My Ob told me approx half an hour after the birth of DS2 that if we decided to have a third we had a greater than 60pc chance of having another boy! Well, here we are with a third boy on the way Not sure what the reasoning is but presume it may have something to do with my body being more accepting of boy sperm?? Having said that, we didn't try to gender sway with the timing of sex or anything else.