Taking Tacrolimus during pregnancy or breast feeding A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Tacrolimus has been shown to cause harm to the fetus. If you think you may be pregnant, contact your doctor. You will need to discuss the benefits and risks of using Tacrolimus while you are pregnant. Tacrolimus is found in breast milk. Do not breast-feed while taking Tacrolimus .Tacrolimus is known to cross the placenta. In one case report, tacrolimus maternal and placental vein plasma concentrations were 0.49 ng/mL and 0.24 ng/mL, respectively, at delivery at 36 weeks gestation. The neonatal tacrolimus plasma concentration was 0.09 ng/mL three days after delivery and was undetectable at one week. The infant was normal at twelve months of age. In a study of 100 pregnancies in 84 mothers, 71 progressed to delivery, (68 live births, 2 neonatal deaths, and 1 stillborn), 24 were terminated (12 spontaneous and 12 induced), 2 pregnancies were ongoing, and 3 were lost to follow-up. The most common complications in the neonates were hypoxia, hyperkalemia, and renal dysfunction. All were transient in nature. Four neonates presented with malformations, without any consistent pattern of affected organs. In a series of nine pregnancies in nine liver transplant patients, tacrolimus was used as the primary immunosuppressive agent throughout gestation. Tacrolimus doses ranged from 4 to 64 mg per day. Corticosteroids were used concomitantly in four cases. Hyperkalemia was present in five of seven neonates for whom potassium levels were available. Potassium levels normalized over 24 to 48 hours after delivery without treatment. One neonate with high tacrolimus cord levels was anuric for 36 hours after delivery. Renal function was normal by one week of age. One infant, delivered at 22 weeks gestation, died two hours after birth. This pregnancy, conceived one month after transplantation, was complicated by cytomegalovirus infection.