And once inside the bitch, what does fresh semen live on? Have there really been studies of all of this or is it all speculation, because I've gotten quite the range of opinions. Normally, +2 and +4 days from ovulation (using 5ng as that base) is ideally what I've tried to target, but lately I've heard more folks using terms of "x days from LH surge" (and then the definition of the LH surge varies since most are not measuring that, but using the corresponding range in progesterone values). Some will call 4ng ovulation (ICSB as I recall), so perhaps the slightly earlier insemination is doing more than we think. Unfortunately, I have not been able to find concrete info on whether to expect the semen to live longer in the bitch vs in the fridge, and since this was only a 2 day extender, I punted and got the goods into her later today once Fedex finally arrived at 1pm. I couldn't bear the thought of looking at it on Thurs am, dead in the vial! Sure wasn't going to do anything that way, and yes, it was a 2 day extender unfortunately, so theoretically, it'd start to run out tomorrow. Oh well, have another coming for the end of the week and I'll confirm progesterone Thurs and can window that from there.