Hydatidiform Mole (Complete)
Overview
Plain-Language Overview
Hydatidiform mole (complete) is a rare pregnancy-related condition affecting the uterus, where abnormal tissue grows instead of a normal embryo. It occurs when fertilization results in an abnormal set of chromosomes, leading to the development of a mass of cysts rather than a healthy baby. This condition primarily impacts the reproductive system and can cause symptoms like vaginal bleeding, a uterus that is larger than expected for the pregnancy stage, and very high levels of the pregnancy hormone hCG. Because the tissue is abnormal, it cannot develop into a viable fetus and may cause complications if not treated. Early diagnosis and management are important to prevent further health problems.
Clinical Definition
Hydatidiform mole (complete) is a form of gestational trophoblastic disease characterized by abnormal proliferation of trophoblastic tissue with diffuse swelling of chorionic villi and absence of embryonic or fetal tissue. It typically results from fertilization of an empty ovum by a single sperm that duplicates its genome or by two sperm, leading to a diploid androgenetic karyotype (usually 46,XX). The condition is marked by excessive hCG production, which can cause symptoms such as hyperemesis gravidarum, uterine enlargement, and early-onset preeclampsia. Complete moles carry a risk of progression to invasive mole or choriocarcinoma, making early recognition and monitoring critical. Histologically, there is diffuse villous edema and circumferential trophoblastic hyperplasia without fetal parts. The diagnosis is clinically significant due to potential malignant transformation and the need for careful follow-up.