Globally, unplanned pregnancies and sexually transmitted infections (STIs) persist as significant threats to women’s reproductive health. Barriers to the use of modern contraceptives by women might inhibit uptake of novel woman-controlled methods for preventing STIs/HIV. Use of modern contraceptives and perceptions and attitudes towards contraceptive use were investigated among women in Antananarivo, Madagascar, using qualitative research. The hypothetical acceptability of the diaphragm – a woman-controlled barrier contraceptive device that also holds promise of protecting against STIs/HIV – was assessed. Women consecutively seeking care for vaginal discharge at a public health clinic were recruited for participation in a semi-structured interview (SSI) or focus group discussion (FGD). Audiotaped SSIs and FGDs were transcribed, translated and coded for predetermined and emerging themes. Of 46 participating women, 70% reported occasional use of male condoms, mostly for preventing pregnancy during their fertile days. Although women could name effective contraceptive methods, only 14% reported using hormonal contraception. Three barriers to use of modern contraceptives emerged: gaps in knowledge about the range of available contraceptive methods; misinformation and negative perceptions about some methods; and concern about social opposition to contraceptive use, mainly from male partners. These results demonstrate the need for programmes in both family planning and STI prevention to improve women’s knowledge of modern contraceptives and methods to prevent STI and to dispel misinformation and negative perceptions of methods. In addition, involvement of men will probably be a critical component of increased uptake of woman-controlled pregnancy and STI/HIV prevention methods and improved health.