Longer, More Frequent Dialyzation in Pregnant Women Leads to Healthier Babies

February 17, 2014

Pregnant women who require dialysis have healthier babies and fewer pregnancy complications when they receive dialysis for more than 36 hours per week, researchers report.

More frequent and longer dialysis sessions for pregnant women increased the live birth rate, reduced pregnancy complications, and resulted in infants with healthier birth weights, researchers reported in the Journal of the American Society of Nephrology. 

Pertinent Points:

- In pregnant women with established kidney failure at conception, the live birth rate was better with a more intensive dialysis treatment protocol. For women dialyzed for more than 36 hours per week, the live birth rate was 85%, while it was 48% in women dialyzed for 20 hours or less per week.

- Infants had a healthier birth weight and fewer, more manageable complications when women were dialyzed for more than 20 hours per week.

Pregnant women, and those who wish to become pregnant, who are on dialysis care should consider more frequent and longer dialysis sessions, the authors suggest. 

"More intensive dialysis has improved pregnancy rates and dramatically improved pregnancy outcomes," said Michelle Hladunewich, MD, of Sunnybrook Health Sciences Centre, in Toronto. "This study provides hope to young women on dialysis who might want to consider having a family."

To assess the effects of intensive dialysis on pregnancy outcomes, the researchers compared young female dialysis patients from Toronto, Canada, with those from the United States. In Canada, more frequent dialysis averaging 43 hours a week is used in young women. In comparison, dialysis treatments averaging 17 hours a week are the standard for young women in the United States.

The analysis revealed that pregnant women with kidney failure who underwent dialysis for more than 36 hours per week had a live birth rate of 85%. By comparison, those who underwent dialysis for 20 hours a week or less had a live birth rate of 48%.

In addition, the Canadian women who underwent more intense dialysis had a median duration of pregnancy of 36 weeks compared with 27 weeks in American women, the researchers found.

Using the Toronto Pregnancy and Kidney Disease Clinic and Registry (2000-2013), researchers identified 22 pregnancies to include in the analysis. For US participants, the researchers relied on the American Registry for Pregnancy in Dialysis Patients (1990-2011) to identify 70 pregnancies.

References:

Hladunewich MA, Hou S, Odutayo A, et al. Intensive hemodialysis associates with improved pregnancy outcomes: a Canadian and United States cohort comparison. J Am Soc Nephrol. February 13, 2014. doi: 10.1681/ASN.2013080825.