Do you gain more with a boy or girl?

When mothers gained 20 lb, roughly 49% of babies born were boys. But when mothers gained 40 lb, the likelihood of having a boy increased, with about 52.5% of babies born being males. And at 60 lb gained, about 54% of babies were boys.

I hypothesized that the ratio of male to female babies born should vary with the amount of weight gained during gestation." “I predicted that women who gain low amounts of weight during gestation should produce significantly more females, and that, if gestational weight gain directly influences sex ratios, fetal losses would be more likely to be male when women gain inadequate amounts of weight during pregnancy.”