What is "foramen ovale"

n. (context medicine anatomy English) An opening in the septum between the right and left atria of the fetal heart that normally closes after birth.

At the base of the skull the foramen ovale (Latin: oval window) is one of the larger of the several holes (the foramina) that transmit nerves through the skull. The foramen ovale is situated in the posterior part of the sphenoid bone, posterolateral to the foramen rotundum.

In the fetal heart, the foramen ovale , also foramen Botalli, ostium secundum of Born or falx septi, allows blood to enter the left atrium from the right atrium. It is one of two fetal cardiac shunts, the other being the ductus arteriosus (which allows blood that still escapes to the right ventricle to bypass the pulmonary circulation). Another similar adaptation in the fetus is the ductus venosus. In most individuals, the foramen ovale closes at birth. It later forms the fossa ovalis.

There are multiple structures in the human body with the name foramen ovale (plural: foramina ovalia; Latin for "oval hole"):

• Foramen ovale (heart), in the fetal heart, a shunt from the right atrium to left atrium
• Foramen ovale (skull), at the base of the skull, one of the holes that transmit nerves through the skull
• Patent foramen ovale, a small channel in the heart, a remnant of the fetal foramen ovale