Hydatidiform Molar Pregnancy occurs when the cells that are supposed to form the placenta grow abnormally. In a “complete mole” or CHM no normal fetal tissue is present. In a “partial mole” or PHM fetal tissue is identified. There is also an invasive mole, a coexistent live fetal pole with mole and a malignant form, coriocarcinoma. This blog will focus on a case that was diagnosed as a CHM. Routinely, these patients will present with abnormally high serum hCG levels and an enlarged uterus. A recent study suggests that only 60% of patients will have vaginal bleeding. They can also present with anemia, hyperemesis, hypertension, and ovarian theca-lutein cysts.
Most sonographers are aware of the classic “cluster of grapes” appearance of the uterus with a molar pregnancy. Like these 2 images from the web:
Here is a case with an atypical ultrasound appearance. A 25 year old female came in for a routine early ultrasound exam to establish dating and viability. She presented with no symptoms. By her last menstrual period she should have been around 8 weeks 6 days along. She had no blood work yet, only a positive urine test.
Upon evaluating the pelvis transabdominally the uterus measured large, greater than 15 cm. Transvaginally, multiple large cysts were identified. A large hyperechoic solid mass was seen encompassing the endometrium. No fetal pole, yolk sac or true gestation sac was identified. The ovaries appeared normal without evidence of a theca-lutein cyst.
An immediate serum hCG was ordered and was 160,252. Two days later a D & C was performed with suction. Serial serum hCG labs where performed and dropped each week (4660, 1655, 135, 10) until they reached 0 which took about 6 weeks. The patient has recovered and is planning on conceiving again this summer.