S U/C I think you are the closest. To the best of my recolection it's not actually pressure changes but time spent at different pressures.
I remember seeing a doco on the ABC some years ago about the majority of airline pilot offspring being female due to the extented periods spent at high altitude. This was described as being results of an actual study on the bodies reaction to prolonged effects of low pressure. This was also raised during Human Performance and biology issues at uni. Although divers were never mentioned I guess it would make sence that high pressure would produce the opposite effect and they would have boys.
Conclusion: the only thing more expensive and time consuming than flying training and a career in aviation is children .... so choose your poison.