Bleeding during pregnancy
Bleeding during pregnancy is relatively common, especially during the first trimester. Although light bleeding or spotting is not usually a cause for concern, vaginal bleeding in pregnancy may be a sign of something more serious and medical advice should be sought.
Contact your midwife or GP immediately to make sure you and your baby are healthy.
Your doctor or midwife may suggest you go to an early pregnancy assessment unit (EPAU) in hospital. Staff there may test your blood or urine to check pregnancy hormone levels, examine your cervix, check the baby’s heartbeat by Doppler ultrasound or arrange an ultrasound scan.
Bleeding in the first trimester
About a quarter of women have some bleeding during the first 12 weeks (first trimester) of pregnancy. Possible causes of first trimester bleeding include:
Implantation bleeding. You may experience some normal spotting within the first six to 12 days after you conceive as the fertilised egg implants itself in the lining of the uterus. Some women don't realise they are pregnant because they mistake this bleeding for a light period. Usually the bleeding is very light and lasts from a few hours to a few days.
Miscarriage. Because threatened miscarriage that may lead to early pregnancy loss is most common during the first 12 weeks of pregnancy, it tends to be one of the main concerns with first trimester bleeding. But that doesn't necessarily mean that if you're bleeding you've lost the baby, especially if you don't have any other symptoms.
Ectopic pregnancy. In an ectopic pregnancy, the fertilised embryo implants outside the uterus, usually in the fallopian tube. If the embryo keeps growing, it can cause the fallopian tube to burst, which can be life-threatening to the woman. Although ectopic pregnancy is potentially dangerous, it only occurs in about 1% of pregnancies.
Other symptoms of ectopic pregnancy are strong cramps or pain in the lower abdomen, usually on one side, pain on passing urine or stool (poo), and light-headedness.
Molar pregnancy (also called gestational trophoblastic disease). This is a very rare condition in which abnormal tissue grows inside the uterus instead of a baby. In rare cases, the tissue is cancerous and can spread to other parts of the body.
Other symptoms of molar pregnancy are severe nausea and vomiting and rapid enlargement of the uterus.
Additional causes of bleeding in early pregnancy include:
Cervical changes. During pregnancy, extra blood flows to the cervix. Intercourse or a cervical screening test, which cause contact with the cervix, can trigger bleeding. This type of bleeding isn't cause for concern but it’s important to seek medical advice to rule out any other problems.
Infection. Any infection of the cervix, vagina or a sexually transmitted infection (such as chlamydia, gonorrhoea or herpes) can cause bleeding in the first trimester.