Even in the womb, where all oxygen is provided by the parental placenta, fetuses can—and do—yawn. More yawns during observation were associated with a lower weight at birth—potentially indicating mild fetal stress in the womb, according to a study published in PLOS One by Damiano Menin, of the Università degli Studi di Ferrara in Italy, and colleagues.
This article was originally published on MedicalXpress.com

