What Risks Are Associated With Amniotomy?

Amniotomy refers to an artificial rupture of the membrane and involves deliberate rupturing of the amniotic sac to release the amniotic fluid. Amniotomy has the following purpose:

• To induce labor in conjunction with an oxytocin infusion
• To accelerate labor because amniotomy increases plasma prostaglandins
• To monitor the fetus or uterus

Amniotomy is avoided in the following conditions:

• Vasa Previa (a condition in which the fetal blood vessels cross or run near the internal opening of the uterus)
• Any contraindications to vaginal delivery
• The head of the child has not dropped deep into the pelvis
• Placenta previa (a condition where the placenta covers the opening of the cervix)
• Abnormal fetus positioning
• Cephalopelvic disproportion (a condition where the baby’s head or body is too large to pass through the mother’s pelvis)
• Multiple pregnancies
• Placenta previa (a condition where the placenta covers partially or fully the opening of the cervix)
• Transverse lie (the baby lies in a horizontal or sideways position of the uterus)
• Breech presentation (the baby is positioned to deliver feet or bottom first)
• Underlying medical conditions of the mother such as diabetes or high blood pressure
• Infection such as human immunodeficiency virus (HIV) or herpes affecting the mother
• Defects in the baby

Before the amniotomy, the physician will

• Explain the procedure including all the risks and alternative options.
• Obtain consent.
• Check for any conditions that oppose amniotomy.
• Put underpads to absorb the amniotic fluid.
• Conduct a vaginal examination.
• Elevate the hips on something soft and sterile.
• Monitor the fetal heart rate before and after the procedure.
• Monitor amniotic fluid characteristics.

In this procedure, the physician inserts a hook end of the rod through the vagina. The physician then directs it to the amniotic sac by feeling the amniotic membrane and presenting part. The physician makes a small opening in the amniotic sac with a plastic hook by applying gentle force. As the sac opens, the patient might feel a warm gush of fluid due to water breaking. The fluid may be odorless or colorless; however, the fluid may either contain a fetus’s first stools or blood-tinge. The physician shouldn’t remove their hand from the vagina immediately after the artificial rupture of the membrane because it would lead to cord prolapse. As the amniotic fluid ceases, and there is no cord dropping down in the vagina, the physician can remove their hand.

Amniotomy is performed if the cervix is partially opened or thinned (effaced) and the baby’s head is present deep in the pelvis. The fetal heart rate will be continuously monitored before and after the procedure.