high-vax, low-effect countries like France need explanation, though. Even if it is multifactoral.

Was there a difference in which shots were used? Could it be a difference between vax batches? Any way to track what went where? Any correlation between genetic subgroups? How much immigration are we talking about in various countries? We do know where the most UKR refugees are showing up-- can we bust those countries out and analyze them separately? Is there any correlation by total population vs. rate of recent immigration?

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The vax-sperm-quality study found that after an initial sperm-quality decrease the median but not the average sperm quality recovered. This suggests that a subgroup of below 50percentile sperm-quality donors suffered a persistent quality decline. This would be consistent with a "sub-group-hypothesis": there is no comulative fertility effect of the vaccines, because the fertility decline is due to a persistent effect in a subgroup after initial vaccination.

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I was critical of this view earlier, so now that more data is in I agree it looks like there is something happening beyond the "not tonight darling" effect.

Is there data separated by first versus second and later births? It could be useful because we might reasonably expect different causes to affect first vs later births differently.

Vaccine reduces fertility across the board: Probably equal effect on first and later births, so no change from the pre-vax era to the post-vax era.

Vaccine reduces fertility in some men and women: Probably equal effect on first and later births.

Lockdown caused less pair bonding: Probably higher reduction in first births than second and later (complicated by people who have children but would have been looking for a new partner)

Concerns about economy/war/don't want to bring children into a world run by Klaus Schwab: Who knows if there would be a differential effect..

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