Experts have warned in an editorial published on bmj.com that although still rare, maternal deaths related to in vitro fertilisation (IVF) are a key indicator of risks to older women, those with multiple pregnancy and those with underlying disease.
Dr Susan Bewley and colleagues argue that serious adverse outcomes related to IVF treatment, such as ovarian hyperstimulation sydrome (a complication caused by some fertility drugs), should be systematically reported so that lessons can be learnt and appropriate action taken.
In 1991, the first published report of a maternal death related to IVF predicted that rates would rise with increasing use of assisted reproductive technologies as a result of pregnancies at an older age, multiple pregnancies, and pre-eclampsia.
A recent study from the Netherlands also showed convincingly that overall mortality in IVF pregnancies was higher than the maternal mortality rate in the general population in the Netherlands (there were about 42 mothers' deaths per 100,000 IVF pregnancies compared to 6 deaths per 100,000 pregnancies overall), a fact confirmed from results in the UK.
The last UK Confidential Enquiry into Maternal Death recorded four deaths directly related to IVF via ovarian hyperstimulation syndrome and three deaths related to multiple pregnancy after IVF.
Thus, more deaths were related to ovarian hyperstimulation syndrome than to abortion (two) despite many fewer IVF procedures (for example, there were 48,829 IVF cycles v 198,500 abortions in the UK in 2007), say the authors. They also warn that IVF associated maternal deaths may be underestimates as confidentiality restrictions under the Human Fertilisation Act preclude accurate data.
The global industry has operated on an assumption that women undergoing assisted reproduction are healthier than average thus ensuring safer pregnancies, but the maternal mortality figures suggests otherwise, they argue.
Even though IVF pregnancy in the UK is still very safe, they add, deaths may reflect a far greater burden of severe adverse morbidity.
They believe that better information about the risks of fertility treatment is needed, better identification of high risk women, and more single embryo transfer as the norm to prevent death and disability.
"More stringent attention to stimulation regimens, pre-conceptual care, and pregnancy management is needed so that maternal death and severe morbidity do not worsen further," they conclude.