January 8, 2014

expert reaction to study suggesting higher risk of birth problems after fertility treatment

A study in PLOS ONE found children born after IVF treatment had a greater risk of birth complications. A before the headlines analysis accompanied this roundup. 

Alison Murdoch, Professor of Reproductive Medicine, Newcastle University, said

“This is bad science. They have taken a large set of data and undertaken multiple analyses. The patient subgroups selected indicates a lack of understanding of the clinical problem and the selection of outcomes is equally non-specific.  For instance, stillbirth has many origins. Thus the analyses have value but primarily as a hypothesis generating exercise. The data would then need much further analysis before any conclusions could be reached that would justify new headlines or new advice for patients. The headlines in the press release may reflect correct numbers from the analysis but they have not provided evidence that they are correct clinical conclusions.

 “There could, and probably will be, a lot of debate in the profession about this analysis but the immediate problem is how it will be headlined and the consequences. For the reassurance of patients, it might be better to consider their data in reverse i.e. if you are over 20 weeks pregnant after conceiving without fertility treatment, the chance of a live birth is 99.5% and after fertility treatment is 98.9%. If you decide not to have fertility treatment but are fortunate to get pregnant without help, then chance of a live birth is 97.6%.

 “The information that is most interesting in the paper is the poor obstetric outcome that is related to any history of subfertility.  That is not new data but it is very relevant to be aware of this when doing any comparisons of obstetrics outcome after fertility treatment.”

Sheena Lewis, Professor of Reproductive Medicine, Queen’s University Belfast said:

“We have known for some time that couples conceiving spontaneously after a period of infertility have poorer outcomes. This indicates that these problems may come from the disease rather than the fertility treatment.

“Also a very positive finding in this study is that the use of frozen embryos eliminates all the adverse outcomes following  ICSI. Freezing embryos is a routine procedure in fertility clinics and may be a useful option for those couples concerned about these findings.”

Professor Dagan Wells, University of Oxford, said:

“It is very important that patients are provided with useful information concerning the risks as well as the benefits of any medical interventions they might undertake so that they can make an informed decision about whether a given procedure is right for them. Although this study suggests that some adverse outcomes are higher in pregnancies conceived using IVF, it is important to understand that the overall risk of these problems remains low. As such, I doubt these findings will deter many infertile couples from using IVF.

“Perhaps the most striking finding is that rates of prematurity, low birth-weight and infant death were highest of all for couples who had a fertility problem but eventually succeeded in conceiving without the help of IVF. This suggests that the problems seen for babies born after IVF may be related to the patient’s infertility rather than the treatment itself. In fact, for couples with reduced fertility, IVF seemed to lessen these risks compared to natural conception. For example, couples with a fertility problem who conceived using IVF had a three-fold increase in the risk of low birth weight, but risks were considerably worse for patients who persevered with natural conception and eventually managed to conceive without medical intervention. The risk of low birth-weight for them was increased nine times compared to the general population.”

‘Perinatal outcomes by mode of assisted conception and sub-fertility in an Australian data linkage cohort’ by Marino et al. published in PLOS ONE on Wednesday 8th January.