RESUMEN
The aim of this study was to determine the prevalence of specific antibodies against rubella virus in pregnant women from Iztapalapa and Nezahualcóyotl areas of the valley of Mexico, in order to evaluate susceptibility to this virus in these areas. Serum samples collected from 5535 women between 15 and 44 years old were studied by the hemaglutination inhibition test. 92.6% of positivity was obtained and no significant difference was observed between different age groups. The prevalence of rubella antibodies in pregnant women was 92.4% for Iztapalapa zone and 92.8% for Nezahualcóyotl. The titles of antibodies against rubella virus more frecuently presented were 1:16 (36.3%) and 1:32 (29.6%). The data obtained in this study suggest that women attending Medical Services of the Mexican Institute of Social Segurity in reproductive age from the Iztapalapa and Nezahualcóyotl areas, do not need massive vaccination against rubella virus.