Emergency contraception prevents pregnancy after unprotected sex or contraceptive failure. It is a backup, not a routine birth control method, intended for immediate action to reduce pregnancy risk.
Understanding Emergency Contraception
Emergency contraception primarily involves two types of pills: levonorgestrel-based and ulipristal acetate-based. Levonorgestrel (LNG) pills, like Plan B One-Step, contain a synthetic hormone that delays or inhibits ovulation. By preventing ovulation, fertilization cannot occur, thus averting pregnancy. These pills are most effective when taken soon after unprotected sex.
Ulipristal acetate (UPA) pills, such as Ella, are another form of emergency contraception. UPA is a progesterone receptor modulator that also delays or inhibits ovulation. UPA can delay ovulation even after the luteinizing hormone (LH) surge has begun, a point at which LNG might no longer be effective. Neither pill type terminates an existing pregnancy. A copper intrauterine device (IUD) also serves as a highly effective emergency contraceptive, preventing fertilization through chemical changes to sperm and eggs.
Frequency of Use and Effectiveness
Emergency contraceptive pills are not designed for frequent or routine use as primary birth control. Their effectiveness is lower than consistent, regular contraception. Efficacy decreases the longer the time elapsed since unprotected sex. Levonorgestrel is most effective within 72 hours (three days), though it can be used up to 120 hours (five days) with diminishing efficacy.
Ulipristal acetate remains effective for up to 120 hours (five days) after unprotected sex, and is considered more effective than levonorgestrel, especially between 72 and 120 hours. A higher body mass index (BMI) can also reduce the effectiveness of levonorgestrel-based pills. While it is safe to take emergency contraception multiple times, it is not recommended as a primary method.
Potential Effects of Repeated Use
Repeated use of emergency contraceptive pills can lead to temporary effects, though it does not cause long-term harm or infertility. One common issue is menstrual cycle disruption, manifesting as irregular periods, changes in bleeding patterns, or periods that are earlier or later than expected. Spotting or bleeding unrelated to a period can also occur.
General side effects like nausea, headache, breast tenderness, abdominal cramping, dizziness, and fatigue may also be experienced more frequently with repeated use. These side effects are typically mild and resolve without further medication. Emergency contraception does not offer protection against sexually transmitted infections (STIs). These temporary disruptions and the lack of STI protection highlight its role as a backup, not a primary method.
Choosing Ongoing Contraception
Given that emergency contraception serves as a backup, considering ongoing, regular birth control methods is a more consistent approach to pregnancy prevention. Various effective options are available, including oral contraceptive pills, intrauterine devices (IUDs), contraceptive implants, patches, and vaginal rings. These methods provide reliable, continuous protection against pregnancy when used correctly.
Many regular contraceptive methods also offer benefits beyond preventing pregnancy, such as regulating menstrual cycles, reducing menstrual cramps, lightening periods, and potentially improving acne. Some hormonal birth control methods can even lower the risk of certain cancers, like ovarian and endometrial cancer. Consulting a healthcare professional is advisable to discuss individual needs and determine the most suitable ongoing contraceptive method.