One of the first things a woman will want to know after confirming a pregnancy is when she is due to give birth. It’s important to remember that the due date is just an estimate of when your baby will be born, and not all babies follow the predicted schedule. Many women go past their due date.
The normal length of a human pregnancy is roughly 40 weeks, although most babies are born between 38 and 42 weeks. Due date can be calculated several ways. A large percentage of doctors will predict a due date by counting 40 weeks from the first day of the woman’s last menstrual period. Doctors can also use an ultrasound and measuring of the uterus to help determine how old a fetus is. Even if a woman passes the expected delivery date, that does not medically mean she is post due.
Although the due date is based on 40 weeks, the American College of Obstetricians and Gynecologists estimates that only a very small percentage of babies are born on their due date. A mix-up with the date of the last menstrual period or irregular ovulation may make predicting the date less accurate.
Most babies born after their due date are healthy. However, going past 42 weeks of pregnancy can have some risks. Babies may be larger, which can make delivery more complicated. There is an increased need for C-sections with post-due babies. Other risks include a decrease in amniotic fluid and the risk of meconium aspiration. Meconium is the waste expelled when a baby has a bowel movement in the womb. The meconium gets in the amniotic fluid, and the baby may breath it in during birth.
Since complications are possible, your doctor may order certain tests to monitor your baby if you go past your due date. Some doctors will wait until after the 41st week to begin monitoring. Your doctor can monitor the baby through an ultrasound or by doing a non-stress test. This is an electrical monitoring of your baby, which can measure how the baby moves and his heart rate. This test can help identity fetal distress.
Although doctors’ views may differ slightly on when to induce a woman after her due date, the American College of Obstetricians and Gynecology recommends induction by 42 weeks. Induction may be done earlier if the baby shows signs of distress during monitoring. A doctor may induce labor in a few ways, including rupturing the bag of water or giving the medication pitocin, which helps start contractions.