Pregnancy outcome post renal transplantation.

Background: The success in performing organ transplantations and prevention of rejection has resulted not only in a substantial increase in life expectancy, but also improvement in the patients' quality of life. Thus, women who underwent organ transplantation are now reaching puberty and the age of reproduction. This has presented new challenges regarding the teratogenicity and the long-term effect of immunosuppressive medications used by these patients. Previous studies have shown that pregnancies after renal transplantation are associated with an increased risk for both the mother and the fetus. There is, however, very little information available on neonatal and long-term pediatric follow-up of babies born to mothers who have undergone renal transplantation and have been exposed to immunosuppressive medications, compared to controls. We report the experience of our center, the largest in Canada, regarding the prenatal and long-term postnatal outcome of pregnancies after renal transplantation.

Methods: This is a retrospective case series reporting the outcome of 44 consecutive pregnancies followed by the Toronto Renal Transplant Program. Follow-up data were gathered on the 32 live born children by either a return visit to the clinic or by telephone interview. Medical, as well as developmental information, was gathered on all children and the study group was compared to controls, matched for maternal age (+/-2 years) and smoking status, obtained through the Motherisk Program.

Results: Of the 44 pregnancies followed by us, there were 32 live-born children delivered by 26 mothers and 12 stillborn/abortuses. Twenty-six pregnancies were treated with cyclosporine, azathioprine and prednisone, 13 with azathioprine and prednisone and five with cyclosporine and prednisone. The mean gestational age at delivery in the study group was 36.5 +/- 2.7 weeks compared to 40.2 +/- 1.6 weeks in the control group (P < 0.001). The mean birthweight in the study group was 2.54 +/- 0.67 kg, compared to 3.59 +/- 0.53 kg in the control group (P < 0.0001). In the study group there was one child with multiple anomalies and four stillbirths compared to zero in the control group. There were also six spontaneous abortions and two therapeutic abortions in the study group. On follow-up (from 3 months to 11 years of age) there was one child with insulin-dependent diabetes mellitus, two children with asthma and one child with recurrent otitis media. Developmental follow-up revealed one child with moderate to severe sensorineural hearing loss, one child with a learning disability and one child with pervasive developmental disorder. In none of these cases were there signs of perinatal asphyxia.

Conclusion: There are significantly more stillbirths, preterm deliveries and increased incidence of low birth weight in the transplant group. Most pregnancies in the study group went well, however, and their offspring had normal postnatal growth and development. Further studies with long-term pediatric follow-up are needed to delineate their outcome and rule out possible long term effects of the immunosuppressive medication on their growth, development, reproduction and general health.