Introduction: Recent studies have shown that a single dose of 1.5 mg levonorgestrel is an effective and safe emergency contraceptive but detailed information on its menstrual side effects is lacking. This study assessed the vaginal bleeding patterns in healthy women who used the medication for emergency contraception.
Study design: A prospective observational study of 544 women who sought emergency contraception and volunteered to use a single dose of 1.5mg. levonorgestrel. They were assessed for bleeding patterns, pregnancies and side effects.
Results: The pregnancy rate was 0.7% (95%CI, 0.0-1.4). Early or timely return of menses occurred in 69% of the women while in 21% menses was late by more than a week. Normal vaginal bleeding occurred in 57% of the women while others had intermenstrual bleeding/spotting, premenstrual bleeding/spotting or menorrhagia. Non-menstrual side effects include nausea, vomiting, dizziness, headache, breast tenderness and low abdominal pain. All side effects were well tolerated by the women.
Conclusion: A single dose of 1.5mg LNG when used for emergency contraception is safe and reliable but is associated with menstrual disturbances that may be of concern to a small number of users.