When you become pregnant, your body will begin to develop the placenta—the organ that will provide oxygen and nutrition to your baby from within the uterus. The placenta typically attaches to the top or side of the uterine wall. However, in some pregnancies the placenta attaches lower in the uterus and can cause a condition known as placenta previa.
What Is Placenta Previa?
Placenta previa happens when the placenta lies low in the uterus and either partially, or completely, covers the cervix. This positioning ends up blocking baby’s exit route, causing potential problems as your pregnancy progresses—especially during labor and delivery.
Placenta previa affects roughly 1 in 200 women in the third trimester of pregnancy. Who’s at risk for placenta previa? People who:
- Have had more than one child
- Had previous c-section births
- Have caring on the uterus from a previous surgery
- Are carrying more than one baby
- Are age 35 or older
- Smoke cigarettes or use cocaine
There are a few different ways to classify placenta previa, depending on how much of the cervix is covered:
- Complete previa: the cervical opening is completely covered
- Partial previa: a portion of the cervical opening is covered
- Marginal previa: the placenta extends just to the edge of the cervix
While those with placenta previa are considered to have a high-risk pregnancy, your care team will keep a close eye on your pregnancy and baby to ensure a healthy pregnancy and delivery for both mama and baby.
How Will I Know If I Have Placenta Previa?
While some mothers-to-be have no symptoms at all, the most common sign that you may have placenta previa is painless bleeding in the second half of pregnancy. If you have vaginal bleeding at any point during your pregnancy, it’s important to call your provider right away. If your bleeding is severe, go directly to the hospital for immediate care.
Placenta previa is something that will be assessed during your routine 20-week anatomy ultrasound appointment. So even if you haven’t had any symptoms indicating placenta previa, your provider will be able to tell you if you’re in the clear or not.
How Is Placenta Previa Treated?
In all cases of placenta previa, your medical care team will keep a close eye on your pregnancy using ultrasounds to see if the previa resolves as your belly grows. Sometimes the distance between the cervix and placenta grow as your uterus grows, which might help your placenta previa resolve on its own. The more the covered your cervix is, and the later in your pregnancy it remains there, the less likely it is to resolve.
For some mamas, placenta previa may require bed rest, avoiding intercourse, restricting exercise, and limiting other activities that can increase your risk of bleeding. Depending on your little one’s gestational age, your provider may recommend steroid shots to help speed up the development of your baby’s lungs and other organs. If your bleeding becomes too intense, you may be admitted to the hospital to receive blood transfusions, or even need an immediate C-section.
What Are the Risks of Placenta Previa?
The biggest risk for those with placenta previa occurs later in pregnancy—typically during labor. When your cervix begins to dilate and efface in preparation for baby’s delivery, the blood vessels that connect the placenta to the uterus are at risk for tearing. This can cause severe bleeding, which can be harmful for both the pregnant person and their baby. Your provider will likely recommend a C-section delivery—sometimes prior to 40 weeks—to keep you and your little one as safe as possible.
If you’re diagnosed with placenta previa, it can be shocking and frustrating to learn your pregnancy and delivery may not go as planned. And we totally get that, mama. There are support groups for people on bed rest, as well as for other moms dealing with unexpected complications during pregnancy. Remember you’re not alone, and you’re in great hands. Your medical team will do everything they can to ensure you and your baby will be as healthy as possible during your pregnancy and delivery.