Many people notice that once they are pregnant, their periods stop. But why does this happen?

The Usual Process

• Normally, if no fertilization happens, the uterus lining sheds → period.
• But pregnancy changes everything.

What Happens in Pregnancy

• After fertilization, the fertilized egg attaches to the uterus lining.
• The body produces hormones (progesterone, hCG) that keep the lining in place.
• This lining becomes the baby’s support system (part of the placenta).

Why Periods Stop

• The body no longer needs to shed the lining.
• Instead, it maintains the lining to nourish the growing baby.
• Menstruation and pregnancy cannot happen together because they require opposite conditions.

Important Note

Some people may have light spotting early in pregnancy, but this is not the same as menstruation.