From the Guidelines
The recommended emergency contraception for this patient is ulipristal acetate 30 mg as a single oral dose, taken as soon as possible within 120 hours of unprotected intercourse, due to its potentially higher efficacy compared to levonorgestrel, especially since the patient is close to her fertile window and had intercourse last night. Given the patient's situation, with her last menstrual period being 9 days ago and having unprotected intercourse last night, emergency contraception is appropriate to prevent pregnancy. The patient can choose between ulipristal acetate 30 mg as a single oral dose, which requires a prescription, or levonorgestrel 1.5 mg as a single oral dose, which is available over-the-counter without a prescription, as stated in the guidelines by 1. However, considering the patient's weight is not mentioned, and assuming she may weigh more than 165 pounds, ulipristal acetate may be more effective, as suggested by 1. Emergency contraception works primarily by delaying or inhibiting ovulation, preventing fertilization. The patient should be advised that her next menstrual period might be early or delayed by a few days, and if she doesn't have a period within three weeks, she should take a pregnancy test. Until her husband's vasectomy is complete and confirmed effective, she should either restart her oral contraceptives or use barrier methods to prevent pregnancy. Side effects of emergency contraception are generally mild and may include nausea, headache, fatigue, and breast tenderness, as mentioned in 1. It is essential to note that the copper IUD is also an effective option for emergency contraception, with a failure rate of less than 1%, but it may not be the most convenient option for this patient, as stated in 1. In any case, the patient should be informed about all available options and their effectiveness, as well as potential side effects, to make an informed decision about her emergency contraception.
From the FDA Drug Label
The sooner you take emergency contraception, the better it works You should use levonorgestrel tablet within 72 hours (3 days) after you have had unprotected sex. If levonorgestrel tablet is taken as directed, it can significantly decrease the chance that you will get pregnant About 7 out of every 8 women who would have gotten pregnant will not become pregnant. The primary efficacy analyses were performed on subjects less than 36 years of age who had a known pregnancy status after taking study medication Ellastatistically significantly reduced the pregnancy rate, from an expected rate of 5.5% to an observed rate of 2. 2%, when taken 48 to 120 hours after unprotected intercourse. Ellastatistically significantly reduced the pregnancy rate, from an expected 5.6% to an observed 1. 9%, when taken within 72 hours after unprotected intercourse.
The patient is 39 years old, which is outside the primary efficacy analysis age range of less than 36 years. However, emergency contraception can still be effective.
- Ulipristal acetate can be taken up to 120 hours after unprotected intercourse, and
- Levonorgestrel should be taken within 72 hours after unprotected intercourse. Given the patient's situation, ulipristal acetate may be a more suitable option since the time of unprotected intercourse was last night, which is within the 120-hour window. It is essential to note that the patient should take the emergency contraception as soon as possible to increase its effectiveness 2 3.
From the Research
Emergency Contraception Options
- The patient has several options for emergency contraception, including ulipristal acetate (UPA) and levonorgestrel (LNG) 4, 5, 6, 7, 8.
- UPA is a selective progesterone receptor modulator that can be used up to 5 days after unprotected intercourse, while LNG is only approved for use up to 72 hours after unprotected intercourse 4, 5, 7, 8.
Efficacy of Ulipristal Acetate
- Studies have shown that UPA is at least as effective as LNG when used within 72 hours of unprotected intercourse, and may be more effective when used between 72 and 120 hours after unprotected intercourse 4, 5, 7.
- A meta-analysis of two randomized clinical trials found that UPA had a pregnancy risk 42% lower than LNG up to 72 hours and 65% lower in the first 24 hours following unprotected intercourse 5, 8.
Safety and Side Effects
- The most commonly reported adverse events associated with UPA include headache, nausea, and abdominal pain 4, 7.
- UPA may also delay the onset of menstruation by a mean of 2.1 to 2.8 days 4.