(KRON/CNN) — There is news in the search for a male version of a birth control pill.

It Is something doctors have tried and failed to find for years.

A new international study shows a birth control injection seems to work, but the problem is men can’t handle the emotions that accompany it, according to CNN.

The side effects include mood swings, depression, acne, and increased libido. The emotional problems got so bad in some cases, the study was cut short.

On the other hand, of the roughly 300 men who got the shots, only four became fathers.

The injection involved a cocktail of hormones. It all sounds promising, but the gender gap in contraceptive use probably won’t close anytime soon.

No further development is planned for the shot, with the study’s authors saying a lot more research is needed.