Review of the Course and Outcome of 100 Pregnancies in 84 Women Treated with Tacrolimus

Background: The increasing use of tacrolimus as a primary immunosuppressant is paralleled by a growing number of pregnancies occurring in mothers receiving tacrolimus systemically.

Methods: In this retrospective analysis during 1992-1998; data sources were case reports from clinical studies, spontaneous reports from health care professionals, routine surveys by transplant registries, and the published literature.

Results: One hundred pregnancies in 84 mothers were recorded. Mean maternal age was 28 years. All except one mother (autoimmune disease) were solid organ transplant recipients (66% liver and 27% kid- ci ney). Mean time from transplantation to conception was 26 months. The mean daily dose of tacrolimus (range 11.7-12.8 mg/day) and the mean tacrolimus whole blood level (range 8.5-11.5 ng/ml) remained fairly constant from preconception through the third trimester. The most frequent maternal complications were graft rejection followed by preeclampsia, renal impairment, and infection. All cases of rejection were successfully treated with corticosteroids and did not result in graft loss. Of 100 pregnancies, 71 progressed to delivery (68 live births, 2 neonatal deaths, and 1 stillbirth), 24 were terminated (12 spontaneous and 12 induced), 2 pregnancies were ongoing, and 3 were lost to follow-up. Mean gestation period was 35 weeks with 59% deliveries being premature (<37 weeks). The birth weight (mean 2573 g) was appropriate for gestational age in 90% of cases. Most common complications in the neonate were hypoxia, hyperkalemia, and renal dysfunction. These were transient in nature. Four neonates presented with malformations, without any consistent pattern of affected organs.

Conclusion: Pregnancy in tacrolimus-treated transplant recipients resulted in a favourable outcome. Complications of the mother and neonate were similar to those previously described with other immunosuppressants.