Antisynthetase syndrome during pregnancy: a case of intrauterine fetal demise, successful subsequent pregnancy, and systematic review of maternal–fetal outcomes

Antisynthetase syndrome is a rare autoimmune disease characterized by inflammatory myopathy, interstitial lung disease, arthritis, and anti-aminoacyl-transfer RNA synthetase antibodies. Pregnancy in women with antisynthetase syndrome is uncommon, and data regarding maternal and fetal outcomes remain scarce. We report the case of a 26-year-old, gravida 3 para 1, who presented at 16 week gestation with facial edema, dyspnea, myalgias, progressive muscle weakness, arthralgias, and periorbital erythema. At 23 week gestation, she was admitted with severe muscle weakness and pelvic pain. Ultrasound examination revealed intrauterine fetal demise associated with fetal hydrops. Investigations demonstrated strongly positive anti-Jo-1 antibodies, interstitial lung disease on imaging, and restrictive ventilatory impairment on pulmonary function testing, leading to the diagnosis of antisynthetase syndrome with muscular and pulmonary involvement. Placental histopathology showed maternal and fetal vascular malperfusion with extensive fibrin deposition. High-dose corticosteroids followed by rituximab resulted in progressive clinical improvement. Several years later, while the disease was in complete remission under rituximab therapy, a subsequent pregnancy managed by a multidisciplinary team resulted in the delivery of a healthy infant without maternal complications. We additionally performed a systematic review according to PRISMA guidelines. Thirteen publications reporting fourteen pregnancies complicated by antisynthetase syndrome were identified. Adverse pregnancy outcomes were frequent, including intrauterine growth restriction, preterm delivery, and fetal loss, whereas only a minority of pregnancies resulted in term delivery of a healthy neonate. Antisynthetase syndrome during pregnancy is associated with significant maternal and fetal morbidity, particularly in the presence of active disease and interstitial lung involvement. This case highlights the potential role of disease control and multidisciplinary management in improving pregnancy outcomes and underscores the need for close obstetric, rheumatologic, and respiratory monitoring.