CHMP concluded that emergency contraceptives containing levonorgestrel or ulipristal can continue to be adequate choice in women regardless of the body weight

28.07.2014

The CHMP has concluded its review of emergency contraceptives containing levonorgestrel or ulipristal. The review of these medicines was carried out due to their suspected lower efficacy in women with higher body weight, observed in certain clinical trials. The CHMP concluded that there is a trend for reduced effectiveness with increasing body weight in parts of the available clinical trials, however this trend was not observed in other clinical trials. Therefore, the CHMP having reviewed all the available proofs of efficacy for emergency contraception, concluded that the available data are not robust enough to draw definite conclusions on the reduced effectiveness of emergency contraception with increasing body weight. Based on the above, these medicines remain an appropriate choice for emergency contraception, independent from the body weight of the woman who uses it.

Information for women

Emergency contraceptives are used to prevent unintended pregnancy following unprotected sexual intercourse or contraceptive failure.
An EU-wide review was carried out to assess whether emergency contraceptives are less effective in overweight or obese women. It concluded that the limited data available do not support with certainty the conclusion that their contraceptive effect is reduced in women with high bodyweight.
Emergency contraceptives can continue to be taken after unprotected intercourse or contraceptive failure, regardless of the woman’s bodyweight. However, in order to maximise the likelihood that they will work, it is important that they are taken as soon as possible after unprotected intercourse.
Women are reminded that emergency contraception is an occasional "rescue” method, which does not work as well as regular methods of contraception, such as the pill.
Women who have any questions or concerns should speak to their doctor or pharmacist.

Information to healthcare professionals

Emergency contraceptives can continue to be used to prevent unintended pregnancy in women of any weight or body mass index (BMI). The available data are limited and not robust enough to support with certainty the conclusion of decreased contraceptive effect with increased bodyweight/BMI.
Healthcare professionals should continue to remind women that emergency contraception is an occasional "rescue” method and should not replace a regular contraceptive method.

For emergency contraceptives containing levonorgestrel, the EMA considered the following data:

a meta-analysis of two published studies 1,2, which primarily included Caucasian women, where a reduced contraceptive efficacy was observed with increased bodyweight or BMI (pregnancy rate was 0,96% [CI: 0,44-1,82] in women with BMI 18,5-25; 2,36% in women with BMI 25-30; and 5,19% [CI: 2,62-9,09] in women with BMI ≥30).
a meta-analysis of three WHO studies 3,4,5, which primarily included African and Asian women. The results of this analysis conflict with the results above and show no trend fro a reduced efficacy with increasing bodyweight/BMI (pregnancy rate was 0,99% [CI: 0,70-1,35] in women with BMI 18,5-25; 0,57% [CI: 0,21-1,24] in women with BMI 25-30; and 1,17% [CI: 0,24-3,39] in women with BMI ≥30).

Both meta-analyses did not include off-label use (i.e. intake later than 72 hours after unprotected sexual intercourse).

For ulipristal acetate, the EMA considered the following data:

a meta-analysis of four clinical studies that were submitted as part of the application for marketing authorisation of ellaOne 6, which suggests a possible trend for a reduced contraceptive efficacy with high bodyweight or BMI, although confidence limits overlap (pregnancy rate was 1,23% [CI: 0,78-1,84] in women with BMI 18,5-25; 1,29% [CI: 0,59-2,43] in women with BMI 25-30; and 2,57% [CI: 1,34-4,45] in women with BMI ≥30).

You may read more about the emergency contraceptive review on the EMA webpages, or here.

Reference:

Creinin MD et al. Progesterone receptor modulator for emergency contraception: a randomized controlled trial. Obstet Gynecol 2006;108: 1089-97.
Glasier A et al. Ulipristal acetate versus levonorgestrel for emergency contraception: a randomized noninferiority trial and meta-analysis. Lancet 2010; 375: 555-62.
von Hertzen H et al. Randomised controlled trial of levonorgestrel versus the Yuzpe regimen of combined oral contraceptives for emergency contraception. Lancet 1998; 352: 428-33.
von Hertzen H et al. Low dose mifepristone and two regimens of levonorgestrel for emergency contraception: a WHO multicentre randomised trial. Lancet 2002; 360: 1803-10.
Dada OA et al. A randomized, double-blind, noninferiority study to compare two regimens of levonorgestrel for emergency contraception in Nigeria. Contraception 2010; 82: 373-378.
Klinička ispitivanja HRA2914-507, HRA2914-508, HRA2914-509 and HRA2914-513. For more information on these studies, see here the CHMP assessment report for ellaOne.