Maternal and fetal outcomes in kidney donors are similar to non-donors

When a woman contemplates donating a kidney, she need not worry about any potential health risks it might pose to a future pregnancy, according to a paper being presented at the American Society of Nephrology's 41st Annual Meeting and Scientific Exposition in Philadelphia, Pennsylvania.

The research revealed that a woman who has donated a kidney does not face any additional risks of developing conditions such as hypertension or diabetes during a future pregnancy compared with women in the general population. In addition, female kidney donors do not face any increased risk of miscarriage or of giving birth prematurely.

While it is thought that women kidney donors can go on to have healthy pregnancies, the issue has not been well studied. To investigate, Sanjeev Akkina, MD, and his colleagues at the University of Minnesota, in Minneapolis, assessed fetal and maternal health in pregnancies occurring before and after kidney donation. They studied a total of 2025 women, the largest study to date, who donated kidneys since 1963. Over 1500 of them were successfully contacted; 965 reported becoming pregnant—822 donors reported 2416 pregnancies before donation and 223 reported 459 pregnancies after donation.

Pre-donation pregnancies were associated with an 83.7% likelihood of full-term deliveries compared with 72.3% in post-donation pregnancies. In addition, pre-donation pregnancies had a lower likelihood of miscarriage or fetal loss (11%) than post-donation pregnancies (19.8%). Pre-donation pregnancies vs post-donation pregnancies were also associated with a lower risk of gestational diabetes (0.7% vs 2.4%), gestational hypertension (0.4% vs 4.4%), and preeclampsia or pregnancy-induced high blood pressure (0.7% vs 5.2%). While post-donation pregnancies had a higher incidence of these various health conditions than pre-donation pregnancies, their incidence was comparable to those seen in the general population.

The increased risk in post donation pregnancies compared to pre-donation ones is probably due to the fact that these women were heavily screened for these conditions prior to donation and it is possible that those who had gestational diabetes, hypertension or preeclampsia never came forward to donate. "We believe this research is important so that future kidney donors are aware of the long-term effects [of the procedure]," said Dr. Akkina. "This study provides valuable information to female kidney donors of child-bearing age," he added.