Third trimester bleeding: The symptoms and causes

by motherandbaby |
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Any kind of bleeding during pregnancy can be scary, but what if it happens in those later months?

Bleeding in late pregnancy in your third trimester affects about 1 in ten mums-to-be. Less common than in the first trimester, it’s not always indicative of a serious problem, but you should tell your doctor or midwife right away to get checked out and find out what’s going on. Why you might be bleeding:

1. Changes in the cervix

During pregnancy, the cells of your cervix can change and it can soften, which can make it more likely to bleed, particularly after sex. This is called cervical ectropion and it’s harmless.

‘Or it could also be a harmless growth called a polyp, which can cause bleeding at any point in pregnancy,’ says GP Dr Philippa Kaye.

2. Vaginal infections

Thanks to your surge in pregnancy hormones, you’re more likely to get a vaginal infection. The most common one in pregnancy is thrush, which is a yeast infection and is treated with antifungal medication that poses no problems for your baby.

‘Bleeding can also be caused by an STI such as gonorrhea or chlamydia,’ says Philippa. ‘These can be treated with pregnancy-safe antibiotics.’

3. A ‘show’

A ‘show’ in late pregnancy is a small amount of blood mixed with mucus, a sign that plug sealing your cervix is coming away. It’s usually a sign that labour is about to begin, and can happen a few days before contractions start or during labour itself.

4. Placental abruption

This is when the placenta comes away from the wall of the uterus and it can cause bleeding. If this happens near the end of your pregnancy your baby may be delivered early. But it’s quite rare, only occurring in around one in 50 pregnancies.

5. Placenta praevia

Placenta praevia or a ‘low-lying placenta’ is when your placenta is sitting at the bottom of the womb near the cervix. Sometimes it blocks the cervix – and your baby’s way out – completely.

This is common in early pregnancy, and it usually moves out of the way as the pregnancy progresses. If it is still lying low after 20 weeks, it’s placenta praevia.

‘The bleeding relating to placenta praevia is generally painless,’ says Dr. Kaye. You could bleed very heavily during pregnancy or during the birth if you have placenta praevia, and if that’s the case, emergency treatment is available. Your hospital team may also recommend a cesarean if the placenta doesn’t move away from the cervix to let your baby pass.

6. Vasa praevia

Vasa praevia happens when foetal blood vessels run through membranes covering the cervix. When labour begins and your cervix dilates the vessels can break and this causes heavy vaginal bleeding.

It can be spotted before birth on an ultrasound scan, and the baby survival rate is 100 percent when it’s spotted before birth.

‘All women who have booked for antenatal care with a hospital will have a phone number to ring to discuss any worries,’ says Dr. Kaye, ‘However if you’re bleeding heavily or in severe pain, call 999.’

If you do find you’re bleeding in late pregnancy, your doctor or midwife will examine you and ask about any other symptoms you’re having.

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