IVF linked to pregnancy complication risk in women

Women who have fertility treatments have a slightly higher risk of severe complications during pregnancy and delivery than those not undergoing treatment.

Viewed as an understudied topic in the field, a new study has highlighted the importance of identifying women at risk so negative outcomes can be avoided.

The study, conducted at McGill University in Montreal and St Michael's Hospital in Toronto, Canada, compared 11,546 women in Ontario who had received fertility treatments with 47,553 who received no treatment, between 2006 and 2012. The treatments recorded included ovulation induction, intrauterine insemination (IUI) and IVF with or without intracytoplasmic sperm injection (ICSI).

'We found that 30.8 per 1000 of the women in our study, who received an infertility treatment, experienced a severe pregnancy complication,' said Dr Natalie Dayan, who led the study.

This compared with 22.2 per 1000 experiencing a severe complication in the untreated group, who were the same age and had similar characteristics. Complications included bleeding, serious infections, intensive care admissions and, in rarer cases, death.

'Whether specific components of treatment using in vitro fertilisation, such as the dose of ovarian hyperstimulation or fresh versus frozen embryo transfer, contribute to these complications, or whether the increased risk is a reflection of a typical woman who requires or chooses in vitro fertilisation, remains to be determined,' the authors acknowledged.

Typically, women who have had fertility treatments are older, are first-time mothers or may be expecting twins (see BioNews 660) so their pregnancies are already high risk.

Similar studies in the USA also found a two-fold increase in the risk of severe complications in women who had undergone fertility treatment. However, the types of treatments used were not identified.

'IVF or other assisted reproductive technologies have been shown in several previous studies to be associated with severe pregnancy complications – however, as the authors of this paper note, this increase in pregnancy complications is most likely to be a reflection of underlying maternal health conditions rather than the IVF itself,' said Professor Marian Knight at the University of Oxford, who was not involved in the study.

The research, published in the Canadian Medical Association Journal, also revealed that the likelihood of a woman experiencing three or more severe maternal morbidity complications increased with IVF, but not with non-invasive procedures such as IUI.

'It is important to remember that the absolute number of women who develop these complications remains quite small,' said Dr Dayan. 'Meaning that for the vast majority of women or couples who cannot conceive naturally, this treatment is a very safe and effective method of becoming pregnant and having a child.'