You go to your 20-week anatomy scan and find out that your placenta is low lying or covering the cervix, known as placenta previa.
Or perhaps you skipped the 20-week scan and instead found out about your previa because of third trimester bleeding.
Either way, you’re disappointed and possibly scared.
What does this mean for you and your baby? And what does it mean for your natural birth plan?
We’ll answer those questions and more in this post.
What Is Placenta Previa?
Typically the placenta (the organ that nourishes your baby during gestation) attaches to the upper part of the uterus. Placenta previa is a condition where the placenta is very low lying and/or covering all or part of the cervix. It affects 1 in 200 pregnancies by the third trimester. There are a few different kinds of previa:
- Total or complete previa – The placenta is covering the entire cervix.
- Marginal previa – The placenta is on the border of the cervix.
- Low-lying placenta – The placenta is within 2cm of the cervix but not bordering it.
What’s the big deal?
If you have placenta previa and the placenta is blocking your cervix, there’s no way for the baby to get out. Even if it’s only partly blocking or low lying, dilation may cause profuse bleeding which could cause death or require a blood transfusion. Additionally, placenta previa may cause:
- Slow fetal growth due to insufficient blood supply
- Fetal anemia
- Fetal distress due to low oxygen supply
- Infection and formation of blood clots
Can I Prevent Placenta Previa?
There’s not much you can do to prevent placenta previa, though there are risk factors that you may or may not have any control over. These include:
- Carrying multiples
- Having previously had a c-section
- Having had surgery on the uterus (fibroid removal, dilation and curettage (D&C), abortion, etc.)
- Having a short interpregnancy interval (the time between one pregnancy and the next)
- Being older than 35
- A previous condition of placenta previa
Diagnosis of Placenta Previa
Like placenta accreta, placenta previa doesn’t have many signs or symptoms. One most common sign is painless bleeding in the third trimester.
Other signs include:
- Pre-term contractions
- A transverse or breech baby
- Fundal measurements larger than expected
Diagnosis is often made from an ultrasound ordered after third trimester bleeding, or during the 20-week anatomy scan. However, as much as 90% of placentas seen as low-lying in the 20-week scan are no longer an issue in the third trimester. Because diagnosing a previa at that time is inaccurate at best, some mamas prefer to wait until closer to the third trimester for an ultrasound if they’re at all concerned about previa.
Treatment for Placenta Previa
When the placenta is low lying, like with a previa, there is increased risk of bleeding. This happens because the placenta is attached near or on the cervix which, when it dilates, can cause separation of the placenta from the uterus.
Treatment is bedrest and pelvic rest to reduce the risk of placental separation until as close to the due date as is safe. For many experiencing placenta previa, an early c-section may be necessary to avoid going into labor on your own.
What are my Birth Options with Placenta Previa?
With a marginal previa, where the placenta is near but not covering the cervix, you may be able to have a vaginal delivery. Many doctors will feel most comfortable if the placenta is 2cm away from the cervix, but talk with your doctor since each case is different. One study found that at least 60% of low-lying placenta cases ended with successful vaginal delivery. Your doctor will take into account whether there is also a placenta accreta present, which would likely mean a c-section is the safest route.
What’s a Natural Mama to Do?
If you have gotten a placenta previa diagnosis at your 20-week ultrasound, you will likely have nothing to worry about by delivery. Most placentas “move” higher in the uterus as the uterus grows so aren’t a problem by delivery.
If you are in your third trimester and your practitioner is still concerned about the placement of your placenta, you still have some options. As mentioned earlier, if your placenta is far enough away from the cervix, many doctors will be comfortable with a vaginal delivery (though they may ask you to labor in an operating room as a precaution). Ask for a second opinion if your doctor’s approach isn’t feeling right to you.
If you have a complete placenta previa, especially if an accreta is present, you likely need a c-section. This can be very disappointing for a natural mama. Just remember that your desire for a natural birth was so that you and your baby would have the safest birth experience. If a cesarean birth is medically needed to reach that goal, you are still a rockstar natural mama! Prepare for a gentle cesarean so that you and baby will have many of the health benefits of natural birth.
How About You?
What was your experience like with placenta previa? How did it affect your birth outcome?