Chansriniyom N.Dulyaphat W.Singhsnaeh A.Bumrungphuet S.Mahidol University2026-02-062026-02-062026-12-01BMC Pregnancy and Childbirth Vol.26 No.1 (2026)https://repository.li.mahidol.ac.th/handle/123456789/114615Background: Placental chorioangioma is the most common placental tumor. Giant chorioangioma may lead to poor pregnancy outcomes. Current management includes invasive and less invasive procedure such as amnioreduction, interstitial laser coagulation (ILC) and fetoscopic laser ablation. We reported a unique case with transient fetal hydrops after ILC and amnioreduction. However, patient could continue pregnancy until term gestation without maternal and neonatal complications. Case presentation: A 38-year-old, parous woman presented with abdominal distension at 22<sup>+6</sup> weeks of gestation (WG) and transabdominal ultrasound revealed a placental chorioangioma estimating 7.9x5.6x5.4 cm with polyhydramnios and peritumoral hypervascularization. Borderline fetal cardiomegaly, increased combined cardiac output, and slightly increased peak systolic velocity of the middle cerebral artery were also demonstrated. After extensive counseling, ILC together with amnioreduction was performed at 23 WG. The feeding vessel was completely occluded. Two days after procedure, the fetus developed holosystolic tricuspid regurgitation, starry sky liver and fetal hydrops (scalp edema, pericardial effusion, pleural effusion, and ascites). However, fetal hydrops and tricuspid regurgitation were resolved at 26 WG. The remaining pregnancy was unremarkable. Conclusions: Herein, we report the first case of transient hydrops fetalis that developed after successful treatment of a giant placental chorioangioma by ILC and amnioreduction.MedicineTransient hydrops fetalis after interstitial laser coagulation and amnioreduction for treating placental chorioangiomaArticleSCOPUS10.1186/s12884-025-08304-62-s2.0-1050276476891471239341327114