I'm puzzled when researchers don't take one more step, and design a great study. They knew that a F3 third generation was needed to at least demonstrate "the impact on F2 fertility." A F3 generation may have also provided evidence for or against transgenerational epigenetic inheritance, because those subjects' cells would have had no direct exposure effects from analgesics.
Epigenetics research that was designed to fall one step short of wonderful | Surface Your Real Self