Too bad this is such a poorly written/quack study... dude's a psychologist... what does he know any of this? Either he's full of it, or the person who wrote it is...
Gallup believes the reason a pregnant woman gets morning sickness is due to the unfamiliar semen in their body due to the pregnancy.
More like she's pregnant due to sperm...
Gallup says in his findings that the woman’s body will initially reject the father’s semen as an infection and react to it by vomiting.
He HAS no findings, because this wasn't a study.. just a quack's pet argument. That is also his reasoning why all his dates threw up on him during sex... obviously their body was rejecting his semen.
Basically what he has here is an argument he's fabricated based on actual studies (of what he only read the ABSTRACT of one), but his has been pushed back a few hundred years. Sounds like he's saying that the man's "essence/energy/chi/etc" is within her and growing, and that she more exposure to that essence will make things better... I'm sure that men in the middle ages use the same logic... if your woman is trusting, gullible or dumb (or just likes sucking you off), good for you, feel free to try this argument.
There ARE studies that show that using non barrier methods of birth control (pill, etc) prior to conception will improve chances of getting and staying pregnant once you stop birth control. This is thought to be related to the female's immune system being exposed to the sperm over an extended period of time, resulting less strong of a response. If she has no exposure to the sperm, once you 'start trying', the sperm is perceived more as a foreign invader and may trigger responses that prevent fertilization/implantation.