The term “morning-after pill” refers to oral medications used as emergency contraception (EC) designed to prevent pregnancy after unprotected sexual intercourse or contraceptive failure. This medication is distinctly different from the abortion pill, which is used to terminate an established pregnancy. EC functions only to prevent a pregnancy from beginning. Its effectiveness depends heavily on how quickly it is taken.
Identifying the Appearance of Emergency Contraception
The physical appearance of emergency contraceptive pills varies depending on the active ingredient they contain. Two main types are available in the United States. The most common type uses the active ingredient levonorgestrel and typically appears as a single, almost white, round tablet. This pill often includes an imprint code, such as “G00,” stamped on one side for identification.
The second primary form of emergency contraception, which contains ulipristal acetate, usually presents as a white to off-white, round tablet. This tablet is often slightly curved and is frequently marked with the word “ella” on both sides. Recognizing these differences is important because the two types of EC are not interchangeable and have different requirements for use.
Distinguishing Between the Active Ingredients
The difference in appearance stems from the two distinct active compounds used in emergency contraception. Levonorgestrel is a synthetic hormone classified as a progestin, which works similarly to the hormone progesterone naturally produced by the body. This type of EC is widely available over-the-counter at pharmacies and requires no prescription or age restriction for purchase.
The second compound, ulipristal acetate, is a selective progesterone receptor modulator, meaning it acts by modifying the effects of progesterone. This chemical structure gives ulipristal acetate a different pharmacological profile compared to levonorgestrel. Unlike the levonorgestrel-based pill, ulipristal acetate generally requires a prescription or an ID check by a pharmacist to access, though this varies by location.
How Emergency Contraception Works
Emergency contraception primarily functions by interfering with the process of ovulation, which is the release of an egg from the ovary. Both types of pills work by preventing or significantly delaying the surge of Luteinizing Hormone (LH) needed to trigger ovulation. If an egg is not released, there is nothing for the sperm to fertilize, thereby preventing pregnancy.
The pills are most effective when taken before the LH surge has begun. If ovulation has already occurred before the pill is taken, the medication is ineffective at preventing pregnancy. Emergency contraception does not interrupt a pregnancy once a fertilized egg has successfully implanted in the uterine wall.
Critical Timing and Accessibility
The effectiveness of emergency contraception depends heavily on how soon the pill is taken after unprotected intercourse. Levonorgestrel-based EC is most effective when taken within 72 hours (three days). Although it may have some reduced effect up to 120 hours, efficacy decreases sharply with every passing hour.
Ulipristal acetate maintains a higher level of effectiveness for a longer duration, up to 120 hours (five days) after unprotected sex. Accessing EC is straightforward: levonorgestrel products are stocked on the shelves of most pharmacies, while ulipristal acetate requires a prescription or can be obtained through various health clinics. Side effects include headaches, dizziness, nausea, and minor disruption to the timing of the next menstrual period.