Hello guys

Does anyone here have their dogs administered with IVOMEC injectibles monthly as a Heartworm preventive?
Ivermectin is the ingredient.

I heard that it can affect a bitch's fertility?

I was wondering if this is true as my dogs are given ivermectin every month for life as a preventive. And my GSD failed to conceive (we bred her three times to no avail) and then now, my beagle was bred once with no pregnancy.

Thanks.