Serum β-hCG Regression Pattern and Time to Normalization in High-Risk Complete Hydatidiform Mole Treated with Prophylactic Chemotherapy

Abstract

Background: There is a significant risk of progression to gestational trophoblastic neoplasia in complete hydatidiform mole, and many South Asian centers use prophylactic chemotherapy to minimize this risk. The pattern of serial serum β-hCG regression in this practice, however, is not well described.

Objectives: This study aimed to describe the pattern of regression and the time to normalization of serum β-hCG levels in women with high-risk complete hydatidiform mole (CHM) who received prophylactic chemotherapy.

Methods: This prospective observational study of 41 women with ultrasonographically or histopathologically confirmed high-risk complete hydatidiform mole who were conducted at Mugda Medical College & Hospital, Dhaka, Bangladesh from January 2025 to December 2025. Serum β-hCG was determined at baseline, around 48 hours after evacuation, and at serial follow-up visits until normalization. Data were entered and analyzed on SPSS version 26.

Results: The mean age was 25.02±7.08 years, and 56.1% of patients were multigravida. Baseline β-hCG was ≥100,000 mIU/mL in 90.2% of patients (median 170,250 mIU/mL). In 75.6% of cases, prophylactic chemotherapy was used, and none of the patients had toxicity related to the treatment. All 41 patients (100%) had a progressive decline in serum β-hCG levels and reached normalization, with a mean time to normalization of 105.71 ± 38.16 days (median, 97; IQR, 90–119). The time to normalization was significantly shorter in those with histopathologically confirmed complete mole than in those with unspecified/unavailable histopathology (84 days vs 98 days, p=0.043), but was not significantly associated with receipt of chemotherapy or baseline β-hCG category.

Conclusion: Prophylactic chemotherapy in high-risk complete hydatidiform mole was found to be associated with complete normalization of β-hCG in all patients without any toxicity, thus suggesting that serial β-hCG monitoring is a reliable, inexpensive method for monitoring regression and follow-up in resource-limited areas.

CME J 2026; 5(1): 46-53