Successful pregnancy after in vitro fertilization in an ABO-incompatible kidney transplant recipient receiving rituximab: a case report

BACKGROUND: Successful pregnancy outcomes after in vitro fertilization in kidney transplant recipients have been reported, but few cases of successful pregnancy after ABO-incompatible kidney transplantation have been described. Herein, we report on a successful pregnancy after in vitro fertilization in an ABO-incompatible kidney transplant recipient with rituximab, focusing on the changes in immunity. CASE PRESENTATION: A 35-year-old woman with end-stage kidney disease caused by IgA nephropathy was referred for kidney transplantation and successfully underwent an ABO-incompatible living-donor kidney transplant using rituximab from her 66-year-old father at the age of 36. Because she and her husband desired childbearing, they received fertility treatments, and embryo cryopreservation was performed before transplantation. Two years after the transplant, she desired pregnancy. Although immunoglobulin levels such as IgG, IgA and IgM had recovered to almost normal range, the peripheral CD19(+) cells and CD20(+) cells remained depleted. At 6 months after conversion from mycophenolate mofetil to azathioprine, frozen embryo transfer was performed during the hormone replacement cycle. At 37 weeks and 4 days gestation, a healthy baby girl weighing 2220 g was delivered by cesarean section for arrest of labor. There were no complications in both the recipient and her baby during the perinatal period. At 5 years after the transplant, the recipient has had no major complications including rejection or infection. CONCLUSIONS: It is possible for women receiving ABO-incompatible kidney transplantation with rituximab to successfully become pregnant and deliver a heathy baby after in vitro fertilization, if IgG levels recover to normal range despite depleted peripheral blood B cells.