by Teresa J. Mitchell
Your placenta's been hard at work during your pregnancy transporting oxygen and nutrients from your blood to your baby's umbilical cord. This pancake-shaped organ usually is located high in your uterus, near where your baby first entered the womb via a fallopian tube.
What's normal: During birth, your baby heads through the cervix and down the birth canal. Within a half hour of birth, the placenta separates from the uterine wall and leaves the uterus. This order is necessary because your baby depends on the placenta to provide life-sustaining oxygen during birth.
What's abnormal: If the placenta implants lower in your womb, it can grow over the cervix and partially or totally block your baby's path into the birth canal, causing bleeding and making a birth by cesarean necessary. A vaginal delivery could cause severe bleeding and death for the mom and severe oxygen-deprivation and death for the baby.
This condition affects about 1 in 200 pregnant women during the third trimester. It's more common in women who:
- Have several children
- Are 35 or older
- Are Asian
- Have had uterine surgery
- Have had a prior birth by cesarean
- Are carrying twins, triplets or other multiples
- Conceived through IVF
Typically, it can't be prevented, but you can lower your risk by quitting, if you smoke.
Types of Placenta Previa
Complete:The entire cervical opening is completely covered.
Partial: Part of the cervix is covered by the placenta.
Marginal: extends just to the edge of the cervix.
Your 18-20 week ultrasound result is often your first hint that you have a low-laying placenta. The ultrasound will be repeated during the third trimester. Most low-lying placentas move up and out of the way as the uterus grows. If the placenta still covers the cervix during the third trimester ultrasound, the condition will probably not resolve on its own.
Painless bleeding that starts near the end of the second trimester or the beginning of the third trimester can indicate the condition. The bleeding can be severe. It might stop on its own, but could start again a few days or weeks later. An ultrasound examination will confirm the diagnosis.
Hemorrhage: This condition heightens the risk of hemorrhage that threatens you and your baby's life. As your cervix thins out and opens preparing for birth, the placenta's attachments to the uterus can be damaged. If this happens, you can begin bleeding.
Preterm birth: Bleeding can increase the risk for premature rupture of the membranes, leading to premature labor. Also heavy bleeding might make an early emergency cesarean necessary.
Emotional effects: As with other complications of pregnancy, this condition can affect a your emotional well-being.
Bleeding after delivery: The upper part of the uterus contracts most effectively. When the placenta implants in the lower part, contractions after birth aren't as effective at stopping bleeding.
Women with this complication also have placenta accreta. This is when the placenta is implanted too deeply and doesn't detach as well. A prior cesarean increases your risk of placenta accreta.
Most women with this complication in developed countries will delivery healthy babies. The maternal mortality rate is less than one percent. The risks for mothers and babies in countries without medical resources increases.
Treatment is determined by the length of your pregnancy and whether the placenta has begun detaching and the health of your baby. The goals are to prevent bleeding and to lessen the risk of a preterm baby. You'll probably receive several ultrasounds, each of which bring you an opportunity to see your baby.
Diagnosed, but no bleeding: If placental previa has been diagnosed but you're not experiencing bleeding, your doctor will probably suggest bed rest or that you limit your activities to lessen the danger of bleeding until your baby's big enough to arrive safely by cesarean. Sex can trigger vaginal bleeding and is off limits. You'll probably be asked to not exercise and to be prepared to immediately get emergency care if you begin to bleed.
Start to bleed: If you start to bleed, you'll probably be admitted to the hospital and watched closely. Cesarean delivers are almost always necessary. The placenta can be torn from its roots during a vaginal delivery, causing life-threatening bleeding for mom and a lack of oxygen for the baby.
Uncontrolled bleeding: If your bleeding won't stop or your baby is in distress, you might need an emergency cesarean, even if the baby is premature.
The outlooks sounds gloomy, but most moms diagnosed with placenta previa have successful pregnancies and come home with a healthy baby.
Have you experienced this condition? How did you make it through? What helped you?