Labor Induction and Augmentation - Topic Overview
Sweeping of the membranes to help induce labor
Sweeping, or stripping, of the amniotic membranes is a simple first step used to try to start labor. Sweeping of the membranes separates the amniotic membrane from the uterus enough so that the uterus starts making prostaglandins. This type of chemical helps trigger contractions and labor. After the cervix is open a little, this step can easily be done in your doctor's or nurse-midwife's office.
Sweeping the membranes works in 1 out of 8 women. This means that it starts labor without needing to use oxytocin or artificially rupture the membranes.2 To sweep the membranes, your doctor or nurse-midwife reaches a gloved finger through the cervix. He or she then "sweeps" the finger around the inside edge of the opening.
Sweeping the membranes is low-risk. It does not raise your risk of infection. You may start to feel uncomfortable afterward, with irregular contractions and some bleeding.2
Artificial rupture of the membranes to induce labor
To help start or speed up labor, your doctor may rupture your amniotic sac (rupture of the membranes). This should only be done after your cervix has started to open (dilate) and the baby's head is firmly descended (engaged) in your pelvis. If the membranes are ruptured too early, there is a risk of the umbilical cord slipping down around or below the baby's head (cord prolapse). If the cord gets squeezed between the baby's head and the pelvic bones, the blood supply to the baby may be reduced or stopped.
To rupture your amniotic sac (amniotomy), your doctor inserts a sterile plastic device into your vagina. This device may look like a long crochet hook or may be a smaller hook attached to the finger of a sterile glove. The hook is used to pull gently on the amniotic sac until the sac breaks. This procedure is usually not painful. A large gush of fluid usually follows the rupture of the amniotic sac. The uterus continues to produce amniotic fluid until the baby's birth. So you may continue to feel some leaking, especially right after a hard contraction.