Molar pregnancy, also known as gestational trophoblastic disease, is a condition that occurs when there is an abnormal growth of trophoblast cells, which normally develop into the placenta during pregnancy. This can lead to the formation of a tumor instead of a viable pregnancy.
There are two main types of molar pregnancy:
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Complete Molar Pregnancy: In this case, an absence of normal embryonic tissue occurs, and the placenta forms an abnormal growth of cysts. This happens when an egg with no genetic material (or only paternal genetic material) is fertilized, leading to a proliferation of placental cells but no viable embryo.
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Partial Molar Pregnancy: This involves the presence of some normal placental tissue alongside abnormal tissue. It occurs when two sperm fertilize one egg, resulting in a triploid set of chromosomes. While there may be some embryonic development, it is usually not viable.
Symptoms of a molar pregnancy can include abnormal vaginal bleeding, excessive nausea and vomiting, abdominal pain, and signs of preeclampsia. Diagnosis is typically made through ultrasound and elevated levels of human chorionic gonadotropin (hCG). Treatment usually involves the removal of the abnormal tissue from the uterus, and close monitoring of hCG levels is required after treatment to ensure that it has resolved completely.