Conditions that threaten women’s lives in childbirth & pregnancy

Pulmonary Embolism/blood clots

Blood clots in the legs or lungs are a leading cause of illness associated with pregnancy and birth and can be life-threatening (maternal morbidity). Thromboembolic events, when blood clots form in one of the blood vessels and break away, causing a blockage elsewhere, include deep vein thrombosis (DVT - a blood clot in a deep vein) and pulmonary embolism (PE- a blood clot in the main artery of the lung), see What is a life threatening condition in childbirth and pregnancy?’. All pregnant women are at risk of thrombosis (blood clots) during their pregnancy and until at least 6 weeks after the birth. Clinicians are often on the alert for clots in the first couple of weeks after birth, especially if the woman has had a caesarean section and therefore been unable to move around (which can increase the risk of thrombosis). The women we spoke to experienced their thromboembolic events at varying times during and after their pregnancies.
Symptoms & Diagnosis
When she was pregnant, Alison T went to hospital because she had pneumonia. Whilst there, the doctors discovered that she had multiple PEs in her chest. She was put on blood thinning drugs (known as anticoagulants) and very closely monitored for the rest of her pregnancy. Clare experienced an “intense throbbing pain” in her calf. Tests showed that she had developed DVT in her legs. Sophie developed a severe pain in her chest a couple of days after birth, which turned out to be a PE.
Cate felt the symptoms of her PE came on slowly over a couple of days. Her daughter was 3 ½ weeks old when she developed a pain in her shoulder. At first she thought it was a muscle strain, but the pain intensified. She went to hospital and was started on anti-coagulation drugs, as they thought she had a pulmonary embolism. Doctors were not able to scan her chest for a couple of days.
The principal treatment for thromboembolic conditions is anticoagulant drugs which prevent any blood clots that have formed from getting larger and stop new ones from forming. Warfarin is the usual anticoagulant drug given but it takes a few days for warfarin to work fully so heparin injections are used for immediate effect. The women we interviewed had been given two brands of heparin; Clexane (enoxaparin) and Fragmin (dalteparin).
Women may need to be on warfarin for several months until the clot has resolved. Although treatment will start off in hospital where the clot may be diagnosed by a scan, the ongoing treatment is often managed by the GP. Women may also be asked to wear compression stockings.
Alison T was diagnosed with multiple PEs in her chest while she was pregnant. Warfarin is contraindicated (should not be used), in pregnancy, so she so she had Fragmin (dalteparin) injections twice a day for the rest of her pregnancy and she was monitored very closely. Since she was not able to take warfarin she was fitted with a vena cava filter (a small medical device placed in the blood vessels) which provided added protection against the PE. After the baby was born she was prescribed warfarin.
Clare was given Clexane (enoxaparin) at first and then warfarin for her DVT which she took for 4 ½ months. She also needed painkillers as the clot in her leg was very painful.
Impact of a pulmonary embolism (PE) deep vein thrombosis (DVT)
All the women we spoke to that had heparin injections had to do them themselves, which some felt apprehensive about at first. Alison T said it became painful at the injection site when she had to do it twice a day.
For some women, one of the distressing side effects of a blood clot was the impact that it could have on breastfeeding. Cate was in hospital with her 3 ½ week old baby and was advised that she would have to stop breastfeeding for 24 hours after they scanned her. “So I then had to juggle a baby who was feeding quite a lot with trying to express some milk as well.” Clare found it very upsetting to be told (wrongly) that the drugs she was given to treat her DVT meant she could not breastfeed her son. It caused a lot of disruption and anxiety.
Unlike some the other ‘near miss’ conditions, which are characterised by a fast moving emergency, having a blood clot during or after pregnancy can be drawn out and have long lasting effects. The length of time women need to take anticoagulation drugs varies depending on individual circumstances. Some need to take it for up to six months, others with greater risk need it long term.
Clare described her treatment as a “really long waiting game”. She was interviewed 8 months after she had her DVT and still didn’t feel her leg was back to normal. In the early weeks she found the pain and swelling in her leg very disabling. She could not move around the house to look after herself or her two children.
Rebecca developed a deep vein thrombosis in her legs during her caesarean surgery to deliver her third child (where it was discovered she had placenta percreta a condition in which the placenta invades the womb wall). Her surgery has left her with a drop foot. She has to wear a leg brace and she can no longer drive. It has changed their family life a lot.
Women also found it frightening to come to terms with how serious a blood clot might have been. Alison T was shocked to be told by doctors that pulmonary embolisms were one of the biggest killers in pregnant women. Cate said that she did not realise at the time what a ‘near miss’ she had had, because there wasn’t the time to go and look things up. “So it was only later when I went back that you realise actually how serious an embolism can be and actually how lucky I was especially given how long it was to have not been diagnosed.” Cate has since discovered that she has a hereditary blood clotting condition.

Being diagnosed with a blood clot can affect future pregnancies (see ‘Fertility and future pregnancies). Cate feels her family is complete with three children, so she is not too bothered that doctors told her that any further pregnancies would be very high risk. (She had placenta praevia - (where the placenta is in the wrong position and blocking the birth canal) and PE). Sophie has been told that if she got pregnant again she would need to be on medication for the entire pregnancy, which is a great worry to her.   

Last reviewed April 2016.


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