Anatomy of the Female Reproductive System

1. Xiu Xiu JiangEmail: janet418@sina.com.cn Ai Xia LiuEmail: wcumszzy@yahoo.com.cnTelephone (office): 87061501-1839Women’s Hospital, School of Medicine, Zhejiang University

2. Anatomy of the Female Reproductive System Jiang Xiu Xiu Women’s hospital, School of Medicine, Zhejiang University

3. Outline • Bony pelvis • Pelvic floor • External genitalia • Internal genitalia • Vascular, lymphatic and nervous system • Adjacent organs

4. Bony Pelvis Front view Rear view

5. Pelvis • A basin-shaped ring Latin word “basin” • To bear the weight of the upper body when sitting and standing • To contain and protect the pelvic organs

8. Pelvis • child-bearing and child-birth function in women. Female Male

9. Key factors of bony pelvis ------ related to child-birth • Size • Shape • Joint (movement ) • Ligament (relaxation)

10. Anatomy of the Bony Pelvis • Bones • Joints • Ligaments • Three planes of the pelvis • Types of the female pelvis

12. Bones Sacrum (1#) : 5 fused vertebrae Coxae : ilium (2#) Ischium (3#) pubis (4#) Coccyx : 3 fused cartilaginous bones

13. Bones sacral promontory Sacrum : 5 fused vertebrae • sacral promontory • superiormost portion of the sacrum • border of the pelvic inlet • can be touched • bone marker Coccyx : 4 fused cartilaginous bones

14. Bones Ischium (3#) Coxae : ilium (2#) pubis (4#) tuberosity ischial tuberosity --- marks the lateral boundary of the pelvic outlet.

15. Joints Sacro-iliac joint (SI) -minimal motion Sacro-coccygeal joint (SC) - slightly moveable (forward and backward). Symphysis pubis - slightly movable

16. Joints Symphysis pubis Greek word “growing together” • Absorb shock during walking. • Delivery of baby. gap of the symphysis pubis non-pregnant: 4-5mm Pregnant: less than 9mm

17. Joints Diastasis of the symphysis pubis result from: rapid birth; forceps delivery; prenatal; symptom: pelvic girdle pain --- involving 45% of all pregnant women and 25% of all women postpartum • symphysiotomy

18. Ligaments • Sacro-iliac joint • Anterior sacroiliac ligament • Interosseous sacroiliac ligament • Posterior sacroiliac ligament • Sacrotuberous ligament • Sacro-coccygeal joint • anterior sacrococcygeal ligament • posterior sacrococcygeal ligament • lateral sacrococcygeal ligaments • Intercornual sacrococcygeal ligament

19. Ligaments Sacrospinous ligament • Extend from the lateral border of the sacrum and coccyx to the ischial spine • A thin, triangular ligament • With sacrotuberous ligament, Closes off the greater sciatic notch to form the greater sciatic foramen and closes off the lesser sciatic notch to form the lesser sciatic foramen

20. Ligaments Sacrospinous ligament • Function • to prevent posterior rotation of the ilium with respect to the sacrum • Fixation site for pelvic organ prolapse • sacrospinous ligament suspension • the vaginal apex is suspended posteriorly and laterally to the ligament on either side or both sides

21. Ligaments Sacrotuberous ligament • Extend from the posterior aspect of the lower 3 sacral vertebrae to the ischial tuberosity • It is flat, and triangular in form; narrower in the middle than at the ends.

22. Boundary of pelvis • Border line posterior upper border of sacral promontory lateral iliopectineal line anterior upper border of pubis

23. Boundary of pelvis The female bony pelvis is divided into: False pelvis ( pelvis major ) ---above the border line and has no obstetric importance. True pelvis ( pelvis minor ) ---below the border line and related to the child -birth The bone delivery canal of childbirth

24. Planes of TruePelvis • inlet • outlet • mid-cavity

25. Planes of TruePelvis pelvic inlet is heart-shape, bounded by . posteriorly upper border of sacral promontory . laterally: iliopectineal line . anteriorly: upper border of pubis anteroposterior about 11cm. transverse about 13cm oblique about 12.75cm

26. Planes of TruePelvis • Mid-cavity It is a segment, the boundaries of which are: • the roof is the plane of pelvic inlet, • the floor is the plane of the plane of pelvic outlet, • anterior - the shorter symphysis pubis, • posterior - the longer sacrum. • Interspinous diameter = 10 cm • between the tips of ischial spines.

27. Planes of TruePelvis • Pelvic outlet: 2 triangular planes with 1 base which is the intertuberous diameter Anterior sagittal plane: apex - the lower border of the symphysis pubis. laterally: the ischiopubic arch Posterior sagittal plane: apex - the tip of the coccyx. Laterally - sacrotuberous ligament

28. Planes of TruePelvis Diameters of pelvic outlet Antero-posterior diameter =11.5cm from Sacro-coccygeal joint to the lower border of symphysis pubis. Transverse diameters (Bituberous diameter) = 9 cm between the inner aspects of the ischial tuberosities. Anterior sagittal diameter = 6 cm from the lower border of the symphysis pubis to the centre of the bituberous diameter. Posterior sagittal diameter = 8.5 cm from Sacro-coccygeal joint to the centre of the bituberous diameter.

29. Caldwell- Moloy Classificationof Pelvic Types (1933) Four types of female pelves were described. Actually, the majority of pelvis are mixed types.

30. Gynaecoid pelvis • It is the normal female type. • Inlet is slightly transverse oval. • Sacrum is wide with average concavity and inclination. • Side walls are straight with blunt ischial spines. • Sacro-sciatic notch is wide. • Subpubic angle is 90-100o. Ideal shape, best chances for normal vaginal delivery.

31. Anthropoid pelvis • It is ape-like type. • All anteroposterior diameters are long. • All transverse diameters are short. • Sacrum is long and narrow. • Sacro-sciatic notch is wide. • Subpubic angle is narrow (<900 ) • prominent ischial spines

32. Android pelvis • It is a male type. • Inlet is triangular or heart-shaped with anterior narrow apex. • Side walls are converging (funnel pelvis) • Projecting ischial spines. • Sacro-sciatic notch is narrow. • Subpubic angle is narrow <90o

33. Platypelloid pelvis • It is a flat female type. • All anteroposterior diameters are short. • All transverse diameters are long. • Sacro-sciatic notch is narrow. • Subpubic angle is wide

34. Pelvic floor

35. Pelvic floor • The tissues closing down the pelvic outlet (muscles and fasciae) Function - providing support for pelvic organs, e.g. the bladder, rectum, the uterus. - maintenance of continence Anterior part (urogenital triangle) urethra and vagina pass through Posterior part (anal triangle) rectum pass through

36. Pelvic floor Outer layer Bulbocavernosus muscle (球海绵体肌) Ischiocavernosus muscle (坐骨海绵体肌) Superficial transverse perineal muscle (会阴浅横肌) External anal sphincter (肛门外括约肌) mid layer urogenital diaphragm (泌尿生殖膈)

37. Pelvic floor Inner layer(pelvic diaphragm 盆膈) • the main support of the pelvic floor • formed by the levator ani and coccygenus muscles and covering fasciae. • Levator ani: （肛提肌) pubococcygenus (耻尾肌), iliococcygenus (髂尾肌), puborectalis (坐尾肌)

38. PC IC

39. Levator ani Pubococcygenus (PC ) -a hammock-like muscle -stretches from the pubic bone to the coccyx (tail bone) -controls urine flow and position the baby's head during childbirth. Iliococcygenus (IC) - arises from the ischial spine, super ramus of the pubis, and is attached to the coccyx - Help for vaginal contraction Puborectalis (PR) sphincter ani externus - arise from the lower part of the symphysis pubis,and the superior fascia of the urogenital diaphragm , meet with the corresponding fibers of the opposite side around the lower part of the rectum, and form for it a strong sling. - Relaxation reduces the angle between rectum and anus, allowing defecation in conjunction with relaxation of the internal and external sphincters.

40. Pelvic floor • Perineum general conception: the tissues closing down the pelvic outlet Clinical conception: the tissues between vaginal and anus. -thickness: 3-4cm - the outlayer support for pelvic floor

41. SUMMARY • Bones • Joints • Ligaments • planes of the pelvis • Types of the female pelvis • Pelvice floor

42. END