Comparing medical treatments for miscarriage with waiting for nature to take its course or using surgery to empty the womb

Miscarriage is when a pregnant woman loses her baby before the baby would be considered able to survive outside the womb, i.e. before 24 weeks' gestation. Miscarriage occurs in about 10% to 15% of pregnancies and the signs are bleeding usually with some abdominal pain and cramping. The cause of miscarriage is often unknown, but most are likely to be due to abnormalities in the baby’s chromosomes. Women experiencing miscarriage may be quite distressed, and there can be feelings of emptiness, guilt and failure. Fathers can also be affected emotionally. Traditionally, surgery (curettage or vacuum aspiration) has been the treatment used to remove any retained tissue and it is quick to perform. It has now been suggested that medical treatments (usually misoprostol) may be as effective and may carry less risk of infection. This review was undertaken to compare medical treatments with surgery or with no treatment. The review identified 15 studies involving 2750 women and all these studies were of women less than 13 weeks' gestation. There were a number of different ways of giving the drugs and so there are limited data for each comparison. Overall, the review found no difference in the success between misoprostol and waiting for spontaneous miscarriage, nor between misoprostol and surgery. The overall success rate was over 80% and sometimes as high as 99%, and one study identified no difference in subsequent fertility between treatments. Vaginal misoprostol was compared with oral misoprostol in one study which found  no difference in success but there was more diarrhoea with oral misoprostol.  However, women on the whole seemed happy with their care whichever treatment they were given. The review suggests that misoprostol or waiting for spontaneous expulsion of fragments are important alternatives to surgery, but women should be offered an informed choice. Further studies are clearly needed to confirm these findings. There is an urgent need for studies on women who miscarry when more than 13 weeks' gestation.