Background/Purpose: SpA is a severe chronic inflammatory disease, which affects quality of life and functional status. It frequently occurs in women of childbearing age. Active disease and TNFi discontinuation at early pregnancy were found to be risk factors for flares during pregnancy (1). The aim of this study was to compare disease activity during pregnancy in patients with or without biological DMARD (bDMARD) exposure at conception and during pregnancy and to assess pregnancy outcomes.

Methods: RHEKISS is a prospective longitudinal cohort study including patients with confirmed diagnose of inflammatory rheumatic disease. Pregnant patients are eligible to be enrolled until the 20^th week of gestation regardless of drug treatment. During observation, information on treatment, disease and pregnancy course, and outcome are collected from rheumatologists and patients. For this analysis, pregnancies of patients with SpA and a reported outcome since the beginning of the registry until June 8^th 2020 were selected and stratified into three groups according to their exposure to bDMARDs.

Results: Of 140 SpA pregnancies included, 74 (53%) were not exposed to bDMARDs at conception (group 1), 38 (27%) were exposed to bDMARDs at conception, but not during pregnancy (group 2) and 28 (20%) were continuously exposed to bDMARDs at conception and during pregnancy (group 3). The bDMARDs prescribed were Certolizumab in 50%, Adalimumab in 21%, Etanercept in 12%, Infliximab in 9%, Golimumab in 2 patients, Sekukinumab and Ustekinumab in one patient each. Baseline characteristics according to treatment exposure are shown in table 1. Frequency of flares was highest in group 2: 21%, 38%, and 39% of patients flared during the 1^st, 2^nd, and 3^rd trimester. These rates were 20%, 25%, and 21% in group 1 and 8%, 20%, and zero in group 3. The difference in flare rates was also mirrored in the course of mean physicians’ assessed global disease activity (fig. 1). Whereas patients in group 1 seemed to have a quite stable disease activity during pregnancy, those who were in group 2 had an increasing activity of disease during pregnancy with an even higher increase of disease activity after giving birth. Patients in group 3 had the lowest disease activity during the total observation period.

Of 137 singleton pregnancies, 130 (95%) ended in live birth. Two spontaneous abortions in group 1 occurred in the same patient in gestational week 10 and 7. The spontaneous abortions in group 2 and 3 occurred in different patients in gestational week 10 and 16 (group 2) and in week 9 and 11 (group 3). One pregnancy in group 1 was terminated in gestational week 22 due to suspected malformation. In one triple pregnancy, one baby was born alive and two aborted in week 13. All babies of the two twin pregnancies were born healthy.

Conclusion: SpA patients treated with bDMARDs at conception are not at higher risk for adverse pregnancy outcomes compared to those without bDMARD exposure. Furthermore, our results confirmed the findings of smaller studies that discontinuation of bDMARDs after conception is associated with increased disease activity during pregnancy and after birth and a higher risk of flares.

Table 1: Baseline characteristics; numbers are n (%) if not otherwise specified; * value at beginning of pregnancy: first 22 weeks after conception

Figure 1: Mean course of physicians’ assessed global disease activity

« Back to ACR Convergence 2021

ACR Meeting Abstracts - https://acrabstracts.org/abstract/disease-activity-and-outcome-in-pregnancies-of-patients-with-spa-data-from-the-german-pregnancy-register-rhekiss/