ABSTRACT
Circulatory disease and choice of COC The objective of prescribing is efficacy with maximum safety, and with the Pill this primarily means safety in relation to arterial and venous circulatory disease. This safety depends on choosing appropriate users as much as the appropriate Pill. The following is a useful framework for this process:
Risk factors for circulatory disease are of greatest relevance, and the research available since 1995 means we should now consider separately for each woman the risk factors for venous and arterial thrombosis (pp. 30-1, 34-5). Questions (2) and (3) identify the ‘dangerous’ women, or rather the ‘most unsafe’ and the ‘less unsafe’ women respectively, for the Pill. The answers are pivotal in answering the next questions in this sequence:
All modern low-dose COCs contain ethinylestradiol (EE) combined with a variety of progestogens (Figure 5 and Table 3). Note that there are six main ‘ladders’ of progestogens, since in vivo norethisterone acetate (NETA) is converted with great efficiency to norethisterone (NET). These progestogens are usefully classified into two groups. The first is often, but unhelpfully, referred to as second generation (LNG and NET with its prodrugs). The other group is the remainder, including those with desogestrel (DSG) and gestodene (GSD) – formerly
termed third generation – but also drospirenone (DSP) and (not displayed in Figure 5) cyproterone acetate (CPA). Norgestimate (NGM) as in Cilest™ (Janssen-Cilag), with 35 µg of EE, is, in my view, effectively also in this group (see p. 37) of formulations, which are all more oestrogendominant than LNG-or NET-containing products.
