Immediate administration of two tablets of a combination oral contraceptive (each containing 50 μgof ethinyl estradiol and 0.5 mg norgestrel, such as Ovral birth control pills) followed by two more tablets 12 hours later (Yuzpe regimen) 3.
Four tablets of a combination birth control pill containing 35 μgof ethinyl estradiol and a progesterone followed by four more tablets 12 hours later 4.
Mifepristone as a single 10 mg dose (161) 5.
Placement of a copper-containing intrauterine device
These regimens are highly effective if administered within 120 hours after the sexual assault (159,162). The sooner the medications are taken, the more effective they are. Most regimens have a failure (pregnancy) rate of about 1.5%. Emergency contraception failure poses little teratogenic risk if the pregnancy continues (163). Some patients experience nausea and vomiting when given emergency contraception containing estrogen, which can be controlled with an antiemetic agent such as promethazine (12.5 mg every 4–6 hours) or ondansetron (4 mg every 6 hours). Emergency contraception should be repeated if vomiting occurs within 2 hours of taking the initial dose. Most women who take emergency contraception usually experience their next menstrual period within 3 days of the expected date. Women using mifepristone for emergency contraception may experience delayed onset of the subsequent menstrual period (161). Emergency contraception may delay but not prevent ovulation; for this reason, patients receiving emergency contraception should be encouraged to use contraception if further coital episodes occur during the cycle.
The risk of acquiring an STD from a rape is difficult to assess because the prevalence of preexisting STDs is high (43%) in rape survivors (164–166). The risk is estimated as follows: gonorrhea, 6% to 12%; trichomonas, 12%; chlamydia, 2% to 12%; syphilis, 5%.
1. Because it is difficult to differentiate between a preexisting STD and a newly contracted one attributable to a sexual assault, prophylaxis should be offered to all survivors. This is especially important because most sexual assault patients do not return for follow-up appointments (151). Prophylaxis should cover infections with Neisseria gonorrhoeae, Chlamydia trachomatis, trichomonas, bacterial vaginosis, incubating syphilis, and HIV. Recommendations include (165,167): a.
Ceftriaxone, 125 mg intramuscularly for the treatment of gonorrhea (if the patient is allergic to cephalosporins, spectinomycin, 2 g intramuscularly, or ciproﬂoxacin, 500 mg orally, may be used), PLUS: b.
A single dose of 1 g of azithromycin orally or 100 mg of doxycycline orally twice a day for 7 days for treatment of chlamydia (if the patient is pregnant at the time of the assault, erythromycin 500 mg orally four times a day for 7 days may be substituted for doxycycline), PLUS: c.
A single dose of 2 g of metronidazole orally for the treatment of trichomoniasis and/or bacterial vaginosis 2.