Does ulipristal acetate emergency contraception (ella®) interfere with implantation?

摘要: Abstract Background Ulipristal acetate (UPA) 30 mg (ella®, HRA-Pharma, Paris, France) acts as an emergency contraceptive (EC) by delaying ovulation. Because it is a selective progesterone receptor modulator, additional effect on interfering with implantation has been suggested. Objective This review discusses the evidence for, and against, anti-implantation of UPA-EC. Sources Primary research UPA, at relevant dose, endometrium, implantation, efficacy pregnancy outcome. Results UPA-EC does not appear to have direct embryo. Changes in endometrial histology are small consistent, varying among studies. While affects profile gene expression human findings vary between studies, clear that these changes affect receptivity or prevent implantation. UPA pharmacological concentrations any inhibitory embryo attachment vitro systems endometrium. more effective preventing than chance alone if used after ovulation increase miscarriage rates. Conclusions An highly unlikely dose for EC. Maintaining warning FDA-approved label “it may also work uterus” might deter some women from using EC, leaving them no option unwanted unprotected sexual intercourse.