The seroprevalence of HIV infection among pregnant women is known for the Ile-de-France and PACA regions, thanks to the anonymous, non-correlated PREVAGEST surveys conducted between 1991 and 1994. The Sentinelles network of maternity wards was established in 1987 to monitor epidemiological trends throughout the country. This study compares data from the Sentinelles network in 128 maternity wards for the periods 1987–1989 and 1992–1993 in terms of the number of HIV-positive pregnancies, geographic distribution, mode of transmission, and pregnancy outcome.