Progestogen only contraception and venous thromboembolism – is accepted
clinical practice at odds with manufacturer’s guidance?
Sexual and Reproductive Healthcare Partnership, Hull, UK
Introduction: Progestogen only contraceptives have been regarded as
the method of choice for clients requesting hormonal contraception with a
history of venous thromboembolism (VTE), oestrogen being contraindicated. (World
Health Organisation (WHO). Medical eligibility criteria for contraceptive use.
Geneva, Switzerland: WHO 2000. Guillebaud J. Contraception your questions
answered 3rd edition. Churchill Livingstone, Harcourt Publishers, Edinburgh,
1999; 285–288). Introducing clinical protocols for the newer products Implanon
& Cerazette, it became evident that ‘active venous thromboembolic disorder’
contraindicated their use. This in turn lead to a closer examination of the
guidance for the more traditional progestogen only products.
Aims and methods: To elucidate the precise cautions/contraindications
of all the progestogen only contraceptives with regard to VTE, firstly according
to the product information issued by the manufacturers and secondly according to
the British National Formulary (BNF). There was also communication with the
pharmaceutical company Janssen-Cilag.
Results: In general the guidance from the manufacturers regarding VTE
risk with the traditional progestogen only pills (POP) was even more stringent
than for the newer products; with ‘history of’ VTE as well as ‘current,
existing or active’ VTE often being a contraindication to use. This was at
variance both with accepted clinical practice and with advice in the BNF.
Interestingly in the case of Micronor, the product information for an identical
pharmaceutical product in a higher dose (Micronor HRT) contained no caution
regarding thromboemolic disorders on commencing treatment, unlike its
contraceptive counterpart. The terminology used in the product information was
often ambiguous, open to differing interpretations.
Conclusions: The information available regarding the use of
progestogen only contraception in clients with history of VTE is inconsistent
and confusing. Accepted clinical practice appears to be at odds with