Placental abruption: symptoms, causes and treatment

The NHS lists stomach pain, vaginal bleeding and frequent contractions. Tommy's says that most people with placental abruption have vaginal bleeding, but not everyone does, so symptoms without bleeding still need medical attention. The pain varies: some feel as if their tummy is bruised, while others describe it as very severe.

Tommy's explains that in a concealed abruption the blood collects behind the placenta, so there may be no bleeding from the vagina but there may be lower back pain. Some people have frequent contractions that do not stop, or a bump that feels tense or hard. A small number have no symptoms at all. It is more likely in the second half of pregnancy, but help should be sought at any stage.

• Vaginal bleeding, light or heavy.

• Stomach pain or cramping that does not settle.

• Frequent contractions or a tense, hard bump.

• Lower back pain, which Tommy's links with a concealed abruption.

Contact your maternity unit straight away if you have any of the symptoms above, or NHS 111 if you cannot reach them. Tommy's says to call 999 straight away if you have a lot of pain and/or bleeding.

Tommy's also advises getting checked after any injury to your tummy, such as a fall or car accident, even if there is no bleeding or visible bruising. Symptoms without bleeding still need medical attention.

The placenta is the organ that attaches to the womb lining during pregnancy, passing oxygen and nutrients from your blood to your baby through the umbilical cord. In placental abruption it starts to come away from the wall of the womb. Tommy's, the pregnancy charity, says the more of the placenta that separates, the more serious the abruption is, and the further along pregnancy it happens, the better the baby's chance of survival.

The NHS describes it as a serious condition that is not common. It can affect the baby, increasing the risk of premature birth, growth problems and stillbirth. NHS inform in Scotland says it is more likely later in pregnancy and can be life-threatening for the mother and baby, which is why emergency care is the standard response.

The NHS says it is not clear what causes placental abruption, and Tommy's agrees that doctors do not always know exactly why it happens. Risk factors are better understood than causes. The NHS lists injury to the abdominal area, smoking, cocaine use and high blood pressure.

Tommy's separates the evidence by strength. It says smoking can double the risk. Injury such as a car accident, a serious fall or domestic violence can increase it, with no need for visible bleeding or bruising before seeking advice. It describes the links as strong for chronic high blood pressure, pre-eclampsia, cocaine use, intrauterine infection, a uterine abnormality, a previous abruption and too little amniotic fluid. Weaker evidence is cited for a previous caesarean, waters breaking early, not being a first pregnancy, being over 40 and carrying more than one baby.

Tommy's says that a healthcare professional will ask about symptoms, risk factors and pregnancy history, will carry out an internal examination, and will monitor the baby's heart rate. An ultrasound may also be used.

Treatment depends on how many weeks pregnant you are, how well you and your baby are, and how severe the abruption is. The NHS says that near the due date the baby will need to be born straight away and a caesarean may be recommended, whereas a very premature baby with a minor abruption may be kept in hospital for close observation.

Tommy's describes the same logic in more detail. After 34 weeks you may be advised to give birth straight away, and vaginal birth may be possible if you and your baby are well and labour is progressing. Before 34 weeks, with a small abruption and both of you well, monitoring may include scans and fetal heart rate checks, often in hospital, with birth recommended by 37 to 38 weeks to reduce stillbirth risk. If either of you becomes very unwell, an emergency caesarean may be needed. Tommy's says heavy blood loss in labour is treated with oxygen and a blood transfusion.

Tommy's says nothing can guarantee that an abruption will not happen, but you can reduce some risks: attend all antenatal appointments, avoid intensive or high-impact sport, stop smoking with support, avoid recreational drugs, particularly cocaine, and seek help if you are experiencing domestic abuse.

If you have had an abruption before, Tommy's says you are more likely to have another, but the risk remains low: out of 100 people who have had one, around 3 to 4 will have another. Midwives and doctors are likely to monitor later pregnancies very carefully.

Placental abruption is an emergency managed by NHS maternity and obstetric teams, usually through the maternity unit or A&E, and the NHS says treatment depends on how many weeks pregnant you are and how you and your baby are. If you have had one before, later pregnancies are monitored very carefully through the NHS maternity pathway. Private maternity care follows the same emergency principles, and anyone with symptoms should go to a maternity unit or A&E rather than waiting for a routine appointment.