Page 63 - Fertility in Women with Rheumatoid Arthritis Vruchtbaarheid van vrouwen met reumatoïde artritis

INTRODUCTION
Rheumatoid arthritis (RA) and female reproduction have been linked in the literature for decades. It has been shown that RA often attenuated during pregnancy, while disease flares occur during the postpartum period.1 Furthermore, fertility is often impaired in female RA patients and is associated with disease activity and treatment with antirheumatic drugs.2,3
However, with regard to the frequency of miscarriages in patients with RA, results
have varied greatly. Whereas some studies have not shown an increased miscarriage
rate in RA patients,4-6 others have demonstrated a signi cant increase in miscarriage
rates both before and after disease onset.3,7,8 Recently, a Norwegian birth registry
study showed a signi cantly higher risk of miscarriage in women with RA compared 4 to the general population.8 The risk of recurrent miscarriage does not seem to be
increased in RA, as no markedly increased numbers of miscarriages have been found in individual women.5,7
Miscarriages may be the result of disturbed inflammatory mechanisms. In humans, about one-half of embryo implantations do not result in a successful pregnancy. This may be attributed to not only genetic factors or metabolic abnormalities of the embryo but also to poor uterine receptivity.9 A successful implantation may be facilitated by local injury of the endometrium, and more speci cally, by an inflammatory reaction to such endometrial injury.9 Therefore, inflammation, as well as antiinflammatory treatment, may play a role during implantation and early pregnancy in women with chronic inflammatory conditions such as RA.
Since miscarriages in RA have thus far been retrospectively assessed, no detailed information on patients’ disease activity prior to conception has been reported. Moreover, reports on the preconception use of antirheumatic medications and rates of miscarriages may be biased. Therefore, the association between these factors and the occurrence of miscarriages in RA remains unclear. Miscarriages before the onset of RA are associated with more severe joint damage over time after diagnosis.10 What happens to RA disease activity during the months directly after a miscarriage is not known.
Within a nationwide prospective cohort on pregnancy in RA, we studied the occurrence of miscarriage in women with RA and its association with serologic ndings, disease activity, and periconceptional use of antirheumatic drugs. In addition, we assessed the course of RA after miscarriage and the occurrence of subsequent pregnancies.
Miscarriages in RA
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