>>3155974No it isn't - it's "supposed" to happen in human reproduction.
Theory goes that sex while pregnant is an advantage to the developing foetus because sex passes immune system antibodies between man & woman, and the foetus gets the benefit of a boosted immune system.
It also stops the woman's body from treating the foetus as a foreign entity & rejecting it. The same holds true for getting her pregnant in the first place - if she's "acclimatised" to the guys cum, she's more likely to get preggers & less likely to have a miscarriage.
But the most effective way of conditioning your immune system to adapt to your partners is to get those antibodies into the area of the body with the most lymphatic system glands - the throat.
That's right - oral makes the woman more likely to later conceive