longer than 40 weeks. In fact, only 5% of women give birth on their due date1.
It is also important to keep in mind that your due date is an estimate. In the first trimester, you were given an approximate due date which is calculated by adding 40 weeks to the first day of your last menstrual period and combining this information with ultrasound imaging of the embryo or fetus. However, the result is just an educated “guesstimate” so you might actually be a little further behind than you think.
What does this mean for the baby?
In medical terminology, a pregnancy that lasts longer than 40 weeks may be referred to as postdates, post-term, or a prolonged pregnancy. Rest assured that most babies are born healthy, regardless of whether they arrive at term or later. However, there are some risks that begin to increase after about 41 weeks of pregnancy which is why your doctor and/or midwife will be keeping a closer eye on you during this time. Some of the risks associated with post-term babies include:
- Babies are at higher risk for problems with their blood glucose level (which can lead to a high birth weight).
- Babies may inhale meconium (fecal waste) while they are still in the tummy. This can cause breathing problems or infection at birth.
- Amniotic fluid levels can drop, and after 42 weeks, the placenta may not work as well as it did earlier.
- Babies born at 41 weeks and later are more likely to require the care of specialists and be admitted to the neonatal intensive care unit (NICU).
Although these risks increase for babies born a little later, it is important to remember that your birthing team will be monitoring you closely for any problems.
What happens next?
Here are a few things that will happen in the next few days1:
At the 40-week mark, your doctor or midwife will become more vigilant about monitoring the baby. Monitoring activities that your midwife may offer include:
- Counting how often your baby kicks during a specific time period
- A period of monitoring your baby’s heart rate using continuous fetal monitoring called a non-stress test
- Using an ultrasound scan to see how the baby is doing
If your doctor or midwife is satisfied that the pregnancy is progressing well and the baby is nice and healthy, then they’ll continue to monitor you closely until you go into natural labor.
If you reach the end of week 41 or the beginning of week 42 without going into labor, there is a good chance that your doctor will start discussing inducing labor. This means scheduling a date and time for you to come into the hospital where the labor process can be medically started. Whether or not you’ll be induced always depends on your own health, the status of your cervix, and the baby’s well-being.
Playing the waiting game
Playing the waiting game during the last few weeks of pregnancy is hard. You might feel impatient as you, your partner, and your family are anxiously waiting for the newest member of your family to arrive. At the same time, your body may also be physically uncomfortable with
- back pain,
- ankle swelling,
- difficulty sleeping, and
Here are a few things you can do to make the time go by a little more quickly:
- Now is a good time to shop for meals to stock up your freezer. After your baby is born you’ll be really glad to have lots of food in the house that is readily available, quick, and easy to make
- Sleep as much as you can. If you’re finding it difficult to sleep at night, take a nap during the day. Put your feet up, play some music, read a book. Just dozing is fine and will help to build up your energy stores for labor.
1- Canadian Institutes of Health Research. Association of Ontario Midwives. http://www.ontariomidwives.ca/images/uploads/client-resources/Postdates-Final.pdf