Page 47 - Fertility in Women with Rheumatoid Arthritis Vruchtbaarheid van vrouwen met reumatoïde artritis

According to the national guideline (www.nvog.nl) unexplained subfertility was
recorded when fertility assessments did not show any plausible explanation for the
delay in the occurrence of a pregnancy.12
RA disease characteristics were drawn from the PARA study database,13 including date
of diagnosis, presence of rheumatoid factor (RF) or anti-citrullinated protein antibodies
(ACPA), and disease activity scores.13 Disease activity was scored using tender and
swollen joint counts in 28 joints, and serum C-reactive protein levels (DAS28-CRP-
3).14When available the preconceptional DAS28 of the designated PARA episode was 3 used, otherwise the rst trimester DAS28 of the same episode was used.3
Statistical analysis
To study potential selection bias, participants and non-participants were compared on obstetric history and disease characteristics as recorded during the last PARA episode that a subject had participated. Intergroup differences were calculated using the Student’s t-test and Mann-Whitney U-test for continuous outcome and the Chi- squared test or Fisher’s exact test for categorical outcome. Numbers of pregnancies, children and miscarriages were compared using a Mann-Whitney U-test.
The association of subfertility diagnoses with RA disease characteristics were studied using the Chi-squared test, Fisher’s exact test or Student’s t-test. Disease activity scores and periconceptional use of NSAIDs and prednisone from the rst subfertile episode in the PARA study were used. A two-sided p-value <0.05 was considered signi cant. Software used was IBM SPSS statistics version 21 and STATA/SE 14.1 (StataCorp).
RESULTS
Participants
Of the 260 questionnaires sent, 178 (68%) were completed and returned ( gure 1). Participants and non-participants were compared (table 1). Signi cantly more non-participants had not achieved a pregnancy during their most recent PARA study episode (37%) compared to participants (17%) (p=0.001). More often, non- participants were nulliparous at the end of their participation in the PARA study (24% versus 9%, p=0.002). There were more smokers among non-participants (22%) than in participants (6.7%) (p=0.001). Participants and non-participants did not differ signi cantly regarding age, education level, number of children they had already had, disease characteristics, or percentage of miscarriages or pregnancy complications.
Fertility in RA – fertility assessments
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