If you thought a birth control shot for men was impossible, think again.

A new study, published in The Journal of Clinical Endocrinology, tested the efficacy of a male birth control injection in 320 healthy men in monogamous relationships.

Though the shot was 96 percent effective at preventing pregnancies, the study was terminated early due to negative side effects.

The male birth control injection

The men involved in the study were given a series of testosterone and “progestin” shots to lower their sperm count. Testosterone supplementation shuts down testicular function and reduces fertility.

And though the injection achieved the desired result of preventing pregnancies, it also caused adverse effects. Many participants experienced muscle pain, acne, depression and moodiness.  And a few participants had problems regaining their fertility.

“After reviewing the study, I'm very surprised it was actually even approved in any manner,” says Matthew Sand, M.D., a urologist at Piedmont. “Giving patients testosterone when they don’t need it can make you infertile, and it might be permanent. It can also lead to endocrine, or hormonal side effects that are concerning.”

Dr. Sand says testosterone can cause anger issues and short-temperedness.

“You'll have highs and lows, almost like a bipolar disorder,” Dr. Sand says.  “At one point you feel very energetic.  And then you have a low period as you're coming down, which leaves you relatively depressed as a side effect.”  

Testosterone injections can also cause serious medical conditions, like increasing your blood cell count, liver dysfunction and prostate growth.  

“These are not things that you would want to deal with as a side effect of birth control, especially when there are much less risky alternatives,” Dr. Sand says.

The male birth control injection won’t be on the market any time soon. For men looking for a permanent and effective form of birth control, Dr. Sand recommends a vasectomy.

“A vasectomy is a good permanent option without significant risk,” Dr. Sand says.  “And it’s easy to recover from.”

To find a urologist near you, click here.