Pregnancy and childbirth in Takayasu arteritis in Japan: A nationwide retrospective study.

Objectives: This study aimed to understand the status quo of medical treatments of the primary disease and pregnancy outcomes in patients with Takayasu arteritis (TAK) and children's birth outcomes.

Methods: This study retrospectively enrolled patients with TAK who conceived after the disease onset and were managed at medical facilities participating in the Japan Research Committee of the Ministry of Health, Labor, and Welfare for Intractable Vasculitis.

Results: This study enrolled 51 cases and 68 pregnancies 2019-2021. Of these, 48 cases and 65 pregnancies (95.6%) resulted in delivery and live-born babies. The median age of diagnosis and delivery was 22 and 31, respectively. Preconception therapy included prednisolone (PSL) in 51 (78.5%, median 7.5 mg/day), immunosuppressants in 18 (27.7%), and biologics in 12 (18.5%) pregnancies. Six cases underwent surgical treatment before pregnancy. Medications during pregnancy included PSL in 48 (73.8%, median: 9 mg/day), immunosuppressants in 13 (20.0%), and biologics in 9 (13.8%) pregnancies. Enlargement of an aneurysm was reported in one pregnancy, which might be associated with increased circulating plasma volume. TAK relapsed in 4 (6.2%) and 8 (12.3%) pregnancies during pregnancy and after delivery, respectively. Additionally, 13/62 (20.9%) preterm infants and 17/59 (28.8%) low birth weight infants were observed, and none had serious postnatal abnormalities. Of the 51 confirmed infants, 42 (82.4%) were exclusively breastfed or mixed with formula.

Conclusion: Most pregnancies in TAK were manageable with PSL at ≤10 mg/day. Relapse during pregnancy and postpartum occurred in <20% of pregnancies.