I'm the eldest of 4 girls (no brothers), but my Dad is the eldest of 3 boys (no sisters). Strangely enough, his brother also has a daughter but no son, and my sister has a son but no daughter - I thinking it's probably a genetic quirk
Funny you say that because my Mum is the eldest of 4 girls and between the 4 sisters they have 10 kids, 5 boys and 5 girls and then grandchildren is 2 boys, 2 girls oops forgot my newborn nephew, 3 boys.

Interesting topic, I see how an allergic reaction to sperm may be very possible, but not so sure about that resulting in female children only, if anything a reaction to the chromosome rather than the sperm itself.