Progestin-only pills, or mini-pills, may be prescribed to help women manage heavy periods, as well as when a woman is looking for contraception when breastfeeding, has problems with estrogen-based contraceptives, or is at a heightened risk of blood clots.
Progestin-only pills lead to lighter periods, but do not regulate periods in the same way that combination pills do.
How Do Progestin-only Pills Affect Periods?
Progestin-only pills, like Camila and Norethindrone, prevent pregnancy by thinning the endometrial lining and thickening cervical mucus, making it more difficult for sperm to reach an egg and for an egg to implant. They may also stop ovulation from occurring.
However, unlike combination birth control pills, progestin-only pills do not necessarily lead to a regular, predictable period. You take an active progestin-only pill every day, unlike with combination pills that have a placebo week, when you experience a period. Very often women on progestin-only pills experience irregular bleeding or spotting, especially for the first three to six months as their bodies adjust to the hormones. Over time their cycles may become more regular, but this takes several months to occur.
Most women who take progestin-only pills will see lighter periods, a reduction in severe premenstrual symptoms, and less cramping, because progestin thins the endometrial lining there is less lining to shed. Some women on progestin-only birth control will eventually experience few or no periods at all.