What Is Plan B?
Plan B is a type of emergency contraception that contains levonorgestrel, a synthetic progestin hormone, which works primarily by preventing ovulation and fertilization. Plan B is not intended for routine use as a regular contraceptive method and does not terminate an existing pregnancy.
Active Ingredient
Levonorgestrel is a synthetic progestin hormone similar to progesterone, which occurs naturally in the body.
Mechanism of Action
- Preventing Ovulation: By inhibiting the release of an egg from the ovary.
- Thickening Cervical Mucus: Making it more difficult for sperm to reach the egg.
- Altering the Endometrium: Making it less receptive to implantation by a fertilized egg, if fertilization occurs.
Side Effects
Common side effects may include nausea, abdominal pain, fatigue, headache, and changes in menstrual bleeding patterns. Serious side effects are rare.