The risk of stillbirth, preterm birth, low birth weight and neonatal death is nearly twice as high for babies conceived by assisted reproductive therapies compared with naturally conceived babies, according to a recent study.

Researchers at the University's Robinson Institute performed a "comprehensive study" to find out serious risks of complications are likely to occur during assisted birth, such as in-vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), ovulation induction, and cryopreservation of embryos, according to a press release..

"Compared with spontaneous conceptions in couples with no record of infertility, singleton babies from assisted conception were almost twice as likely to be stillborn, more than twice as likely to be preterm, almost three times as likely to have very low birth weight, and twice as likely to die within the first 28 days of birth," Michael Davies, study leader and professor at the University of Adelaide's Robinson Institute, said in a statement.

For the study, researchers compared the outcomes of more than 300,000 births in South Australia over a 17-year period. This included more than 4300 births from assisted reproduction.

They found that Very low and low birth weight, very preterm and preterm birth, and neonatal death were markedly more common in births from IVF and, to a lesser degree, in births from ICS, Davies said. Frozen embryos were also associated with increased risk of macrosomia or big baby syndrome for IVF and ICSI babies.

Davies says the study confirms related work in Europe and Australia showing that infertility treatment is associated with adverse outcomes for newborn babies.

"More research is now urgently needed into longer term follow-up of those who have experienced comprehensive perinatal disadvantage," he said. "Our studies also need to be expanded to include more recent years of treatment, as the technology has been undergoing continual innovation, which may influence the associated risks."