O04 Fetal Outcome following Dydrogesterone Exposure in Pregnancy

BackgroundThe progestin dydrogesterone (DYD) is widely used for threatened and recurrent miscarriages, as well as for dysfunctional bleeding, infertility and other obstetric and gynecological indications. While its apparent efficacy has been compared to other progestins, its fetal safety has not been investigated.ObjectivesTo follow up fetal outcome after gestational exposure to DYD.Patients and methodsUsing a 2.5 million patients database, we compared congenital malformations among babies exposed in uteroto DYD between 1999 and 2016, to a control group not receiving this medication. We adjusted for concomitant exposure to in vitrofertilization (IVF) and to other forms of assisted reproductive technology (ART).ResultsThere were 8508 children exposed in uteoto DYD (4417 males, 4091 females) out of 777,422 live births. After excluding cases with concomitant exposure to IVF and other forms of ART, DYD was associated with increased risk for hypospadias [OR 1.28(95% confidence interval 1.06–1.55)], overall cardiovascular malformations [OR 1.18 (1.06–1.33)], spina bifida [OR 2.29(1.32–3.97] and hydrpcephalus [OR 2.04(1.28–3.25]. In additional analysis, including also those exposed to IVF and other forms of ART, there was also increased risk for cryptorchidism [1.37(1.19–1.58)] and congenital dislocation of the hip [OR 1.58(1.42–1.78)].ConclusionsDYD confers teratogenic effects after exposure to the recommended doses in pregnant women. Some of these adverse fetal effects are further augmented by concomitant use of IVF and other forms of ART. These independent teratogenic effects may have important implication for the child and family.Disclosure(s)Nothing to disclose