ICSE Class 10 Answered
Hormonal changes cause a delay in the menstrual cycle after pregnancy.
Breastfeeding is the biggest factor which affects period because prolactin, the hormone responsible for breast-milk production, suppresses ovulation.
Post-pregnancy, the mothers may have longer or shorter menstrual cycles, a heavier or lighter flow, and even the cycle length can be different. It is also possible to have increased or decreased cramping. This is because the uterus grows during pregnancy; then it shrinks after delivery. The endometrial lining, what is shed during a period, has to remodel itself as it goes through these changes.
Because of all these factors, the menstrual cycle might appear to have stopped temporarily.