How it Works

Every month, your ovaries release one egg. It travels through your fallopian tubes until it reaches your uterus. Meanwhile, the lining of your uterus thickens in preparation for pregnancy, which begins if sperm successfully enters the egg and fertilizes it.
 

Oral contraceptives like Mercilon are usually made up of two types of hormones: estrogen and progestogen. These hormones prevent pregnancy in two ways: they stop your ovaries from releasing the egg and thicken the cervical mucus, which prevents sperm from reaching the egg.

Your body will shed the unfertilized egg along with the lining of the uterus naturally, resulting in your menstrual period.

To see what happens in your body every month, watch: The amazing female cycle

Go to the glossary for an overview of definitions.