Placenta Previa Questions Answered
Placenta previa literally means afterbirth first. It is a condition in which the placenta – the flapjack-shaped organ that supplies the fetus with nutrients through the umbilical cord – implants itself unusually low in the uterus, next to or covering your cervix.
If the placenta completely covers the cervical opening it is known as a complete or total placenta previa. If it only partially covers the opening, it is known as a partial placenta previa. If it is within two centimeters of the cervix but not covering it, the condition is known as a marginal placenta previa.
What causes this condition?
Placenta previa happens when an embryo implants itself in the lower uterus. Then, when the placenta grows, it may partially or completely cover the cervical opening.
Is placenta previa serious?
Placenta previa discovered early in pregnancy is not yet cause for alarm. More often than not, the placenta will fix itself, “migrating” away from the cervix. In actuality, the placenta is attached to the uterus and does not move. But as the uterus grows, the placenta may end up farther from your cervix. In addition, the placenta itself has a general tendency to grow toward the richer blood supply at the top of the uterus.
In fact, only about 10% of women diagnosed with placenta previa at mid-pregnancy still have it when their time comes to deliver. Unfortunately, a total placenta previa is less likely to resolve itself than a marginal or low-lying placenta.
What if the condition persists?
Even if you have placenta previa later in pregnancy, it may still move away from the cervical opening. You will need to have a follow-up ultrasound early in your third trimester to check on the condition of the placenta. You may need an examination sooner if you experience any vaginal bleeding.
If your placenta previa persists, you will need to be very careful. You should have regular ultrasounds and be wary of vaginal bleeding. Your doctor will tell you to avoid strenuous activities, heavy lifting, and sex for the rest of your pregnancy.
Bleeding from placenta previa can range from spotting to extremely heavy. This happens when the cervix begins to dilate. It is usually painless and starts without warning. Depending on the severity of the bleeding, you may need to deliver your baby immediately and may also need a blood transfusion.
If you begin bleeding or having contractions, you will have to be hospitalized. Depending on the amount of bleeding, the health of you and your baby, and how far along you are in your pregnancy, the baby may need to be delivered by c-section immediately.
If the bleeding stops and everything is ok, you will likely be sent home. But if the bleeding starts again, you will have to return to the hospital immediately.
What about the delivery?
If you still have placenta previa when you are ready to deliver, you will need to have a c-section. Unfortunately having placenta previa may increase your risk for other complications. For instance, you may be at risk of heavy bleeding during and after delivery. Once the baby is delivered the placenta will be delivered and you will be given medications that will cause your uterus to contract. This helps to stop the bleeding from the area of the uterus where the placenta was implanted.
Unfortunately, women who have placenta previa are also more likely to have placenta accrete, a condition where the placenta is implanted too deeply and does not separate easily at delivery. Although placenta accrete only occurs in about one out of 2,500 births overall, your chances of developing this problem are one out of ten if you still have placenta previa when the time comes to deliver. This may cause severe bleeding and a blood transfusion and hysterectomy may be necessary to stop the bleeding.
Who's at risk for placenta previa?
For most women, there are no apparent warning signs, but if any of the following risk factors apply to you, your chances may be increased.
- You've had placenta previa in an earlier pregnancy
- You've had previous c-sections
- You're having a multiple pregnancy
- You've had uterine surgery
- You are a cigarette smoker
- You use cocaine
As always, if you ever notice any bleeding or pains in your abdomen, call your doctor right away.