Introduction/Background Twin pregnancy with complete mole is a rare entity, with high risk and non-standardized management. This case allows us to share our experience regarding this entity.

Methodology We report the case of a twin pregnancy with complete mole managed in the gynaecology-obstetrics department of the Aziza Othmana hospital in Tunis in April 2022.

Results This is a 39 year old patient, chronically hypertensive, who consulted our emergency at 22 weeks of amenorrhea (WA) + 3 days for metrorrhagia. She was a nulliparous woman with a history of early spontaneous miscarriage and fetal death in utero at 6 months in relation with pre-eclampsia. Her 1st trimester ultrasound showed a single fetus with fine nuchal translucency and bilateral uterine artery notch. Her maternal 1st trimester serum markers revealed an elevated trisomy risk of 1/101 and a beta HCG level at 15.35 mom. Ultrasound on admission revealed a 21 (WA) fetus in severe oligohydramnios with a 65*58 mm heterogeneous honeycomb overlying placenta opposite the internal cervical os suggestive of partial mole. The patient presented with heavy metrorrhagia requiring a transfusion of 3 packed red blood cells and a caesarean section revealing a vesicular overlying placental mass and a fetus of 21 (WA), the end of the operation was uneventful with a blood loss of 500cc. The weekly bhcg levels kinetics were as follows: initial value 11768 mUI/L, at day 7 post operative 242 mUI/L with no image of retention, until it was negated in less than 8 weeks.

Conclusion This rare neoplastic pathology cannot be diagnosed by ultrasound or macroscopic examination of the placenta with certainty; only anatomopathological examination provides the diagnosis