Successful Spontaneous Twin Pregnancy Following Bone Marrow Transplant and Gastric Cancer Surgery: A Case Report

Unusual clinical course Background:Pregnancy following bone marrow transplantation (BMT) and treatment for gastric cancer is rare because of gonadotoxic conditioning regimens, major abdominal surgery, and the overall burden of chronic illness.Reports of spontaneous twin pregnancy after both allogeneic BMT and gastrectomy are exceptionally uncommon. Case Report:We describe the case of a 22-year-old woman with a history of severe aplastic anemia treated with allogeneic BMT (February 2022), who subsequently underwent subtotal gastrectomy for gastric adenocarcinoma (May 2022).She conceived spontaneously with a dichorionic-diamniotic twin pregnancy in 2024, several years after completion of oncologic treatment, without fertility preservation.Early pregnancy was uneventful, with reassuring serial ultrasound scans and normal fetal growth.In the second trimester, she developed extensive lowerlimb deep vein thrombosis (superficial femoral vein thrombosis confirmed by compression Doppler ultrasound) requiring therapeutic anticoagulation with enoxaparin 1 mg/kg twice daily, followed by obstructive uropathy due to ureteric compression that necessitated double-J stent insertion.Maternal nutritional status and weight gain were closely monitored with serial laboratory assessment (including hemoglobin, ferritin/iron indices, vitamin B12, folate, and albumin) given her prior gastrectomy.Multidisciplinary care involving maternal-fetal medicine, hematology, oncology, urology, and anesthesia teams guided surveillance and delivery planning.At 35+6 weeks of gestation, an elective cesarean section was performed because of dichorionic twin gestation, prior major abdominal surgery, and ongoing therapeutic anticoagulation requiring coordinated perioperative planning.Two live infants with appropriate birthweights and good Apgar scores were delivered, and the postoperative course was uncomplicated for both mother and neonates. Conclusions:This case illustrates that successful twin pregnancy is possible after BMT and gastric cancer surgery when individualized, multidisciplinary care and careful thromboembolic and urological surveillance are provided.It also supports the need for structured preconception counseling, fertility follow-up, and pragmatic monitoring protocols for high-risk pregnancies in young cancer and transplant survivors.