Diabetes warning: Common drug may increases risk of fathering boys with birth defects 

However, a study, currently being reviewed by the Medicines and Healthcare products Regulatory Agency, has suggested that some diabetic medications — specifically metformin, the first-line defence against type 2 diabetes — may also influence semen development and testosterone levels.

In their new study, public health researcher Professor Maarten Wensink of the University of Southern Denmark and his colleagues studied the outcomes from 1,116,779 births in Denmark between 1997 and 2006.

The team used national health databases to evaluate incidences of birth defects among the children and compare such to the use of three common diabetes drugs — insulin, metformin and sulfonylureas — by their fathers.

Injected insulin serves as a replacement for or supplement to the body’s natural supply. Metformin, meanwhile, lowers glucose production in the liver and makes the body more sensitive to insulin, whereas sulfonylureas stimulate the pancreas to make more insulin.

The researchers considered the children to have been exposed to these drugs if their father filled at least one insulin, metformin or sulfonylureas prescription during the three-month period prior to conception in which the fertilising sperm were developing.

Article source: https://www.express.co.uk/news/science/1587560/diabetes-warning-common-drug-metformin-risk-fathering-boys-birth-defects