After suction curettage for hydatidiform mole, which diagnostic test is used to monitor for persistent gestational trophoblastic disease?

• A. Human chorionic gonadotropin (hCG) levels.
• B. Ultrasound.
• C. Complete blood count.
• D. Serum glucose.

Answer: (A)

Serial quantitative hCG levels are used to monitor for persistent gestational trophoblastic disease because the trophoblastic tissue that may remain or spread continues to produce hCG. After suction curettage for hydatidiform mole, hCG should fall to undetectable; if the levels plateau or rise, that signals persistent disease and calls for further evaluation and treatment. This biomarker is preferred because it directly reflects trophoblastic activity over time, providing a sensitive measure of whether disease persists. Imaging like ultrasound can help identify retained tissue or metastases, but it doesn’t track disease activity as reliably as serial hCG measurements. Other tests such as CBC or serum glucose do not assess trophoblastic disease.