Men don’t need to stop IBD meds before conceiving a baby

By Robert Saunders

NEW YORK (Reuters Health) – When couples want to conceive, it’s unnecessary for men with inflammatory bowel disease to stop taking thiopurine medications, a Spanish group has shown.

This practice has been routine due to concerns that by interfering with purine metabolism, thiopurines can cause DNA mutations.

“The general perception is that thiopurines can be safely administered to female patients during pregnancy,” Dr. Carlos Teruel at Hospital Ramon y Cajal, Madrid, and colleagues wrote August 10th in an online issue of the American Journal of Gastroenterology. “However, information about thiopurine safety in pregnancies fathered by exposed males is both scarce and contradictory.”

A 2000 paper raised concerns about this question, Dr. Teruel told Reuters Health by e-mail. “In that piece of research, an increase in malformations and abortions was detected in the offspring from 13 male patients exposed to thiopurines,” he said.

To see if male IBD patients taking thiopurines have reduced fertility or if their offspring are adversely affected, the researchers looked at outcomes of 130 pregnancies. In all cases, the fathers had IBD; in 46 pregnancies, the fathers had been taking 6-mercaptopurine or azathioprine.

Time to conception was slightly but not significantly longer in the thiopurine-exposed group than the control group, and the number of unsuccessful pregnancies was similar at 10.9% and 13.1%, respectively.

“The difference in the proportion of premature births was not statistically significant (4.3% in the exposed group vs. 2.4% in the control group; OR: 1.3), and neither was the difference in the mean duration of the successful pregnancies (38.9 vs. 39.4 weeks),” the investigators report.

There was one congenital malformation in the exposed group and two in the control group, and no cases of congenital or infant neoplasia were seen during a median interval of 108 months after birth.

“Our results are not 100% conclusive. Medical research seldom is,” Dr. Teruel said. “Studying even larger samples, different results could be detected. However, due to the frequent appearance of adverse pregnancy outcomes (malformations, spontaneous abortions…) in the general population, the sample size needed would be unachievable. We have to live with this limitation.”

The team concludes there is no solid reason to recommend that male patients interrupt thiopurine therapy when trying to conceive. “These patients are treated for a good reason, and therapy interruption could have very negative effects in the course of their disease,” Dr. Teruel said. “Therefore, as has been our practice until now, we continue recommending our male (and female) patients who wish to conceive while on thiopurines, to continue their treatment.”

Nonetheless, the authors add, “When facing a patient in such a circumstance, it is essential to provide all the available evidence, empowering them to make a decision.”

SOURCE: http://link.reuters.com