5.1 Significance of Histology of Cervix
Histological analysis of the Cervix is an important aspect from the point of this study as this study us related to the changes in the tissue and cellular level of that of the Cervix and thus is worth mentioning in the Thesis. Also histological study is worth in effective cytological screening, Colposcopy and biopsy results in the management of Cervical Neoplasia. The epithelium is variable in different areas of the Cervix.
5.2. Epithelium of the Ectocervix and Endocervix
Histological studies of the epithelium of the Ectocervix show that the cellular layers are composed of nonkeratinized stratified squamous epithelium. The epithelium of the Endocervix is composed of simple columnar epithelium.
5.3 Epithelium of the areas adjacent Ectocervix and Endocervix
The area around the Ectocervix and Endocervix is known as the transformation zone. This transformation zone undergoes metaplasia for a number of times during the normal and healthy span of life of a female. Thus when the epithelium of the transformation zone is exposed to the acidic medium of the Vagina, it undergoes metaplasia to squamous epithelium and when the epithelium of the transformation zone enters the less acidic environment of the Uterus, it undergoes metaplasia to columnar epithelium.
5.4. Times when metaplasia of transformation zone occurs
There are certain significant stages of life in a woman related to the metaplasia of the transformation when it should occur; other than the otherwise normal changes in the transformation zone.
The first significant metaplasia occurs at puberty when the Endocervix everts out of the Uterus.
The second significant metaplasia occurs with the changes occur in the cervix with every normal menstrual cycle.
The third significant change occurs with the post menopause phase when the Uterus shrinks thus moving the Transformation zone upwards.
5.5. The Cervical Mucus
The Mucus of the Cervix also undergoes variable changes and also changes its property from being fertile to infertile and vice versa.
When the menses of a woman stop after the menstrual period, the external Os of the cervix is blocked by mucus which is thick and prevents the sperm from entering into the Uterus. This infertile block gets changed by a fertile type of mucus which is sperm friendly and also helps in nourishing the Sperm and allowing it to stay in the crypts of the cervix for a few days.
The cervix develops a special mucosal plug which prevents bacteria from invading the Uterus and the growing fetus inside it. This plug of mucus comes out as the cervix dilates in labor.
Physiological functions of the Cervix
The Cervix dilates slightly during menstruation which allows the loosened endometrium to be shed. The same cervix stretches or rather contracts up to 10 centimeter in diameter to allow the head of the fetus to come out of it. This stretching and contractions of the Cervix is the reason behind the pains during menstruation and labor.
As proposed by Robin Baker and Mark A. Bellis, from the University of Manchester, the cervix convulses and the external Os dilates during sexual intercourse and orgasm to draw the semen into the Uterus to increase the chances of conception which was called as the upsuck theory of female orgasm which was also supported by Komisaruk, Whipple, and Beyer-Flores, in their book, The Science of Orgasm but then this theory has been found to be badly flawed as many of the experiments were found to be inconsistent and not meeting to the requite standards of research.