MedicalResearch.com Interview with:
Natalie Dayan MD MSc FRCPC
General Internal Medicine and Obstetric Medicine,
Clinician-Scientist, Research Institute
Centre for Outcomes Research and Evaluation (CORE)
McGill University Health Centre
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Infertility treatment is rising in use and has been linked with maternal and perinatal complications in pregnancy, but the extent to which it is associated with severe maternal morbidity (SMM), a composite outcome of public health importance, has been less well studied. In addition, whether the effect is due to treatment or to maternal factors is unclear.
We conducted a propensity matched cohort study in Ontario between 2006 and 2012. We included 11 546 women who had an infertility-treated pregnancy and a singleton live or stillborn delivery beyond 20 weeks. Each woman exposed to infertility treatment was then matched using a propensity score to approximately 5 untreated pregnancies (n=47 553) in order to address confounding by indication. Poisson regression revealed on overall 40% increase in the risk of a composite of SMM (one of 44 previously validated indicators using ICD-10CA codes and CCI procedure codes) (30.3 per 1000 births vs. 22.8 per 1000 births, adjusted relative risk 1.39, 95% CI 1.23-1.56). When stratified according to invasive (eg., IVF) and non-invasive treatments (eg. IUI or pharmacological ovulation induction), women who were treated with IVF had an elevated risk of having any severe maternal morbidity, and of having 3 or more SMM indicators (adjusted odds ratio 2.28, 95% CI 1.56 – 3.33), when compared with untreated women, whereas women who were treated with non-invasive treatments had no increase in these risks.