Belly Up

* bellies * birth * babies * breastfeeding *

Wednesday, November 9, 2011

Stripping, Stretching, Sweeping-You Want to do What?

Ready to be swept?
Sweeping, stretching and stripping all sound a bit scary, after all one's lower uterus is not used to getting much action. So what is all this stretching stuff?  Sweeping of the membranes, also called stripping or stretching the membranes, is a procedure performed during a vaginal exam.  A finger is placed into the cervix,  then in technical terms, "the inferior pole of the membranes is detached from the lower uterine segment by a circular movement of the examining finger".* In lay terms that means that a finger is placed through the cervix and separates the membranes of the amniotic sac from the bottom part of the uterus, lifts it up a bit and a finger is run around the exposed diameter.  The agitation of this area and manipulation of the membranes may cause the body to increase production of  prostaglandins, ie the hormones that are thought to ripen the cervix in preparation for labor.

It is this prospect that the stripping will lead to spontaneous labor either in the short or long term that makes this procedure attractive.  Studies do show that having the membranes swept can create clinically significant results.  If done at each appointment from 38 weeks on, membrane sweeping was shown to slightly reduce the number of pregnancies that go past 41 and 42 weeks.  However as most pregnancies will not go past 42 weeks anyway this information has limited significance for the average expectant woman but is useful for a woman with a history of post dates pregnancies (postdates meaning past 42 weeks, not past EDD).  The studies also showed that membrane sweeping did somewhat reduce the need for other means of induction such as the use of prostaglandins or oxytocin/pitocin.  What the studies don't say is why those inductions were needed.  If they were needed because the pregnancy had a medical need to end and this procedure helped end those pregnancies safely with less intervention- then this is great news.  However if it means we have found yet another way to end a thriving pregnancy- that really isn't great news at all.
This kind of sweeping might
help you get ready
for labor too
Membrane sweeping may not seem like a big deal as many providers do routine vaginal exams the last weeks of pregnancy anyway (see my post on routine vaginal exams) so a more vigorous exam doesn't seem like a big step to take, but it is invasive and it is an intervention.  The sweeping is usually uncomfortable for mom as it is basically a vaginal exam on steroids and often produces light bleeding or spotting afterwards.  Membrane sweeping can lead to irregular, uncomfortable but ultimately unproductive contractions that are only capable of disrupting mom's prospects of a good night's sleep...but not actual labor.  At worst the procedure can cause the baby's amniotic sac to rupture which can mean a premature baby if the stripping was done shy of term or lead to an unnecessary induction and/or c-section. The risk is also higher that GBS will be passed on to the baby when membrane stripping is done on women who are GBS positive.

Not wanting to dwell on the negative, membrane sweeping is one of the evidenced based methods that can sometimes stimulate labor without the use of other more invasive or higher risk means such as cytotec or pitocin and sometimes inductions really are indicated or desired.  The membrane sweeping can create a situation where the body is tricked, so to speak, into producing more of its own hormones in hopes of avoiding the use of other synthetic hormones.  Another huge bonus is that it can be done out side of the hospital so that mom can be at liberty until she reaches a point where she is having contractions, be it that night or in 4 weeks, that deem it time to go elsewhere.  It needs to be kept in mind though that membrane sweeping is not a sure thing. It seems to be one of those things that works when one's body is ready and doesn't if it is not.

Both midwives and OBs use this procedure, though obviously some more than others and often under different circumstances.  Some careproviders do routine membrane stripping starting at 37 weeks, some suggest it only when a mom has a prior history of a post dates pregnancy or if there is concern over the baby's size (though fetal measurement is hardly an accurate science) and some will only use it when there is a need to encourage the pregnancy to end for either the health of mom or baby.  However it is very uncool for a careprovider to strip a woman's membranes without obtaining consent.  If you are pregnant and membrane stripping comes up, it is wise to find out why your provider is recommending this procedure.  A healthy pregnancy will end when baby and mom are ready so if a careprovider routinely does membrane stripping he may have a more medical or highly managed philosophy of birth and this intervention is then likely to be the first of many.  Membrane sweeping may also inadvertently undermine a woman's trust that her body will know when to birth.  On the other hand, if the pregnancy needs to end, membrane stripping is a great option to try before advancing to other more invasive and higher risk methods.