Background Exogenous sexual steroids together with pregnancy have been shown to influence the risk of relapses in multiple sclerosis (MS). Treatments used during assisted reproductive techniques may consequently influence the short term evolution of MS by modifying the hormonal status of the patient. The objective of this study was to determine if there was an increased risk of developing exacerbations in women with MS after in vitro fertilisation (IVF).

Methods MS and IVF data were either automatically extracted from 13 French university hospital databases or obtained from referring neurologists. After matching databases, patient clinical files were systematically reviewed to collect information about MS and the treatments used for IVF. The association between IVF and the occurrence of MS relapses was analysed in detail using univariate and multivariate statistical tests.

Findings During the 11 year study period, 32 women with MS had undergone 70 IVF treatments, 48 using gonadotrophin releasing hormone (GnRH) agonists and 19 using GnRH antagonists. A significant increase in the annualised relapse rate (ARR) was observed during the 3 month period following IVF (mean ARR 1.60, median ARR 0) compared with the same period just before IVF (mean ARR 0.80, median ARR 0) and to a control period 1 year before IVF (mean ARR 0.68, median ARR 0). The significant increase in relapses was associated with the use of GnRH agonists (Wilcoxon paired test, p=0.025) as well as IVF failure (Wilcoxon paired test, p=0.019).

Interpretation An increased relapse rate was observed in this study after IVF in patients with MS and may be partly related both to IVF failure and the use of GnRH agonists.