Neck Loop

The cervical loop (ansa cervicales, Latin - ring collector, artery in the neck) is one of two arteries of the cervix, which join together at the base of the broad ligament of the uterus just above the border of the bladder and form a small canal called the “cervical loop”.

In nulliparous women, the length of the cervix is ​​usually about 4 centimeters. Its relative weakness is due to the negative pressure created by intrauterine pressure during gestation. The shorter the cervix, the less sensitive it is to stretching. Therefore, nulliparous women most often experience post-term pregnancy and entanglement of the umbilical cord. Moreover, they have an increased likelihood of cervical ruptures during childbirth due to weakness of the birth canal. Thus, in the United States, more than a third of women experience cervical rupture during their first birth.

The length of the cervix reaches 3 cm in a nulliparous woman of childbearing age in the middle of pregnancy, and by the end of pregnancy it increases to 2.5 cm. The flat parts of the anterior or posterior clivus are more vulnerable to injuries to the fetal head. When such parts are damaged and swollen with blood, the cervix becomes less sensitive to pressure.