What are Progestin-Only Methods?
Progestin-only methods of contraception are a group of contraceptives that rely solely on the hormone progestin, without any estrogen. These methods include the progestin-only pill (POP), injectable contraceptives, the hormonal IUD, and the contraceptive implant. They are particularly beneficial for women who cannot use estrogen-containing methods due to certain health conditions or contraindications.
How Do Progestin-Only Methods Work?
Progestin-only methods work primarily by thickening the cervical mucus, which prevents sperm from entering the uterus. Some methods, like the progestin-only pill and implants, also inhibit ovulation. The hormonal IUD releases progestin locally within the uterus, creating a hostile environment for sperm and thinning the endometrial lining, making it less suitable for implantation.
Who Can Use Progestin-Only Methods?
Progestin-only methods are suitable for a wide range of women, including those who are breastfeeding, women with a history of thromboembolic disorders, or those who experience estrogen-related side effects. They are also a viable option for women over 35 who smoke, as estrogen-containing contraceptives pose higher risks for these individuals.
Progestin-Only Pills (POPs): These are taken daily and must be taken at the same time each day to maintain their effectiveness.
Injectable Contraceptives: Commonly known as Depo-Provera, this method involves an injection every three months.
Hormonal IUDs: The intrauterine device releases small amounts of progestin over several years (typically 3-5 years).
Contraceptive Implants: A small rod is inserted under the skin of the upper arm, releasing progestin over three years.
They are highly effective when used correctly.
They can be used by women who cannot take estrogen.
They can be started immediately postpartum, even during breastfeeding.
Some methods, like the hormonal IUD and implant, provide long-term contraception with minimal maintenance.
Irregular menstrual bleeding or spotting
Potential weight gain
Headaches or mood changes
Delayed return to fertility after discontinuation (notably with injectable methods)
Progestin-Only Pills: With typical use, the failure rate is about 9% per year.
Injectable Contraceptives: Less than 1% failure rate with perfect use, but around 6% with typical use.
Hormonal IUDs: Less than 1% failure rate, making it one of the most effective methods.
Contraceptive Implants: Less than 1% failure rate, similar to the hormonal IUD.
Bone Density: Long-term use of injectable contraceptives may be associated with a decrease in bone mineral density, but this effect is usually reversible upon discontinuation.
Breast Cancer Risk: Some studies suggest a slight increase in breast cancer risk, particularly with long-term use. However, the overall risk remains low.
Management of heavy menstrual bleeding
Reduction of menstrual pain and endometriosis symptoms
Protection against endometrial hyperplasia and cancer
Conclusion
Progestin-only methods are a versatile and effective form of contraception suitable for many women, particularly those who cannot use estrogen-containing methods. By understanding the different types, benefits, and potential side effects, women can make informed decisions about their reproductive health.
