Premature Ligation of the Umbilical Cord
by Patricia Edmonds
© 2013 Midwifery Today, Inc. All rights reserved.
[Editor’s note: This is an excerpt of an article which appears in Midwifery Today, Issue 108, Winter 2013. View other great articles and columns in the table of contents. To read the rest of this article, order your copy of Midwifery Today, Issue 108.]
The umbilical cord is a distinctive anatomical structure by about 22 days post conception. It is recognizable as the connecting stalk between the chorion and the primitive cardiovascular system.
My favorite description of the development of the umbilical cord comes from an old text, Science and Art of Midwifery (Lusk 1884). (The copy I have was originally purchased the year of publication by F.D. Prentice, MD, and beautifully claimed by the owner with an elegant flourished signature. He also left a smattering of handwritten notes throughout the text as well as an account of the development of the Chamberlain Forceps, handwritten no doubt with a quill!) Lusk writes:
To understand the structure of the cord, it is well to bear in mind the various particulars connected with its development. At the time when the allantois first appears as a sac-like projection from the intestine, the embryo is hardly more than an appendage to the umbilical vesicle. The larger size of the latter directs the allantois over the posterior extremity of the fetus. By its growth and extension, the allantois reaches the chorion, and forms a sort of pedicle, by means of which a vascular communication is established between the embryo, and the periphery of the ovum. This pedicle is the first indication of the umbilical cord. The fully developed cord consists, therefore, of a sheath from the amnion, the gelatine of Wharton, the umbilical vein and arteries, and traces of the umbilical vesicle, and the pedicle of the allantois. (Lusk 1884, 57–58)
The allantois (a sac-like projection from the intestine) does not function in the human embryo but blood formation occurs within its walls during the third to fifth weeks of gestation and its blood vessels become the umbilical vein and arteries. The intraembryonic portion of the allantois runs from the umbilicus to the urinary bladder. As the bladder enlarges, the allantois involutes to form a tube called the urachas. After birth the urachas becomes a fibrous cord called the median umbilical ligament. If this remains patent (patent urachas), leakage from the urinary bladder through the umbilicus may persist into adulthood.
To Cut or Not to Cut
The placenta and cord are, in effect, organs of the newborn. The cord develops from the same tissue that makes up the fetal side of the placenta and this tissue is contiguous with the baby’s skin. Cord clamping is the first medical intervention experienced by most humans as part of the third stage of labor. Delay in clamping and cutting of the umbilical cord improves neonatal cardiopulmonary adaptation, increases blood pressure, improves oxygen transport and red blood cell flow, reduces the number of days on ventilation and oxygen with sick and premature infants and reduces the incidence of anemia.
- Lusk, William Thompson. 1884. The Art and Science of Midwifery. D Appleton and Company: New York.
- Lemay, G. “Five Good Reasons to Delay Clamping the Cord.” Gentlebirth.org. Accessed October 31, 2013. http://www.gentlebirth.org/archives/lateClamping.html.
- Moore, Keith L. 1977. The Developing Human, Clinically Oriented Embryology, Second Edition. WB Saunders Company: Philadelphia.
- Morley, G. 2002. “How the Cord Clamp Injures Your Baby’s Brain.” Mercola.com. Accessed October 31, 2013. http://articles.mercola.com/sites/articles/archive/2002/03/20/clamp.aspx.
- Schuler-Maloney, Doris, Steve Lee and Marty Boesenberg. 1998. The Placenta: To Know Me Is To Love Me. St. Mary’s, Iowa: DSM Pathworks.
Patricia Edmonds has been serving as a midwife for the past 37 years. She began her path to birth as a child at the feet of her grandmother, who served her family and community as a traditional healer. Finding nursing school to be the wrong direction for her desire to follow in her grandmother’s footsteps, Patricia withdrew and enrolled in the Northwestern School for Practical Midwifery. For the past few years, Patricia has served on the faculty of several midwifery schools and conferences, including the Trust Birth conferences.
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