And correlated with decreased sperm quality and count. Considering the sheer amount of bad health outcomes that are also associated with obesity in general, it's not surprising that it also affects fertility.
Question then becomes, if you adjust for obesity, how much has male fertility changed since 80 years ago?
We have lab data showing that microplastics also disrupt metabolisms. So this is not quite the escape hatch we might wish it was: we have good reason to suspect that microplastics are also contributing to obesity.
(Of course this doesn't fully remove our extremely sedentary lifestyle and highly unnatural food supply either)
Question then becomes, if you adjust for obesity, how much has male fertility changed since 80 years ago?