A retrospective audit was conducted at the Rotunda hospital, Dublin to assess the incidence of partial molar pregnancies and complete molar pregnancies over a 10-year period from the 1st of January 1997 to 31 of December 2006. Methods Records from the pathology department were accessed for the number of molar pregnancies from 1997 to 2006. Each pathology result was then retrieved to differentiate between complete moles and partial moles. The annual reports published by the hospital were used to obtain the number of deliveries and live births per year. Results The incidence of partial molar pregnancies at the Rotunda Hospital from 1997 to 2006 was 1 in 328 live births. The incidence of complete molar pregnancies from 1997 to 2006 was 1 in 1105 live births. The incidence of a molar pregnancy in the study period was 1:253. Conclusion The incidence of a molar pregnancy was estimated to be 1: 512 in 1993 and was 1: 253 in this study, indicating a significant rise. The incidence of complete and partial molar pregnancies has also doubled. The Rotunda hospital caters to a large proportion of Dublin's noncaucasian population which might account for an increase. But it is still possible that there is an over diagnosis of cases as diagnosis is only by histology and flow cytometry is not routinely performed in all cases.