A placebo-controlled, double-blind study was carried out to assess the direct hormonal effects of combined and progestogen-only oral contraceptives on well-being and sexuality of women in two contrasting cultures. One-hundred-fifty women, who had been sterilised or whose partners had been vasectomised, were recruited from two centres-Manila, Philippines, and Edinburgh, Scotland. After one month pretreatment assessment, women were randomly assigned to one of three treatments (combined oral contraceptive (COC), progestogen-only pill (POP), or placebo; 50 within each treatment group, 25 per centre) and continued on treatment for four months. Assessment was by daily ratings, questionnaires and interviews. The COC adversely affected sexuality in the Edinburgh women, with 12 of the 25 women in this group also reporting the side effect of reduced sexual interest. There were modest negative effects of the combined pill on mood, more noticeable in the Edinburgh women. The POP was associated with no adverse effects on sexuality and some improvement in well-being in both centres. Possible explanations for the apparent lack of adverse effects in the Manila women are discussed. The negative effects reported may be less evident in women using the COC for contraceptive purposes but may lead to discontinuation in some women and warrant further investigation.