Axial spondyloarthritis and breastfeeding: a prospective study.

Background: There is sparse literature on the topic of breastfeeding in women with axial spondyloarthritis (axSpA). Our aim was to obtain more knowledge about variables affecting breastfeeding for women with axSpA.

Methods: This prospective study used data from the nationwide quality register RevNatus, which collects pregnancy-related data in women with inflammatory rheumatic diseases from Norwegian outpatient clinics in rheumatology. Data were collected during January 2016 to August 2023, reporting on 436 pregnancies in 363 patients with axSpA. The study eventually included 417 births in 350 women. Breastfeeding and non-breastfeeding women were compared at six weeks, six and twelve months postpartum. We compared the groups regarding demographic and obstetric data, neonatal outcome, disease characteristics, medical treatment and self-reported data on pain, fatigue and disease burden. Information on breastfeeding was registered at least once during the follow-up postpartum. Disease activity was measured by Ankylosing Spondyloarthritis Disease Activity Index-CRP (ASDAS-CRP) and Bath Ankylosing Disease Activity Index (BASDAI).

Results: The proportion of patients breastfeeding at the postpartum follow ups was 86% (347 women) at six weeks, 70% (221 women) at six months, and 38% (104 women) at twelve months, respectively. A larger proportion of the non-breastfeeding group had delivered with caesarean section (C-section), 24 of 59 (41%) non-breastfeeding vs 70 of 347 (20%) breastfeeding women. ASDAS-CRP was higher for the non-breastfeeding group at six weeks (2.6 vs 2.2) and at six months (2.6 vs 2.1), and BASDAI was higher for the same group at six months (4.1 vs 3.2). CRP (mg/L) was significantly higher among the non-breastfeeding at six months (5.3 vs 3.3). VAS pain scores were higher for the non-breastfeeding group at six weeks (41.0 vs 31.6) and six months (43.9 vs 31.0). VAS fatigue was higher for the same group at six months (46.8 vs 37.8).

Conclusion: Our results suggest that particular attention should be given regarding breastfeeding to women with active inflammatory disease and those who have undergone C-section.