How Combiation Birth Control Pills Prevent pregnancy .

Summary :
Normally during sex, your body sets the stage for pregnancy—sperm travels through the cervix, hoping to meet an egg released by the ovaries. However, when you take combination birth control pills, they completely rewrite the script. First, they stop your ovaries from releasing an egg, so there is nothing for the sperm to fertilize. Next, they thicken the cervical mucus, turning it into a tough barrier that makes it nearly impossible for sperm to reach the uterus. Lastly, they thin the lining of the uterus, so even if an egg were fertilized, it wouldn’t have a comfortable place to attach and grow. It’s a smart, well-coordinated defense system that keeps pregnancy off the table.