Читать книгу The Female Physician - John Maubray - Страница 20

CHAP. XIII. Of the UMBILICAL VESSELS, or NAVEL-STRING.

Table of Contents

THE three Umbilical Vessels consist of one Vein and Two Arteries; which compose the NAVEL-STRING, and are wrap’d up in one strong Membrane, proceeding from the Chorion and Amnion, between the Navel and Placenta.

THE Vein arises in the Placenta, from innumerable minute Vessels; proceeding thence with Spiral Contortions between the Arteries, thro’ the NAVEL-STRING, and Navel, to the Liver of the Infant; terminating in the Sinus of the Vena Porta, into which it pours the Blood and nutritious Juice received in the Placenta; which immediately proceeds to the Vena Cava, and Heart, thro’ a Cylindrical Canal (call’d Venosus) opposite to the Umbilical Vein.

THE Arteries, which are scarce half so large as the Vein, arise from the Iliacs of the Infant, or from the Aorta. They pass both Sides of the Bladder to the Navel, and thence through the NAVEL-STRING, by the like Spiral Windings, to the Placenta: where, after distributing some Branches to the Amnion and Chorion; they are divided into a very great Number of Sprigs, transferring the Blood from the Fœtus to the SECUNDINE.

THESE Two Arteries, with the above-mentioned one Vein, make up a certain Part, twisted like a Rope, about one Inch thick, and near a Yard long, call’d the NAVEL-STRING; which is so ordained of this Length, that the Infant, by its Motion, may not pull the Placenta from the Womb; and that, by its Means, the SECUNDINE may be commodiously extracted after the Birth.

IN Case of Twins, or more Children, every one has its proper NAVEL-STRING; the chief Use of which is, to convey the Maternal Blood and nutritious Juices by the Veins to the Foetus, for its Aliment: The Arteries carrying back that which is unfit for this Use, to the Placenta; whilst the Fœtus is still supply’d with more by the Vein: So that there’s a continual Circulation, or Communication, between the Mother and her Infant.