Prevalence of rubella antibodies: comparison between women with pregnancy induced by infertility treatments and those with spontaneous pregnancy.

Widespread rubella epidemics have sometimes occurred in Japan. We compared the prevalence of rubella antibodies in women who had conceived after infertility treatments and in those who had conceived spontaneously. We reviewed the obstetric records of nulliparous Japanese women who had conceived after infertility treatments and whose babies had been born at the Japanese Red Cross Katsushika Maternity Hospital from 2014 to 2018. No significant differences in the rates of women with rubella antibody titers < 8 or < 32 emerged between those who had been treated and those who had not (titer < 8: 4.1 vs. 3.4%, p = 0.58; titer < 32: 17.3 vs. 15.3%, p = 0.45, respectively). It is necessary to thoroughly implement pre-conception care concerning the risk of congenital rubella infection for women undergoing infertility treatments, especially in Japanese obstetric clinics.