Final answer:
In an emergency delivery where medical supplies are limited, a clean piece of the mother's clothing may be used to tie off the umbilical cord if neither umbilical tape nor sterile gauze are available.
Step-by-step explanation:
When an emergency delivery occurs and medical supplies are limited, it is important to tie off the umbilical cord to prevent bleeding from the remaining stub after the cord is cut. The ideal material for tying off the umbilical cord would be a sterile material specifically designed for this purpose such as umbilical tape.
However, in an emergency situation without access to medical supplies, it may be necessary to use a clean piece of the mother's clothing, as it is likely to be more sanitary than other available materials. It is not recommended to use a paper towel for this purpose as it is not sterile and can easily break apart or introduce contaminants.
The umbilical cord typically contains two arteries and a vein, which are clamped and cut soon after birth, leaving a short section attached to the newborn which eventually dries and forms the navel. If available, sterile gauze can also be used to tie off the umbilical cord, but it is not as secure as umbilical tape. The purpose of tying off the umbilical cord is to prevent bleeding and infection until the residual umbilical stump dries and falls off, which usually occurs within three weeks of birth.