Pain tolerance

Maybe this should be in the off-topic forum but I want to know if it is related to training.

I have noticed that my pain threshold has become greater since I changed my diet and started seriously training. I am not talking about self-inflicted pain while lifting to failure, rather shit that would have hurt before doesn’t phase me anymore. Could higher GH or Testosterone lead to this? Or could it be something else? I always heard that women had greater pain tolerance for having to deal with childbirth. Any truth to this or insight on the topic?