Why is an amniotomy performed?
Basically, there are four reasons for performing an amniotomy:
1. To induce labor or augment uterine activity. This is the most common reason for an amniotomy. The amniotic fluid is rich in a hormone called prostaglandin, and the bathing of the cervix by this fluid increases the strength and frequency of uterine contractions. Sometimes, if all of the above criteria for rupture are met, amniotomy is the least interventive way to get labor started or to make the labor more progressive and functional.
2. To enable the midwife or doctor to monitor the baby's heartbeat internally. A scalp electrode is placed against the baby's head and an ECG of the baby's heart beat can be directly recorded. This provides a much more reliable indication of the fetal well being than external monitoring alone. Internal fetal monitoring is often performed if there is a complication such as maternal disease, or if there is fetal distress or if the mother is being induced.
3. To check the color of the fluid. If there is a suspicion of the presence of meconium (the contents of the baby's bowel), certain preparations must be made. Suctioning must be set up and more personnel are required to be in attendance.
4. To avoid having the baby aspirate the contents of the amniotic sac at the moment of birth. Most often, the amniotic sac will break of its own accord, most often by the beginning of the second stage of labor. If it remains intact, it is sure to break with maternal pushing efforts. But in a rare case, the baby can be born with an intact bag that must be quickly broken to allow the baby to breathe.