In vitro fertilisation (IVF) is linked to an increased rate of relapse among women with multiple sclerosis (MS), suggests a small study published online in the Journal of Neurology Neurosurgery and Psychiatry.
Sex hormone therapy and pregnancy itself are known to affect the MS relapse rate, and women with the condition outnumber men by 3:1, suggesting that hormones may have a role in MS.
The authors therefore wanted to know if synthetic hormonal treatments used during assisted reproduction techniques might also have an impact.
They base their findings on 32 women with MS, who underwent IVF at 13 French university hospitals over a period of 11 years between the start of 1998 and the end of 2008.
Between them, the women received 70 cycles of IVF, 48 of which included gonadotrophin releasing hormone (GnRH) agonists, and 19 of which included GnRH antagonists. These are synthetic chemicals, which are designed to control the timing of the release of natural hormones needed to prompt the ovaries and womb to prepare for a pregnancy.
Compared with the three months before, and the 12 months before, IVF, women were significantly (60%) more likely to suffer a relapse in the three months afterwards. Twenty six relapses occurred in the three months after the 70 IVF procedures.
When the time frame was reduced to 2 months, the odds rose to 71%.
The increased risk of a relapse was associated with the use of GnRH agonists, rather than antagonists, and with IVF failure.
Forty nine IVF procedures failed to produce a pregnancy, and among these women the risk of relapse almost doubled in the three months after treatment compared with the three months preceding it.
The proportion of successful pregnancies was lower among those treated with GnRH antagonists(10%) than among those treated with GnRH agonists (40%).
The authors point out that the stress of IVF itself could heighten the risk of relapse, and so may explain some of the association found. But nevertheless, women with MS who undergo IVF should be advised that there is a possible increased risk of relapse, particularly if the treatment is unsuccessful, they say.