The cervical mucous plug is created by which glands?

The cervical mucous plug is primarily produced by the endocervical glands, which are located in the cervical canal. These glands secrete thick mucus that forms a protective barrier during pregnancy. The purpose of this mucous plug is to seal the cervix, helping to prevent bacteria and other pathogens from entering the uterus and protecting the developing fetus. The composition of this mucus changes throughout the menstrual cycle and more significantly during pregnancy, becoming thicker and more viscous to provide optimal protection.

Other glands, such as those in the ovaries, endometrium, and placenta, play vital roles in reproduction and hormone production but do not directly contribute to the formation of the cervical mucous plug. Therefore, the endocervical glands are the correct answer, as they specifically produce the mucus that forms this important protective barrier during pregnancy.