Does firstborn son disadvantage subsequent pregnancies/siblings?

[Goostacean]

Hi, as per title, DH apparently read somewhere that high levels of testosterone during pregnancy with a male child disadvantages the womb for second (and subsequent?) pregnancies/children. Not a reason not to have DC2, but possibly a reason for wider spacing.

Googling hasn't brought up anything - has anyone heard of this, or knows where I can find any more information?? Happy to be told it's completely fabricated :D

I've never heard of this. What does disadvantage mean? More likely to miscarry?

I think it was to do with e.g. low birth weight, increased chance of premature birth, and similar.