From the Guidelines
A molar pregnancy requires immediate treatment, typically involving surgical evacuation of the uterus through dilation and curettage (D&C), followed by close monitoring of human chorionic gonadotropin (hCG) levels to prevent the development of gestational trophoblastic neoplasia (GTN), a form of cancer 1.
Diagnosis and Treatment
The safest method of evacuation is suction dilation and curettage (D&C) under ultrasound control to ensure adequate emptying of uterine contents and to avoid uterine perforation 1.
- Histological examination of every termination is essential to achieve a correct diagnosis, as false positive and negative rates are high with ultrasound, especially for partial molar pregnancies 1.
- All women with a diagnosis of molar pregnancy require careful hCG monitoring to look for the recurrence of disease, suggesting malignant change indicated by a plateaued or rising hCG on three and two consecutive samples, respectively 1.
Monitoring and Follow-up
- Close monitoring of hCG levels is essential, with blood tests initially weekly, then monthly for 6-12 months 1.
- Patients should avoid becoming pregnant during this monitoring period, as approximately 15-20% of complete molar pregnancies can develop into GTN 1.
Symptoms and Risk Factors
- Symptoms of molar pregnancy include vaginal bleeding, severe nausea and vomiting, high blood pressure, and a uterus larger than expected for gestational age 1.
- The condition results from abnormal fertilization, with complete molar pregnancies resulting from an empty egg fertilized by one or two sperm, and partial molar pregnancies resulting from an egg fertilized by two sperm, resulting in 69 chromosomes instead of the normal 46 1.
Prognosis and Future Pregnancies
- After treatment, most women can go on to have normal pregnancies, though they have a slightly increased risk of developing another molar pregnancy in the future 1.
- Cure rates for gestational trophoblastic neoplasia (GTN) are approaching 100%, and treatment typically allows for fertility preservation 1.
From the Research
Definition and Diagnosis of Molar Pregnancy
- A molar pregnancy is a type of gestational trophoblastic disease (GTD) characterized by an abnormal growth of trophoblast cells in the uterus 2, 3, 4.
- It can be classified into two main types: complete molar pregnancy (CMP) and partial molar pregnancy (PMP) 3, 4.
Treatment and Follow-up of Molar Pregnancy
- The standard treatment for molar pregnancy is uterine evacuation, which involves removing the abnormal tissue from the uterus 2, 3.
- After evacuation, patients are typically monitored with serial beta-human chorionic gonadotropin (β-hCG) levels to ensure that the levels return to normal 2, 3, 4.
- The risk of developing gestational trophoblastic neoplasia (GTN) is higher in patients with elevated β-hCG levels after evacuation 3, 4.
- A study found that an β-hCG level >199 mIU/mL in the third through eighth week following molar evacuation was associated with at least a 35% risk of GTN 4.
Special Considerations
- Uterine artery embolization (UAE) may be performed in cases of acute bleeding or arteriovenous malformation, but it can cause a transient increase in β-hCG levels, which can be benign 2.
- The duration of β-hCG monitoring after evacuation may be shortened in patients who achieve a spontaneous negative β-hCG, as the risk of GTN is negligible in these cases 3.