Introduction Multiple births are high risk and remain a major complication for those undergoing assisted reproductive therapy (ART). In Ireland, more than one embryo is replaced during IVF treatment, leading to multiple births and increased socioeconomic costs.

Aim To determine the incidence and outcome of multiple births in the Rotunda Hospital in recent years. Furthermore, to compare the outcomes of those following ART (IVF, ICSI and IUI) with those conceived naturally.

Methods A retrospective audit was carried out of all liveborn multiple births greater than 500 g in the Rotunda Hospital between January 1st 2007 and December 31st 2007. Data was collected from the hospital information system, the Vermont Oxford Network and medical records. Information collected included whether the baby was born as a result of ART or not, NICU admission, birth weight.

Results 405 babies were born of multiple pregnancies, 119 of these (∼29.4%) were a result of ART. 160/405 (39.5%) of multiples required NICU admission versus 863/8000 (10.7%) of singletons required NICU admission. 49/119 (∼41%) of ART multiples were admitted versus 109/279 (∼39%) of non-ART multiples, data is not available currently on the remaining 2 admissions. Multiple births accounted for 39 (31.4%) of the 124 liveborn babies ⩽1500 g.

Conclusion Over a third of our multiples born ⩽1500 g are a product of ART. Elective single embryo transfer can significantly decrease multiple pregnancies associated with IVF. This has become standard practice in subgroups of women undergoing IVF in some European countries and should be considered in Ireland.