What is Amniotomy

Amniotomy is done to initiate and accelerate the labor process by rupturing the sac to release the fluid. It is however not a routine procedure but usually there are medical reasons behind this induction method. Amniotomy or artificial rupture of membranes (ARM) is not a painful procedure because of the absence of nerve endings in the amniotic sac. Some amount of discomfort is possible largely due to hand movements during the internal exams.

Reasons for Amniotomy

• By far the most common reason for amniotomy is to induce labor or speed up contractions in prolonged labors. Prostaglandin from the amniotic fluid is released which strengthens and increases the frequency of uterine contractions.
• To better scrutinize the fetal heartbeat by placing strategically an internal fetal electronic monitor on baby's scalp. This equipment will reliably record baby's heartbeat.
• To check the presence of meconium in the fluid, an indication of fetal distress, by observing the color of the amniotic fluid. Immediate action can be taken to suction the contents of baby's bowel should it be necessary.
• Mostly the sac tends to break on its own during the second stage of labor but infrequently baby can be born with an intact sac which must be quickly broken to allow baby to breathe.

Hazards of Amniotomy

• The possibility of confusion between false and true labor can ring high and one sure way to avoid unwarranted complication is to perform the procedure only after the 5-6 cm dilation is reached.
• Infection is another potential complication. The danger of fetal infection from vaginal exams and/or inserted instruments makes this procedure dangerous especially if the baby has been in the utero for more than 24 hours. (A course of antibiotics will be prescribed to cure the infection).
• Prolapse of the umbilical cord is a potential cause of fetal distress. The cord may slip between the head and the cervix. Rupturing membranes could then cause prolapse, making way for an emergency cesarean.

The Procedure

Amniotomy is usually performed in the hospital because fetal monitoring is necessary. A crochet-like long handled hook is inserted inside the vagina to rupture the sac during a pelvic exam. Next, the fluid will gush out. If performed without contractions, an oxytocin drip will be necessary. IV oxytocin is often used in the start with the rupture of membranes possibly being delayed until the mother is in more active labor. The following criteria must be fulfilled before beginning the procedure:

• The mother should be in active labor (five or more cm dilated)
• The mother should be at term.
• Baby's head should be engaged (0 station or more)
• Situation should warrant the procedure.