Marriage conception interval.

The relationship between length of menstrual cycle and first birth interval is explored using data for 400 urban and 190 rural women in Lodha, India. The women were divided into three groups: urban women married before menarche, urban women married after menarche, and rural women married before menarche. The results indicate that "marriage-conception is delayed with longer menstrual cycles. Thus the females with longer menstrual cycle lengths appear to have a lesser chance of reproductive performances during the span of their reproductive life than those who are with shorter cycle lengths."