kara ʕ•́ᴥ•̀ʔ

This study found that mothers carrying boys showed a significantly larger increase in breast volume as early as the first trimester compared to those carrying girls. What’s wild is that the researchers found the difference was so distinct, breast volume increase was actually a more reliable predictor of the fetus's sex than many traditional physical "signs" combined. By the 32nd week, the volume difference between mothers of boys and girls in the study was a massive 141.32 ml. Since male fetuses require more energy and accumulate mass quicker, the maternal body physically scales up to keep up.