The morning-after pill, also known as emergency contraception (EC), is a medication used to prevent pregnancy after unprotected sexual intercourse or a known method failure, such as a broken condom. Its mechanism focuses on preventing or delaying ovulation, which is the release of an egg from the ovary. EC is not a form of abortion; it will not end an established pregnancy, nor is it intended for use as a regular method of birth control.
Understanding the Different Types of Emergency Contraception
Emergency contraception pills primarily rely on one of two active ingredients. The most widely available type contains Levonorgestrel, which is a synthetic hormone similar to progesterone. This ingredient works by inhibiting the surge of Luteinizing Hormone (LH) that triggers ovulation, effectively preventing the egg’s release.
The other type of oral emergency contraception uses Ulipristal Acetate, which is a selective progesterone receptor modulator. Ulipristal Acetate is considered more effective than Levonorgestrel because it can delay ovulation even after the LH surge has begun. This difference means Ulipristal Acetate provides a longer window of potential effectiveness. Both types work before the fertilization of the egg or implantation in the uterus.
Standard Dosage Instructions for Emergency Contraception
The required dosage depends entirely on the active ingredient and the specific formulation of the product. The current standard Levonorgestrel regimen is a single dose of 1.5 milligrams, typically packaged as one tablet. Taking this single tablet as soon as possible is the recommended procedure for maximum effectiveness.
An older Levonorgestrel format, consisting of two 0.75 milligram tablets, is still available in some places. If you purchase this two-pill version, both tablets must be taken together at the same time to achieve the standard 1.5 milligram dose. Taking the pills twelve hours apart is an outdated instruction that is no longer recommended.
The entire dose must be swallowed whole with water. There is no requirement to take the medication with food, although some individuals find that doing so may help minimize potential nausea.
In contrast, Ulipristal Acetate is always administered as a single 30 milligram tablet. This medication is designed only as a one-pill treatment, and no other dosage is necessary or recommended.
The Importance of Timing and Efficacy Windows
The effectiveness of any emergency contraception pill is directly tied to how quickly it is taken after unprotected intercourse. The active ingredients work best when administered before the process of ovulation is complete. The sooner the pill is taken, the higher the likelihood that it will successfully prevent pregnancy.
For Levonorgestrel, the pill is approved for use up to 72 hours, or three days, after unprotected sex. Its efficacy decreases significantly with every passing day within this window. Waiting until the third day substantially lowers the chance of the pill working compared to taking it within the first 24 hours.
Ulipristal Acetate offers a longer window of use, remaining effective for up to 120 hours (five days) following unprotected intercourse. Its effectiveness remains relatively stable throughout this entire five-day period. This extended timeframe often makes it the preferred option when more than three days have passed.
Troubleshooting and Safety After Taking the Pill
Following the administration of emergency contraception, there are several safety steps to consider. If vomiting occurs shortly after taking the pill, the medication may not have been fully absorbed, requiring a repeat dose. For Levonorgestrel, if vomiting happens within two hours of taking the dose, a second dose should be taken immediately.
The window is slightly longer for Ulipristal Acetate; if vomiting occurs within three hours of taking the pill, the dose should be repeated. It is advisable to consult a healthcare provider or pharmacist for guidance on obtaining a repeat dose and for advice on taking an anti-nausea medication beforehand.
Certain medications can impact the effectiveness of oral emergency contraception. Drugs that induce liver enzymes, such as some anti-seizure medications and antibiotics, can cause the body to break down the hormones in the EC pill too quickly. In these cases, a double dose of Levonorgestrel or the use of a copper Intrauterine Device (IUD) may be recommended as alternatives.
Body weight can also be a factor, particularly with Levonorgestrel, which may have reduced efficacy in individuals over 70 kilograms. Ulipristal Acetate or the copper IUD are typically suggested as more reliable options for individuals in this situation.
Following treatment, common side effects include headache, nausea, and changes to the next menstrual cycle, which may arrive earlier or later than expected. If the next menstrual period is delayed by more than one week, a pregnancy test should be taken to confirm the outcome.