The Antidiabetic Drug Metformin and Male Fertility: An Update

Diabetes mellitus is a chronic disease with pandemic proportions. It has been estimated that 451 million people were diabetic in 2017 and recent statistics suggest that a worrisome 693 million people will suffer from diabetes in 2045 [1]. This metabolic disease is defined by impaired plasma glucose levels [2], which is due to insufficient insulin secretion or/and insulin resistance [3]. Thus, diminished insulin bioactivity causes a dysregulation on glucose metabolism in multiple tissues and, if not properly treated, hyperglycaemia and low insulin levels can evolve to other conditions and co-morbidities of distinct nature [4].