Usually, once an egg has been fertilized, it remains in the fallopian tube for around 12-24 hours before being gently swept (by hair-like follicles) towards the uterus. Once landing in the uterus, the fertilised egg will remain housed there until labour and birth.
If the fertilised egg does not travel all the way to the uterus, this is known as an ectopic pregnancy and causes complications. By far, the most common place an ectopic pregnancy occurs is in the fallopian tube, which happens in approximately 95% of cases. Other (uncommon) sites an ectopic pregnancy can occur are the entrance to the uterus (2.5%) and the remainder are in the ovary, cervix and abdominal cavity. There is one reported case of a 32-week-old baby surviving just outside of the uterus!
The causes vary from woman to woman and each individual pregnancy, but sometimes it’s completely unknown or unexplained. Some of the most common causes are thought to be:
Pelvic inflammatory disease (PID) can increase the risk of ectopic pregnancy, as can inflammation from any infection. Preventing infections in general could help to reduce the risk of ectopic pregnancy too. Pain during sex, bleeding between periods or abnormal vaginal loss can indicate infection (and other abnormalities) so ensure you investigate these symptoms.
It’s extremely rare for an embryo to survive outside the uterus. If an ectopic pregnancy occurs, medical intervention almost always means the pregnancy will need to end. If the embryo were left to grow, it would be life threatening to the mother and the embryo/foetus would not survive in most cases. That said, in medicine you never say always and you never say never.
Signs and symptoms of an ectopic pregnancy
Like with all pregnancies, at first there could be no signs or symptoms, therefore the ectopic pregnancy can go unnoticed. Or it could appear to be a normal pregnancy until around four weeks (sometimes later), when pain and/or vaginal bleeding tend to be present. Although less common, an ectopic pregnancy (especially when pregnancy hasn’t been noticed or confirmed) could continue up until to week 12.
The longer the ectopic pregnancy goes on for, the more serious the impact for mum, especially if the fallopian tube ruptures.
Symptoms can include:
Effects on mum
If an ectopic pregnancy has started to develop there could be a ‘rupture’ in the area in which the embryo is growing due to lack of space.
If diagnosed and treated early the outcome is often very positive for mums. In some cases there can be permanent damage – most commonly to the fallopian tube.
Looking after yourself if you’ve had an ectopic pregnancy
Marie Louise is an experienced Midwife, PTLLS adult educator and hypno-birthing teacher from the UK. She has travelled extensively to learn about midwifery in different cultures and has also practised in Australia. She runs ‘Modern Midwives Meetups’ which provide a safe space for midwives to share best practice and hear from experts in the maternity field. Marie Louise is a sought after expert and has most recently been invited to Parliament to discuss maternal mental health and maternity discrimination. She's also a communications partner for Child.Org, an equal opportunities charity for children and advises Cocoon Family Health, a perinatal mental health charity based in London.