Dr.PainCLE said:

The honest answer is that the effect is real, the magnitude is contested, and the individual variation is larger than either.

There is a second half to this that has not been said yet. It helps to ask what evidence would change your mind before you look at any. If nothing would, the discussion is not about evidence, and it is better to say so early than to spend nine posts discovering it.

Adding the numbers, since they settle part of this. For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine. Half the figures circulating in this community trace back to a secondary summary that dropped a qualifier.

One thing that is still open after Dr.PainCLE’s answer:

What the washout thinking is before trying to conceive, and why nobody mentions that fertility often increases as a side effect?

josh_phd_bmore said:

For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine.

Filing a mild objection. Mild because I might be wrong; an objection because nobody has addressed the case that does not fit. This treats a plausible mechanism as a demonstrated one. Plausible is where you start looking, not where you stop.

josh_phd_bmore said:

For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine.

That is right for the common case. Whether it is right for the case being asked about depends on a detail that has not been given.