1. Histo 3: The Female Reproductive System: Uterus and Vagina Per Brodal Institutt for medisinske basalfag Universitetet i Oslo 9th Semester 2008

2. The Uterus Cervix uteri Canalis cervicis Internal os External os Corpus uteri Isthmus Vagina 2 P. Brodal 2008

3. Corpus uteri (cross section) Perimetrium (serosa and subserosa) Myometrium Endometrium Vessels in the parametrium 3 P. Brodal 2008

4. Menstrual Cycle 1 5 14 28 Days MenstruationProliferative phase Secretory phase Estrogen Progesterone 4 P. Brodal 2008

5. Layers of the Endometrium PROLIFERATIVE PHASE SECRETORY PHASE Muscular layer (myometrium) Basal layer Functional layer (functionalis) Spiral artery Straight artery (basal artery) 5 P. Brodal 2008

6. The endometrium - The mucosa of the uterus  Epithelium: Simple columnar epithelium (surface and glands)  Stroma: Mesenchyme-like loose connective tissue  Specialized to enable the blastocyst to implant and grow  Forms the maternal portion of the placenta 6 P. Brodal 2008

7. Early Proliferative Phase Endometrium Myometrium Basal layer Gland Bundles of smooth muscle cells 7 P. Brodal 2008

8. Late Proliferative Phase 8 P. Brodal 2008

9. Late Proliferative Phase 9 P. Brodal 2008

10. Secretory Phase Functional layer Basal layer 10 P. Brodal 2008

11. Secretory Phase 11 P. Brodal 2008

12. Secretory Phase Hypertrophy of glandular cells and Edema Spiral artery 12 P. Brodal 2008

13. Menstruation  Spasmodic contractions of the spiral arteries due to discontinuation of progesterone  Ischemia – loss of contractility  Bleeding – 30-50 ml  Rests of the functional layer and blood – not coagulating  Takes place at various sites in a sequence  Epithelization takes place continuously after shedding 13 P. Brodal 2008

14. The Cervix Nabothian cysts 14 P. Brodal 2008 Fibromuscular stroma Mucus producing epithelium Transition between cylindrical and stratified squamous epithelium

15. Cervix 15 P. Brodal 2008

16. Cervical Mucosa Mucus plug in the cervix – viscous except at the time of ovulation 16 P. Brodal 2008

17. The cervical mucosa may extend to the vaginal surface of the portio ”Erosion” Most cervical carcinomas arise from the squamous epithelium 17 P. Brodal 2008

18. The Myometrium 18 P. Brodal 2008 Bundles of smooth muscle fibers Coiled arteries

19. Organization of the myometrium DURING PREGNANCY:  The muscle fibers increase in length 7- 10 fold  The fibers unwind  Abundant connective tissue allows movement of the smooth muscle bundles  The growth of the muscle fibers occurs first at the site of implantation 19 P. Brodal 2008

20. Uterus in Pregnancy and after Delivery Months of pregnancy 6 9 10 Benninghoff/Goerttler Days after delivery 2 5 9 First mainly growth of muscle fibers, thereafter mainly stretching Involution 20 P. Brodal 2008

21. The vagina  Stratified squamous epithelium (non-keratinized), 20-30 layers  Lamina propria with venous plexuses  No glands  Two layers smooth muscle, mixed with many elastic fibers  Very distensible  Rich sensory innervation of the lamina propria and muscular layer but few pain fibers from the upper part  pH 4-5 due to lactobazillus acidophilus 21 P. Brodal 2008

22. Pelvic floor (female monkey) 22 P. Brodal 2008 Urethra Vagina Rectum

23.  Follicular phase: The thickness of the epithelium increases The superficial cells accumulate glycogen and become strongly eosinophilic with pyknotic nuclei Exfoliation of cells increases and reaches a maximum at ovulation  Luteal phase: The thickness decreases The cells are more basophilic and are exfoliated in clusters Cyclic Changes of the Vaginal Epithelium 23 P. Brodal 2008

24. Vaginal Smears Parabasal cells Intermediate Superficial Section Smear Presence of estrogen is necessary for surface epithelial cells to become eosinophilic 24 P. Brodal 2008 Follicular phase Luteal phase

25. Cervical Smear Cylindrical cells 25 P. Brodal 2008