I forgot the one clinical thing that was different. I will apologise for TMI straight up.

The first cycle we used DH sperm that he had ejeculated. We tranferred 1 and froze 5. When we thawed the 5 none survived the thaw.

The second cycle we used TESA/PESA as in a neddle to get the sperm. We transffered 2 that didn't work, although I did had mild OHS. We later did an FET and thawed 2 and they both survived thus we transferred two resulting in a BFP.