Male GS unable to Tie with female HELP - Page 2

    I would like to know "other " theories on this issus. Anyone have any other reasons???

is your female really standing and flagging.?
if she is not ready she may not be large enough yet.

I think it is most likely that she is not ready yet, but I agree with Uber land best to keep them separate and try again tomorrow. Good luck.

I had a heck of a time breeding my bitch who I recently spayed. Her vagina never did relax, so the male kept hitting a brick wall about an inch inside of her. When I did a digital exam, she clamped down on my finger and I was afraid I wouldn't be able to get it out without hurting her! It was NOT a stricture. It didn't matter at what point in her cycle we tried to breed her, nor what the blood tests said. She is just a big doggy bitch who only conceived once (by AI), when she was 3. Maybe you should get brave and go in to see if she's normal in there. 

I believe from the first post that she has already bred before with the same male and had a litter though.

Could be that she's thrown a false heat.... or that there's some kind of infection which you're mistaking for a heat.  Might be wise to have a vag culture done to be sure she's clear and what stage of heat she's in.   Also be sure to present them for breeding in a cool place to prevent overheating.