No Increased Risk for Adverse Pregnancy Outcomes With DMARD Exposure in JIA

No increased risk exists for major adverse outcomes in pregnancy among women with juvenile idiopathic arthritis (JIA) or with partners of men with JIA who were exposed to disease-modifying antirheumatic drugs (DMARDs), according to study results published in Rheumatology.

German researchers sought to investigate the courses and outcomes of pregnancies in women with JIA and the partners of men with JIA who had long-term or up-to-pregnancy exposure to DMARDs. Data were collected from the JIA registry Biologics in Pediatric Rheumatology, and the follow-up registry, Juvenile arthritis Methotrexate/Biologics long-term Observation (JuMBO), which are 2 ongoing, multicenter, prospective, observational cohort studies. Data from the patients’ disease status and therapy were collected at visits conducted every 6 months.

Of the 1300 patients enrolled in the JuMBO study, 223 pregnancies in 117 women and partners of 25 men with JIA were reported. Detailed information was available for 152 pregnancies (98 in women with JIA and 21 in partners of men with JIA). These patients (n=119) did not differ from the overall study population in relation to JIA category, age, disease duration, or DMARD treatment. However, these patients experienced later initiation of biologic DMARDs (bDMARDs), had a lower education level, and experienced a different JIA spectrum, including less frequent systemic arthritis and more frequent polyarticular course JIA.

Women with JIA were observed for a mean period of 8.4 years until conception. All the women were treated previously with DMARDs; 92% were treated with bDMARDs. Among 152 pregnancies, 67 occurred during exposure to DMARDs: 30 to bDMARDs only, 24 to bDMARDs plus conventional synthetic DMARDs (csDMARDs), and 13 to csDMARDs only. DMARD exposure was discontinued in patients a median of 7 weeks (interquartile range, 5.0-11.5 weeks) after conception.

Men with JIA undergoing DMARD treatment were observed for a mean period of 8.2 years until conception. In this population, a total of 26 (67%) pregnancies were exposed to DMARDs: 15 (39%) to bDMARDs only, 6 (15%) to bDMARDs plus csDMARDs, and 5 (13%) to csDMARDs only.

Among 191 pregnancies, 24 (12.6%) were electively terminated, and 138 (72%) resulted in a live birth. A total of 22 elective abortions were performed in women: 1 due to fetal malformation without drug exposure, 11 due to fear of fetal malformation, and 3 due to medical recommendations for tumor necrosis factor inhibitor treatment. A total of 25 (13.1%) pregnancies ended in miscarriage, 2 women experienced an ectopic pregnancy, and 2 mothers experienced stillbirths. Of 138 live births, 8 (5.8%) malformations were noted in the children; 5 (3.6%) were classified as major congenital anomalies.

Study limitations included potentially uncounted birth defects, the small number of cases, lack of considerations of other potential risk factors, absence of an age-appropriate control group, and a possible recall bias in interview data.

“Most women and men with JIA had successful pregnancy outcomes despite frequent exposure to DMARDs” the researchers concluded. “The study underlines that more information on the use of DMARDs in both women and men during the conception period is needed.”

Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

Drechsel P, Stüdemann K, Niewerth M, et al. Pregnancy outcomes in DMARD-exposed patients with juvenile idiopathic arthritis—results from a JIA biologic registry [published online August 14, 2019]. Rheumatology (Oxford). doi:10.1093/rheumatology/kez309