Gestational surrogacy in Australia 2004-2011: treatment, pregnancy and birth outcomes.

ABSTRACT

BACKGROUND: Information on gestational surrogacy arrangement and outcomes is limited in Australia. AIMS: This national population study investigates the epidemiology of gestational surrogacy arrangement in Australia treatment procedures, pregnancy and birth outcomes. MATERIALS AND METHODS: A retrospective study was conducted of 169 intended parents cycles and 388 gestational carrier cycles in Australia in 2004-2011. Demographics were compared between intended parents and gestational carrier cycles. Pregnancy and birth outcomes were compared by number of embryos transferred. RESULTS: Over half (54%) intended parents cycles were in women aged <35 years compared to 38% of gestational carrier cycles. About 77% of intended parents cycles were of nulliparous women compared to 29% of gestational carrier cycles. Of the 360 embryo transfer cycles, 91% had cryopreserved embryos transferred and 69% were single-embryo transfer (SET) cycles. The rates of clinical pregnancy and live delivery were 26% and 19%, respectively. There were no differences in rates of clinical pregnancy and live delivery between SET cycles (27% and 19%) and double-embryo transfer (DET) cycles (25% and 19%). Five of 22 deliveries following DET were twin deliveries compared to none of 48 deliveries following SET. There were 73 liveborn babies following gestational surrogacy treatment, including 9 liveborn twins. Of these, 22% (16) were preterm and 14% (10) were low birthweight. Preterm birth was 13% for liveborn babies following SET, lower than the 31% or liveborn babies following DET. CONCLUSIONS: To avoid adverse outcomes for both carriers and babies, SET should be advocated in all gestational surrogacy arrangements.