BACKGROUND Young women wishing to become living kidney donors frequently ask whether nephrectomy will affect their future pregnancies. METHODS We conducted a retrospective cohort study of living kidney donors involving 85 women (131 pregnancies after cohort entry) who were matched in a 1:6 ratio with 510 healthy nondonors from the general population (788 pregnancies after cohort entry). Kidney donations occurred between 1992 and 2009 in Ontario, Canada, with follow-up through linked health care databases until March 2013. Donors and nondonors were matched with respect to age, year of cohort entry, residency (urban or rural), income, number of pregnancies before cohort entry, and the time to the first pregnancy after cohort entry. The primary outcome was a hospital diagnosis of gestational hypertension or preeclampsia. Secondary outcomes were each component of the primary outcome examined separately and other maternal and fetal outcomes. RESULTS Gestational hypertension or preeclampsia was more common among living kidney donors than among nondonors (occurring in 15 of 131 pregnancies [11%] vs. 38 of 788 pregnancies [5%]; odds ratio for donors, 2.4; 95% confidence interval, 1.2 to 5.0; P = 0.01). Each component of the primary outcome was also more common among donors (odds ratio, 2.5 for gestational hypertension and 2.4 for preeclampsia). There were no significant differences between donors and nondonors with respect to rates of preterm birth (8% and 7%, respectively) or low birth weight (6% and 4%, respectively). There were no reports of maternal death, stillbirth, or neonatal death among the donors. Most women had uncomplicated pregnancies after donation. CONCLUSIONS Gestational hypertension or preeclampsia was more likely to be diagnosed in kidney donors than in matched nondonors with similar indicators of baseline health. (Funded by the Canadian Institutes of Health Research and others.)

Comorbidity was prognostic in subsets of nasopharyngeal, oropharyngeal, oral cavity, and laryngeal cancers. Comorbidity may be a partial surrogate for age and social habits.

Currently, the majority of living kidney donors are women, and these young-women donors are often concerned about the possible effect of kidney donation on future pregnancies. Animal studies have shown evidence of higher blood pressure and urinary protein excretion in animals with 1 kidney compared with animals with 2. However, human studies that have compared donors with healthy nondonors during pregnancy have yielded conflicting results.In this retrospective, matched-cohort study, the authors compared kidney donors to matched, healthy nondonors with regard to risk of developing gestational hypertension or preeclampsia, as well as other maternal and fetal outcomes. They used databases in Ontario to compare pregnancy outcomes in 85 eligible women who donated a kidney between 1992 and 2010 with 510 healthy, nondonors. Baseline characteristics compared were age at the time of cohort entry, urban or rural location, income, the number of pregnancies at 20 weeks' gestation at cohort entry, and time to first pregnancy after cohort entry. The primary outcome was obtained from diagnostic codes for gestational hypertension or preeclampsia; secondary outcomes examined more specifically other maternal and fetal outcomes.Over an approximately 11-year period, 595 women were followed up through their pregnancies. Donors and nondonors had the same number of doctor visits during pregnancy, but gestational hypertension or preeclampsia was higher among donors (11% vs 5%; odds ratio for donors, 2.4; 95% confidence interval, 1.2-5.0; P = 0.01). Secondary outcomes revealed no significant difference in the rate of preterm birth (8% vs 7%) and low birth weight (6% vs 4%). There were no reports of miscarriage, stillbirth, or maternal death in either group.The risks of gestational hypertension or preeclampsia are higher in kidney donors than in nondonors with similar baseline health.