Background: In rheumatic diseases, specifically in chronic inflammatory arthritis (IA), there are no data about the effectiveness of LDA in preventing pregnancy complications.

Objectives: To assess the potential benefit of LDA administration during pregnancy to prevent adverse pregnancy outcomes (APO) in IA.

To compare pregnancy outcomes in IA pregnancies treated during pregnancy with LDA with those untreated.

Methods: Italian P-RHEUM.it register is designed as a nationwide, web-based longitudinal observational cohort study collecting data on pregnancies in inflammatory rheumatic diseases. At baseline, socio-demographic parameters, obstetric history, comorbidities and clinical/laboratoristic characteristics are registered. During pregnancy, the course of maternal disease, medications, development of fetus and complications are collected for each trimester.

Results: From May 2018 to May 2020, 349 patients were enrolled. Forty-five patients with IA had completed their pregnancy with known outcome (20 Rheumatoid Arthritis, 10 Psoriatic Arthritis, 6 Ankylosing spondylitis, 5 Juvenile Idiopathic Arthritis, 4 Undifferentiated Arthritis): 13 (28.89%) treated with LDA during pregnancy and 32 (71.11%) without LDA prophylaxis. LDA was used with a higher frequency in women with previous APO, anti-phospholipid positivity and on biological DMARDs even if it’s not statistically significant (Table 1). All the LDA-treated women had a live-birth rate of 100%, whereas among women not treated with LDA the live birth rate was of 84.4% with 27 live-birth pregnancies, 3 early miscarriages, 1 fetal loss and 1 stillbirth observed. There were no significant differences between the LDA and the not LDA groups regarding pregnancy/peripartum obstetric complications (p=0.14), although less adverse pregnancy/peripartum outcomes were registered in LDA patients’ group (Table 1).

Conclusion: The preliminary data of this prospective cohort study show that LDA improve pregnancy outcome in IA even if women treated with LDA had more risk factors for APO. The extension of this cohort will allow us to further investigate these important results.

References: [1]Roberge S, et al. AmJObstetGynecol.2017;216:110-120.e6.

[2]Andreoli L et al. Annals of the Rheumatic Diseases 2017;76: 476–85.

[3]Sammaritano L et al. Arthritis & Rheumatology 2020; 72: 529–56.

Acknowledgements: I would like to acknowledge the Epidemiology Unit of the Italian Society for Rheumatology and the Investigators of the Italian Registry.

Disclosure of Interests: None declared