What is Placenta Previa?

The placenta is an organ that grows specifically to facilitate this pregnancy, and is attached to the uterine wall. It provides hormones and nutrients to the baby, and is connected to the baby by the umbilical cord. As pregnancy progress, the uterus grows and stretches and this moves the placenta away from the cervix. If this does not happen, the placenta may remain near to or covering the cervix. This condition is known as placenta previa.

The exact causes of placenta previa are unknown. However, the risk of developing placenta previa is slightly greater for women:

  • aged 35 or over
  • who have experienced previous placenta previa
  • who have had previous caesarean births
  • who are carrying twins or more
  • who smoke
  • who use cocaine
  • who have suffered miscarriages in the past

How is placenta previa diagnosed?

The location of the placenta will also be noted during your 18-21 week scan. If the sonographer thinks your placenta is low-lying, you will be offered a second scan later in the pregnancy. This will typically happen at around week 32. At this second scan, around 90% of women will discover that the placenta has moved to where it should be.

If your placenta is still low lying at the second scan, you will be monitored by your healthcare provider until the birth, or until the placenta moves. You may be:

  • put on bed rest
  • put on pelvic rest (this means no sex, no orgasms and no vaginal exams)
  • admitted to hospital for the last few weeks of the pregnancy
  • Advised to take it easy (no heavy lifting or activities that may put you under unnecessary strain)

Your treatment will depend upon the severity of your condition. There are three different diagnoses:

  • Low-lying placenta – the placenta is close to, but not covering, the cervix
  • Partial placenta previa – part of the cervix is covered by the placenta
  • Total placenta previa – in this instance, the entire cervix is obstructed by the cervix

The risks associated with this condition include bleeding, reduced fetal growth and separation of the placenta from the uterine wall. Your healthcare provider will assess your risk factors and advise on the best course of treatment.

Will I be able to have a normal birth?

If the placenta is near or covering the cervix at the time of the birth, you will be unable to have a vaginal delivery. You will instead deliver by caesarean surgery. Placenta previa is a rare condition which is only present in 0.5% of births.

You should contact your healthcare provider immediately if you experience vaginal bleeding.

This information is not intended to replace the advice of a trained medical doctor. Health & Parenting Ltd disclaims any liability for the decisions you make based on this information, which is provided to you on a general information basis only and not as a substitute for personalized medical advice. All contents copyright © Health & Parenting Ltd 2018. All rights reserved.