Prenatal Diagnosis of Twin Pregnancies with Complete Hydatidiform Mole and Coexistent Normal Fetus: A Series of 13 Cases

Abstract

Aim: The study aimed to describe prenatal diagnosis and the outcome of complete hydatidiform mole and coexistent normal fetus (CHMCF). Methods: This was a retrospective case series of 13 patients with CHMCF. Prenatal diagnosis, outcome and development of gestational trophoblastic neoplasia (GTN) were reviewed. Results: Ultrasound diagnosis was carried out in 12 of 13 cases at 17 ± 2.7 weeks of gestation (mean ± SD). Six patients showed abnormalities suggestive of subchorionic hematoma on first trimester ultrasonography (US). Prenatal invasive procedures were performed in 8 of 13 cases (62%). Two women decided to terminate their pregnancies. Four ended in late miscarriages (36%, 4 of 11) between 13 and 21 weeks, and early neonatal death occurred in 1 case (9%, 1 of 11); 5 women delivered a live baby with a mean gestational age of 31 weeks (range 26-37 weeks) with an overall neonatal survival of 45% (5 of 11). GTN occurred in 31% of cases (4 of 13). Conclusions: The first trimester US features of CHMCF are not well-documented. Our series showed that abnormalities of CHMCF could be misdiagnosed as subchorionic hematoma in the early first trimester. When CHMCF is confirmed by expert US, prenatal invasive procedures should be carefully evaluated depending on the associated US findings and exhaustive counseling should be performed.

A Pictorial Ultrasound Essay of Gestational Trophoblastic Disease

“…Placental chorioangioma is a vascularized mass located on the fetal placental surface with different echogenicity than the rest of the placenta . Also, a CHMCF, especially in the first trimester, can be mistaken for a subchorionic hematoma because of common US features . β‐Human chorionic gonadotropin levels, fetal DNA testing, or, if necessary, invasive prenatal diagnosis for determination of fetal karyotype can aid decision making in difficult cases .…”

“…5 Ultrasound features of a CHMCF consist of a complex cystic pattern with vacuolar tissue adjacent to a normal placenta and a structurally normal fetus. 34 The differential diagnosis of a CHMCF includes a PHM, placental mesenchymal dysplasia, placental chorioangioma, and subchorionic hematoma. The distinction between a CHMCF and a PHM is usually based on US features, as the triploid fetus of a PHM carries several structural anomalies and rarely survives beyond the first trimester.…”

“…35 Also, a CHMCF, especially in the first trimester, can be mistaken for a subchorionic hematoma because of common US features. 34 β-Human chorionic gonadotropin levels, fetal DNA testing, or, if necessary, invasive prenatal diagnosis for determination of fetal karyotype can aid decision making in difficult cases. 19,20,22,25 More recently, the development of circulating fetal DNA testing from maternal blood holds promise for a noninvasive aid to the diagnosis of twin pregnancies comprising a CHM and a healthy cotwin ( Figure 3).…”

Twin pregnancy with a partial hydatidiform mole and a coexistent live fetus. Diagnostic and therapeutic dilemmas. A case report and the review of literature

“…The coexistence of a hydatidiform mole with a normal fetus is extremely rare with an incidence of 1/20 000 to 1/100,000 pregnancies [1][2][3][4]. In most cases, this is a complete hydatidiform mole (CHM).…”

“…Partial hydatidiform mole (PHM) coexistent with a live fetus, in two separate amniotic sacs, is even less frequent since a partial molar pregnancy usually ends in early intrauterine death and miscarriage [5]. Diagnosis is by ultrasound, mostly in the second trimester, usually between 12 and 15 weeks [1,3]. Even with advanced ultrasound technologies, correct diagnosis is made in approximately 68% of cases and first-trimester diagnoses are rare.…”