What is the squamocolumnar junction and transformation zone? The epithelium covering the cervix has two primitive epithelia during embryogenesis; the primitive squamous epithelium and the primitive columnar epithelium, the union of which is called the primitive squamocolumnar junction (OSCJ). Before puberty, the primitive squamocolumnar junction is located at or near the ectocervix. After puberty, the volume of the uterine body and cervix increases under the influence of ovarian hormone levels, and as the volume of the cervix increases, the columnar epithelium of the cervix moves down and turns outward. This downwardly displaced columnar epithelium is subjected to the acidic vaginal environment and pathogens and may gradually transform into “saprophytic” squamous epithelium (in abnormal cases into CIN), thus forming a “new” squamocolumnar junction between the “primitive” and “new” squamous epithelium. The area between the “original” and “new” squamocolumnar junction is called the transformation zone (TZ): also known as the migration zone. This zone of transformation is the focus of colposcopy. From the formation of the metaplastic epithelium and the transformation zone, it may be easy to understand why we are not concerned about seeing a simple submigrating columnar epithelium (“erosion”) of the cervix, but more about the fact that during the metaplastic process (when your cervix may become smooth), a small percentage of people will develop lesions. This may eliminate the misconception that the cervix is smooth, it’s fine, you don’t have to worry about it (this has become the mantra of many gynecologists), but your cervix is “rotten” and must be treated. I still say: whether your cervix is “celiac” or smooth, don’t jump to conclusions without being evaluated by a gynecologist, and don’t accept treatment for so-called “celiac disease” at will.