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Studies on oral contraceptives are flawed

I am extremely disappointed that the BMJ has been prepared to publish studies that are as seriously flawed as these

News: Lower clot risk with levonorgestrel

Many GPs read the BMJ and read the headline, but not the detail, and will not read the rapid response written by the two leading national experts who feel these studies are methodologically flawed.

The methodologically sound large prospective study published by Dinger et al in 2007 found no difference in thromboembolic risk between pills containing different progestogens, including those containing drosperinone.

Some 25% of women choose combined oral contraception as their favoured method. Between 25-40% of these abandon the method during the first year because of adverse events or other concerns, without letting their prescriber know, and opt for less reliable methods.

If we are going to continue to reduce the numbers of unwanted pregnancies in the UK, we need to have flexibility about prescribing to get the right product for the right woman at the right time, using the UK Medical Eligbility Criteria as our safety manual.

Levonorgestrel-containing pills do not suit all women, so before removing other progestogen-containing pills from our formularies we need to make sure that the evidence supporting these decisions is founded – and not be influenced by another ill-founded ‘pill-scare’.

From Dr Anne Connolly, Chair of the Primary Care Women’s Health Forum and a GP in Bradford, via