An amniotomy is when a small hook is used to rupture your amniotic sac (break your water) and it's done frequently on laboring women. From my course manual with my own notes, an amniotomy is done to:
* To induce or augment labor.
* To check for meconium (baby's first stool).
* To place the internal fetal monitor the infant’s scalp. (OUCH! They actually screw a little wire probe into the baby's scalp to get a reading if they aren't happy with the external fetal monitoring.)
* The amniotic sac is designed to act as a cushion for the baby's head during labor. The increased pressure around the fetal head may lead to deformities of the skull.
* The reduction in the amount of amniotic fluid may increase compression of the umbilical
cord which would show as fetal distress during labor, baby's not getting enough oxygen.
* Increases the possibility of a cord prolapse, when the umbilical cord comes out through the cervix. This generally necessitates a stat c-section as it can be life threatening to the baby. If the baby's head is not fully engaged in the pelvis and your amniotic sac is broken the cord can prolapse and the infant's head can then drop and compress the cord, cutting off oxygen to the baby.
* Having your water broken increases the likelihood of infection from vaginal exams and probes placed into the vagina. (Still need to find study that showed infection risk increases not 24 hours after your water breaks, but 24 hours after your first vaginal exam after your water breaks.) It's when people start sticking things in there that you introduce the increased risk of infection! The amniotic sac is protecting the baby from outside bacteria.
* Some practitioners will start the cesarean clock once the amniotomy is performed, some say 24 hours after water breaks it's c-section time. I've heard even shorter time frames, too, but again - the risk isn't your water breaking, the risk is vaginal exams after your water breaks.
* This may cause your practitioner to restrict you to bed.
* This may cause the practitioner to restrict your use of the tub or bath. (To which I say, show me the study that says my risk of infection is increased using a tub after my water breaks and I'll show you a study that says you sticking your hand up my vagina increases my risk of infection.* OH, sorry, tired and snarky today. I wouldn't really say that to my care provider because she's the one that lets me labor in the tub anyhoo.)
And not listed in this text but I also read that breaking your water prematurely makes it harder for the baby to move around and get into a better laboring position. If there is still water the baby will shift even in labor and move about to get into an optimal position (ideally - sometimes those sweet little things don't want to cooperate and come up with all sorts of acrobatic antics in there.) Letting your water break on its own instead of popping it prematurely gives your baby time to do their little labor dance, but once your water breaks the baby loses their mobility aid and they are more stuck.
In my personal experience, I delivered one baby "in the caul" when the sac was emerging unbroken around the baby. The cushion that it provided made for a more gentle arrival - I could feel the difference between my labor with the water sack in tact and my births when my water broke.
There are situations in which an amniotomy is recommended, but that's up to you and your care provider to determine. It's good to know that there ARE risk associated with the procedure, it does not necessarily speed things along, and it does start the timer for how long you can labor before the pressure increases for a c-section.
And if your water breaks on its own before active labor begins (which it does in about 10 to 15% of births depending on which website you read) then there's nothing you can do about that except minimize vaginal exams (YES, you can just say no to vaginal exams!) Laboring without your water in tact will still be okay! 🙂
*I cannot get the full study online but here explains more:
Although many questions regarding ruptured membranes, vaginal examinations and infection risk remain unanswered, one concept is clearly identified: avoid vaginal examinations whenever possible.
If you have medical journal access, here's the full info: Seaward, P. G., Hannah, M. E., Myhr, T. L., Farine, D., Ohlsson, A., Wang, E. E., et al. (1997). International multicentre term prelabor rupture of membranes study: Evaluation of predictors of clinical chorioamnionitis and postpartum fever in patients with prelabor rupture of membranes at term. Am J Obstet Gynecol, 177(5), 1024-1029.