The anatomical basis for a possible counter current exchange mechanism in the human adnexa.

A counter current mechanism for exchange of prostaglandins between veins and arteries in the ovarian pedicle has earlier been demonstrated in the sheep. The existance of a corresponding vascular arrangement in the human ovarian pedicle has been doubted predominantly on basis of functional data which do not support a role of prostaglandins for human luteolysis. However, the present study demonstrates norphological evidence for a similar vascular anatomy in the human as in the sheep. In 43 human adnexa studied, tortuous arteries in close contact with veins were consistently found. Microscopical sections revealed thinning of the vein walls at contact areas. The possible functional significance of this finding is discussed.