OBJECTIVE: To model the effectiveness that can be obtained if levonorgestrel-only
emergency contraception (EC) acts only through disrupting ovulation, in relation to other …

Background: Recent studies have identified that levonorgestrel administered orally in
emergency contraception (LNG-EC) is only efficacious when taken before ovulation …

BACKGROUND: Although widely used, the mechanisms of action of the levonorgestrel
emergency contraceptive pill (LNG ECP) are still unclear. There are increasing data to …

There has been much debate regarding levonorgestrel emergency contraception's (LNG-
EC's) method of action since 1999 when the Food and Drug Administration first approved its …

BACKGROUND: This study was conducted to evaluate the effects of levonorgestrel
administration for emergency contraception (EC) on bleeding pattern and pituitary-ovarian …

BACKGROUND: Levonorgestrel is an effective method for emergency contraception (EC)
and is used worldwide. Consistent with its mechanism of action in delaying ovulation, the …

OBJECTIVE: To assess the possibility of a postfertilization effect in regard to the most
common types of hormonal emergency contraception (EC) used in the US and to explore the …

Purpose Levonorgestrel-only emergency contraception (EC) inhibits ovulation to prevent
fertilization. Misconceptions regarding its mechanism of action contribute to low use in some …

The use of levonorgestrel (LNG) alone or combined with ethinylestradiol (Yuzpe regimen),
for hormonal emergency contraception (HEC) has been approved in several countries …

BACKGROUND: The contraceptive efficacy of emergency contraceptive pills containing
levonorgestrel (LNG-EC) has been estimated in most previous studies by judging the day of …