TOPLINE:

Women with spondyloarthritis (SpA) had higher odds of small-for-gestational-age births than women in the general population. Rates of other adverse pregnancy outcomes such as preterm birth and caesarean delivery were similar to those in the general population.

METHODOLOGY:

• Researchers evaluated the prevalence of adverse pregnancy outcomes among women with SpA identified from a multicenter prospective observational study in France.
• A total of 135 pregnancies in 124 women with SpA (mean age at pregnancy, 32.1 years; 51.1% cases of axial SpA) from December 2015 to June 2021 were analyzed. Of these, 128 pregnancies were matched with 512 control pregnancies from the general population, identified from 2016 and 2021 surveys, based on age, parity, and other factors.
• Data collection encompassed maternal demographics, disease activity (assessed using the Bath Ankylosing Spondylitis Disease Activity Index), treatments, and pregnancy outcomes, with follow-up as long as 12 months postpartum.
• The pregnancy outcomes assessed included fetal loss, small for gestational age, low birth weight, macrosomia, preterm birth, and neonatal transfer to ICUs.
• Maternal outcomes included gestational diabetes, hypertensive disorders, and severe postpartum hemorrhage; risk factors for adverse pregnancy outcomes, focusing on small-for-gestational-age births, were identified.

TAKEAWAY:

• Of the 135 pregnancies, 92.6% resulted in live births; six newborns were reported to have congenital malformations, including major issues such as agenesis of the corpus callosum, minor ones such as hydronephrosis and a rare genetic syndrome.
• Women with SpA had a significantly higher rate of small-for-gestational-age births ≤ 10th percentile (17.4%) than the general population (9.8%; odds ratio [OR], 1.94; 95% CI, 1.09-3.39) and ≤ third percentile (OR, 2.35; 95% CI, 1.02-5.49).
• Rates of other adverse pregnancy outcomes, such as preterm birth and caesarean delivery, were not significantly different between women with SpA and the general population.
• No significant association was found between small for gestational age and potential predictors such as maternal age, disease duration, or medication use during pregnancy.

IN PRACTICE:

“The pregnancies included in our study, which reflect the current clinical management of SpA, with more than half of the women treated with biologics, support the fact that adverse pregnancy outcomes rates are now close to those of the general population, except [small for gestational age],” the authors wrote. “These results provide very reassuring data for patients and physicians and should help the counselling and management of pregnancy in women with SpA,” they added.

SOURCE:

This study was led by Sabrina Hamroun, MD, NOVO Hospital in Pontoise, France, and Grégoire Martin de Frémont, MD, who conducted the research while at Kremlin-Bicêtre University Hospital, Le Kremlin-Bicêtre, France, but now is a PhD student at the Karolinska Institutet, Stockholm, Sweden. It was published online on November 14, 2025, in Annals of the Rheumatic Diseases.

LIMITATIONS:

The study’s statistical power was limited by the relatively small number of patients, which restricted subgroup analyses on different forms of SpA. The selection of participants from tertiary centers could introduce selection bias.

DISCLOSURES:

The multicenter prospective observational study received funding from various patient associations, the AFM-Telethon, the French Society of Internal Medicine, the French Society of Rheumatology, and other sources. Some authors reported receiving grants, honoraria, consulting fees, and having other ties with several pharmaceutical companies, including UCB, AbbVie, Amgen, and Pfizer.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.