In a groundbreaking discovery that could affect millions of potential fathers, researchers at the University of Sheffield have uncovered concerning evidence about marijuana’s impact on male fertility.

UK: For couples struggling with infertility, there are few lifestyle changes men can make to improve the size and shape of their sperm, suggests a new study. Sperm shape and size - known as morphology ...

(CNN) — Marijuana may damage oocytes — unfertilized eggs in female ovaries — in ways researchers worry may lead to infertility, miscarriage and possible genetic defects in babies, new research has ...

ST. PETERSBURG, Fla. — Men who smoked marijuana could have an increased sperm count than those who lay off the reefer, though don't light up just yet. The result shocked researchers who measured the ...

High levels of THC -- the compound in marijuana that causes a "high" -- may affect how eggs develop and could lead to fertility problems, miscarriages and chromosome issues in embryos, new research ...