LONDON (AP) — The European Medicines Agency says it has started a review of emergency contraceptives to see if they work less well in heavier women.

In November, French drug maker HRA Pharma announced its morning-after pill Norlevo was less effective in women weighing more than 75 kilograms (165 pounds) and that it didn’t work for women more than 80 kilograms (176 pounds). HRA Pharma changed its labels to warn patients after consulting with European regulators.