A prospective controlled study of the effect on blood pressure of contraceptive preparations containing different types and dosages of progestogen

A prospective controlled study investigated the effects of oral contraceptives (OCs) on blood pressure in 485 women who were between 17-46 years old and had blood pressures of 140/90 mmHg at entry. The women were divided into 7 groups depending on the chosen method of contraception: 1) IUD or barrier method (controls); 2) ethinyl estradiol 30 mcg plus levonorgestrel 150 mcg (Microgynon 30 or Ovranette); 3) norethisterone 350 mcg (Micronor); 4) norgestrel 75 mcg (Neogest); 5) norethisterone enanthate 200 mcg intramuscularly every 2 months for the 1st 6 months then every 3 months thereafter; 6) ethinyl estradiol 30 mcg plus ethynodiol diacetate 2 mg (Conova 30); 7) and ethynodiol diacetate 500 mcg (Femulen). Blood pressures were measured every 3 months by the family planning clinic nurse under standardized conditions using an Elag-Koln automatic sphygmomanometer. After 1 year blood pressure had risen significantly (P0.05) in the 137 women taking ethinyl estradiol plus levonorgestrel (mean systolic and diastolic rises 6.4 and 2.7 mmHg respectively) and in the 91 women taking ethinyl estradiol plus ethynodiol diacetate (mean systolic and diastolic rises 6.2 and 3.0 mmHg respectively). The 94 women taking the progestogen-only preparations and the 143 women in the control group showed no increases in blood pressure. These data were confirmed after 2 years of follow-up. (authors modified)