BackgroundThe parity seems to decrease the risk of auto-immune diseases like Rheumatoid arthritis (RA). The risk reduction appeared when the parity number reached two [1]. The activity of RA improved during pregnancy and flares postpartum, but the relationship of parity to RA prognosis is unclear. The impact of childbirth on disease activity is less studied.ObjectivesWe aimed to investigate the impact of parity on rheumatoid arthritis activity.MethodsWe conducted a retrospective study including patients fulfilling the American Congress Of Rheumatology / European League Against Rheumatism (ACR EULAR) 2010 criteria.We collected epidemiological, clinical, biological (C-reactive protein: CRP, erythrocyte sedimentation rate (ESR), immunological status (rheumatoid factor RF and anti-citrullinated protein/peptide antibody ACPA), and disease activity index (The Disease Activity Score 28 DAS 28). We divided our patients into two groups: group (G1): the nulliparous women; group 2 (G2): women who gave birth.ResultsNinety-two patients were enrolled. There were 14 men and 78 women. The mean age was 59.56 ± 11.7 years. The mean disease duration was 9.32 ± 8.22 years. Among 78 women, we found 50 patients with parity. The main swollen joint was 3.34 ± 3.6 in G2 versus 4.44 ± 4.04 in G1 (p=0.94). The mean painful joints were 6.74 ± 5.12 and 9 ± 9.19 (p=0.28), respectively. However, the inflammatory syndrome is higher among women in G2. The mean CRP level was 15.1 mg/l, and the mean ESR was 37.7 mm. In G1, the RF and ACPA were 131 UI/l and 281 UI/l, respectively compared with 568 UI/L and 315UI/l, respectively in G2.A significant difference was noted in the DAS28-CRP between the two groups (G2: 4.18 ±1.23 versus G1: 4.49 ± 2.5, p=0.04).However, no association was found between parity and disease activity using the DAS28-ESR.ConclusionOur study showed that parity could have a protective effect on disease activity. It seems to be associated with a lower joint count and a lower rate of RF and ACPA. However, more studies are necessary to conclude these issues.References[1]Chen WMY, Subesinghe S, Muller S, Hider SL, Mallen CD, Scott IC. The association between gravidity, parity and the risk of developing rheumatoid arthritis: A systematic review and meta-analysis. Semin Arthritis Rheum. avr 2020;50(2):252‑60.Disclosure of InterestsNone declared