Early molar pregnancy: experience in a large abortion service.

Background: With 1.1 million US women having first-trimester abortions annually, clinicians have an opportunity to diagnose molar pregnancy early. Early moles, however, may lack "classic" diagnostic hallmarks.

Study Design: This study aimed to assess the accuracy of the diagnosis of hydatidiform mole in women seeking abortion services at a large Planned Parenthood affiliate. We retrospectively identified women with a histopathologic diagnosis of mole from the affiliate's risk management database. The tissue specimens were reviewed by an expert independent pathologist and analyzed by flow cytometry and p57(KIP2) immunohistochemical staining to clarify the diagnosis.

Results: Of 21 patients who received an initial histopathologic diagnosis of mole, only six proved to have the condition. The interobserver correlation coefficient (kappa) for pathology examination was (-) 0.353. Overdiagnosis of partial moles was the most common error.

Conclusions: Improved, cost-effective strategies for detection of early moles would benefit patients and providers.