Menarche and Menstruation in Various Ethnic Groups in Israel

Abstract

SUMMARY Sexual development may be influenced by geographic factors (temperature, humidity, altitude, light), socioeconomic factors (nutrition, public health, family size), and genetic factors (population, familial heredity). Most of them are largely interrelated and difficult to define. An anamnestic study has been carried out in Israel on Ashkenazi, non-Ashkenazi, and Arab women aged 19 to 60. The age of menarche appeared to be significantly different for Ashkenazi vs. non-Ashkenazi, while no significant difference was found between Arabs and either of the two Jewish groups. Highly significant differences were found for the length of the menstrual cycle, although this finding should be considered with caution. No significant relationship was found between age of menarche and length of the menstrual cycle.