Sample Taker Training Anatomy & Physiology of Pelvic Organs
Median Section Of Female Pelvis
External Female Genitalia - vulva
Female Reproductive Tract - Anterior View
UTERUS Located centrally within pelvic cavity Hollow muscular organ 7.5cm long Consists of: –Upper body –Lower neck (Cervix) Walls separated by slit like space (uterine cavity) Body CervixUterine Cavity
Uterine cavity Lined by endometrial epithelium Undergoes cyclical changes in thickness Upper third of epithelium will shed during menstruation
CERVIX Neck of the womb Has an internal and external os Can be divided into 2 parts –Endocervix –Ectocervix –These are lined by different types of cells Endocervix Ectocervix
Endocervix Tall columnar surface epithelium arranged into folds (crypts)
Ectocervix Ectocervix: Covered by a multi-layered Squamous Epithelium
Squamo-columnar junction Endocervical cells - delicate Squamous cells - protective Squamo-columnar junction
EndocervixEctocervix
Squamo-columnar Junction
Squamo-columnar junction
VAGINA Covered by protective stratified squamous epithelium (epithelium is continuous with ectocervix)
The Menstrual Cycle 28 days 4 phases: –Menstruation –Proliferative phase –Ovulation –Secretory phase Oestrogen & progesterone levels fluctuate
The menstrual cycle
Squamous Epithelium Fully mature if high levels of Oestrogen
Clinical data Different cells may be seen depending on hormone levels (oestrogen & progesterone).
Cervix Changes to the position of the cervical epithelia occur especially at puberty and during pregnancy The uterus increases in size and this pushes down on the cervix Ectropion can occur at these times
The endocervical cells are pushed out to lie on the ectocervix Ectropion NormalEctropion
Ectropion/’Erosion’
Metaplasia The endocervical cells are transformed into squamous cells through the process of squamous metaplasia, a protective mechanism.
Squamous Metaplasia Delicate endocervical epithelium is replaced by squamous epithelium through a process called metaplasia. The area where metaplasia takes place is called the transformation zone
Squamous Metaplasia New squamo- columnar junction Old squamo-columnar junction Endocervical crypts remain beneath the ‘new’ squamous epithelium Nabothian follicles can sometimes develop
Transformation Zone The area where metaplasia occurs is called the TRANSFORMATION ZONE This is an unstable area where Cervical Abnormalities can arises The whole of the TZ must be sampled when a cervical smear is taken
Metaplasia Squamous epithelium Crypt openings in transformation zone Squamo-columnar junction Everted columnar epithelium (‘ectropion’) Transformation zone
Transformation Zone Cells Endocervical cells Metaplastic cells Can be identified on cytology sample Indicates good quality Should be present in most samples from women aged 25-50
Post-menopausal cervix Transformation Zone SCJ Transformation zone may not be visible in a post-menopausal cervix. Tip of broom may reach it in some cases.