Recurrent GTD and GTD coexisting with normal twin pregnancy

Area of Science:

• Reproductive Medicine
• Genetics
• Obstetrics

Background:

• Hydatidiform mole (HM) affects 1 in 1000 pregnancies, with a 1% recurrence risk, higher in complete HM (CHM).
• A subset of patients experiences recurrent pregnancy loss due to familial recurrent biparental HM syndrome, often caused by maternal genetic mutations in imprinting genes (e.g., NALP7, KHDC3L).
• Twin pregnancies with HM, predominantly CHM, occur in 1 in 50,000 cases and carry substantial risks.

Purpose of the Study:

• To review the genetic basis of recurrent hydatidiform mole.
• To discuss management strategies for twin pregnancies complicated by hydatidiform mole.
• To differentiate HM from conditions with similar ultrasound presentations.

Main Methods:

• Literature review focusing on genetic mutations, recurrence risks, and management of hydatidiform mole.
• Analysis of outcomes in twin pregnancies with co-existing hydatidiform mole.
• Comparison of histological and genetic features of HM with mimicking conditions.

Main Results:

• Maternal genetic mutations in NALP7 and KHDC3L are key factors in familial recurrent HM, with oocyte donation being an effective treatment.
• Twin pregnancies with HM have increased risks of complications but can result in a liveborn infant in about one-third of conservatively managed cases.
• Persistent GTD risk in twin HM pregnancies is comparable to singleton CHM; conditions like CHM mosaicism and placental mesenchymal dysplasia mimic HM but have distinct features.

Conclusions:

• Genetic counseling and oocyte donation are crucial for patients with familial recurrent HM.
• Conservative management of twin pregnancies with HM can lead to successful livebirths, despite associated risks.
• Accurate diagnosis differentiating HM from mimics is essential for appropriate patient management.