Are pregnancies shorter in leap years?
Basso
O
O
Fonager
K
K
Olsen
J
J
D036861:Delivery, Obstetric / Q000706:statistics & numerical data*; D003718:Denmark; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D012042:Registries; D013997:Time Factors