The words shoulder dystocia bring fear to the heart of every doctor and midwife. This means that the one, less frequently both, shoulder(s) of the baby are not entering the pelvis during the birth as they should. Shoulder dystocia occurs in less than 1% of all births according to some studies. This can lead to increased complications for the baby and the mother.
Warning Signs for Shoulder Dystocia
Contrary to popular belief there isn't one exact method to predict who will have a shoulder dystocia. Many different theories have been tested, each with varying results. We've looked at babies who are big, moms who are small, complicated pregnancies, particularly in regards to complications like gestational diabetes, inductions, gestational age, previous babies with shoulder dystocia, and many others. For example using the weight of the baby alone as a factor, nearly a quarter of the cases of shoulder dystocia happen to babies under the considered "danger weight." The best predictor may be a combination of the factors involved.
What do you do if you and your practitioner feel you're in danger of a shoulder dystocia? The answer isn't clear on all counts. We do know that certain positions are more likely to lead to shoulder dystocia, for example the lithotomy position (laying flat on your back) can prevent the sacrum from properly moving during birth and therefore narrowing the amount of room in your pelvis for the shoulders. Episiotomy, a surgical cut in the area of skin between the vagina and rectum, is often debated with one side saying that doing a generous episiotomy allows room for the practitioner to do maneuvers, the other side argues that the perineum is not what is holding the baby back and should be left intact. Nor is routine cesarean section or induction the answer for all.
Maneuvers to Help Alleviate the Dystocia
There are several things that can be done to help solve the problem of the shoulder dystocia. Since each birth is different not everyone of these will work every time, so multiple maneuvers are likely to be tried in very rapid succession to help resolve the situation in a positive manner. Here are some of the suggested techniques:
- Suprapubic Pressure: This pressure is at the pubic bone, not at the top of the uterus. This might allow the shoulder enough room to move under the pubis symphysis.
- Gaskin Maneuver: Get the woman into a hands and knees position. This will also change the diameters of her pelvis, though is not always possible with epidural anesthesia.
- McRobert's Maneuver: Flex the mother's legs toward her shoulders as she lays on her back, thus expanding the pelvic outlet. One study showed that this alleviated 42% of all cases of shoulder dystocia.
- Woods Maneuver: This is also known as the corkscrew, the attendant tries to turn the shoulder of the baby by placing fingers behind the shoulder and pushing in 180 degrees.
- Rubin Maneuver: Like the Woods maneuver, two fingers are placed behind the baby's shoulder, this time they are pushing in the directions of the baby's eyes, to line up the shoulders.
- Zavanelli Maneuver: Pushing the baby's head back inside the vagina and doing a cesarean. This is the mostly frequently asked about method, but also one of the most dangerous.
After the Birth
After a hectic birth that includes a shoulder dystocia, there may be additional things your doctor or midwife will want to watch for in you and your baby, including:
- A baby that is slow to start and may require assistance with breathing.
- Fractures of the baby's collar bone (clavicle) or humerus.
- Fetal Brachial Plexus injury.
- Repairs for episiotomy or tearing done during the birth.
- Maternal hemorrhage.
- Uterine rupture.
While a shoulder dystocia isn't a very common occurrence, knowing what potential risk factors are for you and your baby can help you make wise choices for your labor and birth.
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