Measuring sexual orientation and related STD rates in US women aged 15-44 years

Objectives. To estimate the proportion of homosexual and bisexual women classified by different combinations of self-reported sexual identity, behavior, and attraction in the US women aged 15-44 years; and to estimate self-reported STD rates for the classified homosexual and bisexual women. Methods. The 2002 National Survey of Family Growth (NSFG) with newly added questions of sexual identity and sexual attraction was used for data analysis. Eight measures were used to classify women into homosexual, bisexual, or heterosexual categories based on self-reported sexual behavior, sexual identity, and sexual attraction. Past viral STD rates were also based on self-reported events. Results. The estimated proportion of homosexual or bisexual women aged 15-44 years may vary depending on how women are classified: 0.7%-1.9% for homosexual and 2.1%-5.4% for bisexual based on eight measures. The past viral STD rates were estimated to range significantly (p<0.05) by sexual orientation: 2.3%-6.9% for homosexual women, 8.7%-10.0% for heterosexual women, and 11.2%-17.2% for bisexual women according to those eight measures. Conclusions. The proportion of homosexual and bisexual women varied widely according to the measures used. In terms of STD issues, it would be better if the homosexual and bisexual women were classified separately, because their past viral STD rates were significantly different. The public health establishment needs to consider the female homosexual and bisexual populations as separate entities for STD/HIV prevention interventions.