There's actually been quite a bit of research into seminal priming; here's a review article
that says For induction of major histocompatibility complex (MHC) class I-specific tolerance, long-term exposure to seminal fluid, which contains paternal soluble MHC class I antigens, may induce paternal MHC class I-specific tolerance.
That means that one particular thing that our immune systems could fail to tolerate in pregnancy seems to be related to prior exposure to the partner's proteins, where more exposure means better tolerance for the foreign placenta.
There's also some research showing that a shorter period of cohabitation
with the partner prior to conception is correlated to a higher risk of preeclampsia.
But if you don't control for other conditions like advanced maternal age, this could be misleading -- older women are more likely to attempt pregnancy early in a relationship than younger women *and* more likely to get preeclampsia -- so they have also looked at a relationship with barrier contraception
, and found that once you sort the populations by age, a link between seminal exposure and preeclampsia disappears. In unadjusted analyses, a prolonged time to conception was associated with preeclampsia (OR 1.9), however, after adjustment, the association was less prominent (OR 1.6) and after stratification by contraception method, the link between time to conception and preeclampsia was eliminated.
So that means maybe seminal priming affects tolerance of one particular class of the partner's antigens, but this doesn't really seem to have a whole lot to do with preeclampsia, or else we'd see higher rates of PE in people with less exposure, and this apparently doesn't happen.
I am fond of the work on the genetic mismatch betweenHLA-C and KIR
, because it provides a nice clean explanation for what goes wrong, with no role for MOAR SEXZ nor MOAR PROTEENS. (As a gal who'd been married for 9 years preconception and who'd been on the Brewer diet, I could rather safely rule both those suggestions out.)
Briefly, it says that it comes down to a genetic mismatch between the receptors in the maternal killer cells in the uterine lining, and the signals generated by the paternally-derived trophoblastic invasive cells that help form the placenta. The key just doesn't fit the lock, and so before you even know you're pregnant (during implantation), things go completely sideways.
But thinking about this is harder than saying, well, most people who do X don't get it, so therefore since you got it you didn't do X. It makes them safe. They won't get it because they Did Everything Right.
Also, infertiles, if you just relax you'll get pregnant! And it's the fault of diabetics because they're fat! And if your blood pressure is up you should try constructive self-talk!
This is pre-scientific "thinking", and thinking is in scare quotes for a reason.