Updated: Jul 29
The umbilical cord- the physical connection between the mother and growing baby, the lifeline conduit between placenta and foetus. Let's delve a bit deeper with 10 facts:
What's in a word?
It is derived from: Latin umbilicus "the navel" also "the centre of anything"  Defined as:
relating to or affecting the navel or umbilical cord
extremely close; inseparable "the umbilical link between commerce and international rugby"
(of a pipe or cable) connecting someone or something to a source of essential supplies " a tractor-mounted unit in the field is fed through an umbilical hose"
Innie or outie?
Contrary to popular belief, the shape of your tummy button is NOT as a result of the way your umbilical cord was cut and clamped but a matter of chance or because of a medical condition (like a diagnosed or undiagnosed hernia). Did you know that 90% of people have an 'innie?'
The hole truth
The umbilical cord contains one vein, which carries oxygenated, nutrient-rich blood to the foetus and two arteries that carry deoxygenated, nutrient-depleted blood away from baby via the placenta.  Occasionally, a cord may only have two vessels.
The eggciting way that the cord forms
After conception, the fertilised egg turns into two components: one is the embryo that will develop into your baby, and the other is the placenta. The umbilical cord develops out of the embryonic tissue and continues to grow until your baby is born.
While lengths can vary GREATLY, an average umbilical cord is 55 cm long, with a diameter of 1-2 cm and 11 helices (spirals). 
Lumps, bumps, knots and jelly.
Bumps along the umbilical cord are common and are known as false knots , caused by extra looping of the blood vessels inside the Wharton's jelly. These pose no risk. 1-2% of cords will have a true knot whereby the umbilical cord loops or weaves around itself, causing a knot. In most cases these are not dangerous since the cord contains a gelatinous substance called Wharton's jelly which keeps the cord flexible and protects the blood vessels inside.  Similarly, a nuchal cord, where the cord wraps around a baby's neck (sometimes more than once!) does not usually pose a problem.
Delayed/optimal cord clamping
More people than ever are now opting for delayed or optimal cord clamping, rather than immediate clamping and this is now recommended (and should be standard practice) for most babies. Delayed cord clamping is classed as 1-3 minutes after birth though some parents opt to wait until the cord stops pulsing (optimal cord clamping) to ensure that baby receives as much blood as possible from the placenta. It is estimated that immediate clamping leaves 1/3 of babies' blood in the placenta. The benefits of delayed or optimal cord clamping include increased iron levels for baby (iron being essential for brain development) and more stable blood pressure immediately after birth  as well as the stem cells and immune cells and decreased risk of anaemia. Some parents practice what is known as a lotus birth- where the cord is not clamped at all but left intact until it releases of its own accord.
Stem cell studies
Stem cells are special human cells that are able to develop into many different cell types and some can fix damaged tissue. Researchers believe that stem cells may soon be used to treat illnesses such as Alzheimers, paralysis, type 1 diabetes, spinal cord injuries, rheumatoid arthritis, asthma and many more.  Where can these healing stem cells be found? You guessed it- in the umbilical cord and placenta.
To bank or not to bank?
Some parents choose to have cord blood rich in stem cells diverted from the baby's umbilical cord through early cord clamping and cutting, to freeze for long-term storage at a cord blood bank should the child ever require the cord blood stem cells (for example, to replace bone marrow destroyed when treating leukemia). This practice is controversial, with critics asserting that early cord blood withdrawal at the time of birth actually increases the likelihood of childhood disease, due to the high volume of blood taken (an average of 108ml) in relation to the baby's total supply (typically 300ml).  The Royal College of Obstetricians and Gynaecologists stated in 2006 that "there is still insufficient evidence to recommend directed commercial cord blood collection and stem-cell storage in low-risk families". 
No sense no feeling!
There are no nerves in the umbilical cord so neither baby nor mum feel the cutting on a physical level.
So there you have it- 10 pieces of information about the umbilical cord. Crucial to our existence in utero, we may find it becoming more and more a part of our lives in the future too due to its stem cells. Did anything surprise you? Do you have any questions? Let me know in the comments.
1 etymonline.com 2 ncbi.nlm.nih.gov Placenta Blood Circulation - Vascular Biology of the Placenta
5 UHS NHS Delayed Cord Clamping Patient Leaflet
7 McDonald, S. J.; Middleton, P.; Dowswell, T.; Morris, P. S. (2013). McDonald, Susan J (ed.). "Effect of timing of umbilical cord clamping of term infants on maternal and neonatal outcomes". The Cochrane Database of Systematic Reviews. 7 (7): CD004074. doi:10.1002/14651858.CD004074.pub3. PMC 6544813. 8 RCOG/RCM statement on umbilical cord blood collection and banking