Detachment of membranes, a technique to induce labor and childbirth

When the baby is delayed, the doctor or midwife sometimes offers to start the contractions by practicing the technique known as "detachment of the membranes". What does this method consist of? When is it decided? Does it involve risks? And how effective is it? The answers with Dr Jérôme Massardier, gynecologist-obstetrician at the CHU de Lyon.

What is membrane detachment?

Detachment of the membranes (or "stripping" in English) is a manual technique whose principle is to trigger contractions to accelerate the onset of childbirth. In theory, therefore, it is only practiced if the work has not started. " Logically, the technique is also of no interest when there is a rupture of the water pocket », Explains Dr Massardier. To do this, the doctor or midwife crosses the cervix in its entirety to detach the membranes of the amniotic sac with his finger at the level of the internal opening of the cervix.

Why can we resort to detaching membranes?

The purpose of detaching the membranes is to induce childbirth. This is why the reasons can be multiple. First of all, the term is over but the baby is healthy and there is no life-saving urgency to induce childbirth. " There may also be a need to organize the birth because the infant or the mother needs special care », Illustrates Dr Massardier. Finally, some pregnant women ask their doctor or midwife for a so-called convenient induction, without medical reason, which can then only be considered from 39 weeks of amenorrhea. In this case, the cervix should be favorable, the due date known, and the uterus should not be scarred. But not all doctors or midwives agree to perform such a gesture without medical reason.

A painful technique?

To detach the membranes, the gynecologist or midwife will perform a vaginal examination. The practitioner crosses the cervix and then makes small circular movements with his index finger once it has reached the internal opening of the cervix to loosen the membranes of the amniotic sac. " At the very least, this gesture is unpleasant, and it can potentially be painful since two tissues are detached. This is why the patient is always warned before the procedure is performed », Continues the doctor. In addition, the principle is to induce contractions to trigger childbirth and these are necessarily accompanied by pain. Finally, usually, bleeding may occur.

Detachment of membranes, an effective technique?

Detachment of membranes is a technique identified by the HAS in its recommendations for induction of labor dating from 2008. The national college of French Obstetrician Gynecologists also recognizes this technique in its recommendations on prolonged pregnancies in 2011. " According to the various studies, we are not very sure that this technique is entirely effective compared to a drug trigger, but it remains a method sufficiently recognized to say that it can have beneficial effects. The problem is, it doesn’t work immediately, which is why it isn’t used if labor needs to be induced urgently », Reports Dr Massardier.

A method that involves risks?

Like any exam or technique, there are always risks, even if they are truly exceptional. " When the placenta is too low, it can cause heavy bleeding. But this technique is just not practiced in this case », Emphasizes the obstetrician-gynecologist. Of course, the technique can make the patient lose water, but this is not considered a risk since the objective is precisely to help her give birth more quickly. And we know that opening the water bag speeds up work. Detachment of the membranes does not require the mother to be hospitalized in the maternity ward for monitoring either.

Are there any contraindications to membrane detachment?

As seen above, the technique should not be performed if the placenta is poorly positioned, especially in the case of placenta previa. " But this is something that is normally seen on ultrasound ”Says Dr. Massardier. In contrast, women who have had a Caesarean section in a previous delivery, and who have the green light to attempt a low route for a new birth, may benefit from a detached membrane.

An outdated technique?

Despite its limitations, the technique of separating membranes remains widely practiced. " It should be seen as a back-up technique that borders on convenience. But if it doesn't work, the practitioner will not peel off the membranes for several days in a row. If childbirth must be started quickly, medication techniques are preferred », Recalls the doctor.

It should be noted that another manual technique has recently been developed, based on principles close to the separation of membranes. It is a balloon that is slipped into the cervix and inflated. " The volume is therefore more important than the fingers but the principle is the same: we hope that by stimulating the cervix, we will allow the secreting of prostaglandin molecules which have an effect on the maturation of the cervix and the initiation of contractions. The philosophy of this mechanical system is therefore the same as for the separation of membranes, but the efficiency is more important ”Says Dr. Massardier.