Acute Care Nurse Practitioner Exam Prep 2025 – Complete Practice Resource

The primary action of combined oral contraceptive pills is to enhance cervical mucus thickness. This mechanism of action plays a significant role in preventing pregnancy. When combined oral contraceptives are taken, the hormones in these pills, which include both estrogen and progestin, work together to thicken the cervical mucus. This thickened mucus creates a barrier that makes it more difficult for sperm to travel through the cervix and reach an egg, thus reducing the likelihood of fertilization.

In addition to this, combined oral contraceptives also suppress ovulation. They do this by inhibiting the hormonal signals that trigger the release of an egg from the ovaries. Thus, while changing the dosage of estrogen and progestin and inhibiting estrogen production are relevant aspects of how contraceptives may be formulated and how hormone regulation occurs in the body, they do not directly relate to the primary mechanisms through which combined oral contraceptives prevent pregnancy.