Medical abortion- Up to what gestational age?

K. Gemzell Danielsson

Department of Woman and Child Health, Division for Obstetrics &.Gynecology, Karolinska University Hospital/ Karolinska Institutet, Stockholm, Sweden

Medical abortion with a combined regimen of mifepristone and a prostaglandin analogue was first approved in France in 1988. Today medical abortion is available in around 30 countries. Except for the UK, Sweden and Norway where the method is approved up to 63 days, other approvals are limited to 49 days.

Since the introduction of the method research has focused mainly on the following issues: To find the optimal dose of mifepristone, the optimal type, dose and route of administration of prostaglandin, to increase acceptability of the method and to define the duration of pregnancy for which it can be used.

During this time it has been shown that the dose of mifepristone can be reduced without affecting its priming effect on the myometrium and cervix. Misoprostol, has emerged as the most optimal prostaglandin analogue with its effect being dependent on the duration of pregnancy, and on the dose and the route of administration.

With the introduction of mifepristone the non-surgical, non-invasive methods for 2nd trimester abortion could be dramatically improved and has become the recommended method in many centres. The induction-to-abortion interval is on average 6,5 hours and more than 70% of women are treated as day care patients.

After 24 weeks of pregnancy the dose of misoprostol has to be reduced. This continues gradually until term.

More recently medical abortion has also become increasingly used in 10 to 13 weeks. In this interval the comparison between medical and surgical abortion has shown more side-effects in the group using medical termination while there is no difference in major complications. The high level of acceptance and the 94-95 per cent effectiveness let to the conclusion of medicinal termination as being an alternative for women also between 10 to 13 weeks of pregnancy,

In conclusion the combined treatment with 200 mg mifepristone and misoprostol is a highly effective and safe method to terminate pregnancy provided that the dose and route of misoprostol is adjusted to the pregnancy length.