I think it has a lot to do with the freezing procedure as the female sperm tends to succumb in poor conditions. The number I heard when we were TTC was closer to 60% likelihood of frozen sperm producing male babies. Our bank claimed their samples resulted in a 55% male /45% female split. That said, our donor's frozen sperm has resulted in 10 boys (2 of which are mine) and 2 girls last I checked.
12/28/11 at 4:43pm