1. Mesoderm-3rd week

2. Pronephros & mesonephros-4th week

3. Urogenital ridge 4th week

4. Urinary system-4th week

5. 4-5 week

6. Mesonephric vesicle

7. Mesonephric tubules

8. metanephros

9. Metanephric kidneys

10. Metanephric kidneys

11. 5th week

12. 6th-7th week

13. 8th-9th week

14. 12th week

15. Relocation of Kidneys 6th & 7th week

16. Relocation of Kidneys 8th & 9th week

17. Renal anomalies Renal agenesis – Potter Sequence
Renal dysplasias – multicystic dysplastic kidney
Cong. polycystic kidney D.
Autosomal dominant
Autosomal recessive
Duplication of ureter

18. Renal Anomalies Disorders due to malrotation
Often associated with ectopic kidneys
Malrotated kidneys
Supernumerary kidneys
Fused kidneys- crossed renal ectopia
Divided kidney with bifid ureter

19. Renal Anomalies Disorders due to positional changes
Accessory renal arteries
Accessory renal veins
Pelvic kidneys
Horseshoe kidneys
Pancake kidneys

20. Bladder Anomalies Urachal fistula Urachal sinus Urachal cyst
Exstrophy of bladder
Exstrophy of cloaca

21. Multiple Renal Arteries

22. Multiple Renal Veins

23. Unilateral Renal Agenesis

24. Pelvic Kidney

25. Malrotation of kidney

26. Crossed Renal Ectopia

27. Discoid Kidney

28. Supernumerary Kidney

29. Urachal Cyst

30. Urachal Sinus

31. Urachal Fistula

32. Development of gonads 4th week- primordial germ cells
5th week – Gonadal ridge
6th week – Incorporation of cells into gonadal cords
Upto 7th week – Indifferent gonad
Y- chrosomome- SRY gene for TDF in sex determining region of y ch.
Y chromosome has a testis determining effect on medulla of gonad
Type of gonad formed will further differentiate development of genital ducts and external genitalia

33. Development of gonad Mesothelium- (of post. Abd. Wall) Mesenchyme
Primordial germ cells-
large sperical cells among endoderm of yolk sac near allantois
Gonadal ridge-
mesothelial thickening on medial side of mesonephros + mesenchyme
Prim. Germ cells migrate along dorsal mesentery to gonadal ridge

34. Indifferent gonad Gonadal Ridge Gonadal cords
(Fingerlike epithelial cords)
Gonad consists of cortex & medulla
xy xx
Testis ovary

36. Indifferent Gonad

38. Indifferent Gonad

39. Differentiation of Gonads

40. Ovaries

41. Testis Condensation of cords Extension into medulla
Branching & anastomoses-rete testis
Tunica albuginea develops
Connection of cords with surface nis lost
S. tubules, T recti & rete T
Mesenchyme- interstitial cells in 8th wk- hormones
S tubules remain solid till puberty

42. Hormones in male
8-12 wk- peak of HCG --- Testosterone & androstenedion from Leydig cells
MIS / AMH from Sertoli cells

43. Mesonephric duct & tubules
Mesonephric tubules --- Efferent ductule + paradidymus in male
Epoophoron & paroophoron in female
M duct prox. Part --- duct of epididymus, appendix of epididymus
M duct distal part ---URETERIC BUD + ductus deferens, ejaculatory ducts & seminal gland
Appendix vesiculosa, duct of epoophoron & Gartner’s duct in female + URETERIC BUD

44. Descent of the Testis
The process vaginalis, (evagination of peritoneum), develops ventral to the gubernaculum and herniates through the abdominal wall along the path formed by the gubernaculum
The vaginal process carries extensions of the layers of the inguinal canal
In males these layers also form the coverings of the spermatic cord and testis
The opening in the transversalis fascia produced by the vaginal process becomes the deep inguinal ring
The opening created in the external oblique aponeurosis forms the superficial inguinal ring.

45. Descent of Testes Enlargement of the testes Atrophy of the mesonephroi
Atrophy of the paramesonephric ducts
Enlargement of the processus vaginalis
Enlargement of fetal pelvis
Trunk elongates
Androgens
Descend retroperitoneally
Gubernaculum
Increased intra abdominal pressure due to viscera .

47. Development of Inguinal Canals
The inguinal canals form pathways for the testes to descend from the abdomen into the scrotum
Develop in both sexes because of the indifferent stage
As the mesonephros degenerates, a ligament – the gubernaculum – descends on each side of the abdomen from the inferior pole of the gonad
The gubernaculum passes obliquely through the developing anterior abdominal wall at the site of the future inguinal canal
The gubernaculum attaches caudally to the internal surface of the labioscrotal swellings (future halves of the scrotum or labia majora).

53. Role of Gubernaculum Uncertain Forms a path for processus vaginalis
Anchors testes to scrotum
Guides its descent

54. Effects of descent of testes
Ductus deferens and vessels are carried with testes
Testis and ductus deferens are ensheathed by fascial extensions
Transversalis fascia ---- internal spermatic fascia
Internal oblique muscle and fascia --- cremasteric muscle and fascia
External oblique aponeurosis --- external spermatic fascia
In the scrotum the testis projects into the distal end of the processus vaginalis.

55. Cryptorchidism or Undescended Testes
Unilateral or bilateral
The testes fail to descend uptill the end of the first year
May fail to mature and sterility is common (bilateral)
Often histologically normal at birth, but failure of development and atrophy are detectable by the end of the first year
May be in the abdominal cavity or anywhere along the usual path of descent of the testis
Usually in the inguinal canal
Cause mostly unknown
Deficiency of androgen production by the fetal testes is an important factor
Increased risk of developing testicular cancer

56. Congenital Inguinal Hernia
Communication between the tunica vaginalis and the peritoneal cavity fails to close, a persistent processus vaginalis exists. A loop of intestine may herniate through it into the scrotum or labium majus
Hydrocele
Abdominal end of the processus vaginalis remains open but is too small to permit herniation of intestine. Peritoneal fluid passes into the patent processus vaginalis and forms hydrocele of the testis
If the middle part of the processus vaginalis remains open, fluid may accumulate and give rise to a hydrocele of the spermatic cord.

60. Ducts in male

61. Urinary bladder & Prostate

62. Hormonal Influence on Sex Differentiation
Testis
Mullerian inhibiting Testosterone
Substance (Sertoli cells) (Leydig cells)
Paramesonephric ducts suppressed Mesonephric ducts stimulated &
form epididymis & vas deferens
Ovary Estrogens
Paramesonephric ducts stimulated & External genitalia stimulated &
Form uterine tube, uterus, upper form labia, clitoris & lower portion of
portion of vagina vagina

63. Uterus & Vagina Three parts of paramesonephric ducts
Fimbriated end of fallopian tube
Body of fallopian tube
Uterovaginal primordium formation by union of paramesonephric ducts
Mesoderm forms broad lig. & parametrium
Uterovaginal primordium grows towards sinus tubercle in urogenital sinus
Sinovaginal bulbs & vaginal plate formation

65. Uterus &Vagina
9 Weeks 12 Weeks Newborn

66. Paramesonephric ducts & urogenital Sinus

67. Paramesonephric ducts & urogenital Sinus

68. Paramesonephric ducts & urogenital Sinus

69. Ducts in Female

70. Development in Female

71. Descent of the Ovaries Descent of the gonads in female is much less.
Ovaries move and settle just below the rim of the true pelvis.
Cranial genital ligament forms the suspensory ligament of the ovary, where as the caudal genital ligament forms the ligament of the ovary proper and the round ligament of the uterus. The later extends into the labia majora.

72. Adult Derivatives Male Embryonic Structure Female
Paramesonephric Duct Uterine tube
Uterus
Urinary bladder Urogenital Sinus Urinary bladder
Urethra Urethra
Prostatic gland Vagina
Bulbourethral glands Urethral & paraurethral glands
Greater vestibular glands
Sinus Tubercle Hymen
Penis Phallus Clitoris
Glans penis Glans clitoris
Corpora cavernosa penis Corpora cavernosa clitor.
Corpus spongiosum penis Bulb of vestibule
Ventral aspect of penis Urogenital Folds Labia minora
Scrotum Labioscrotal swellings Labia majora

73. Normal Uterus & Vagina

74. Double uterus & double vagina Uterus Didelphys & vagina duplex

75. Uterus didelphys &single vagina

76. Bicornuate uterus

77. Bicornuate uterus with rudimentary horn

78. Septate uterus

79. Unicornuate uterus

80. Ambiguous sex - Intersex
True Hermaphroditism- have testicular & ovarian tissue
Extremely rare, 70 % 46xx, 20% mosaicism, 10%46xy
presence of both testicular & ovarian tissue-nonfunctional ovotestes
phenotype variable with ambiguous external genitalia
Female Pseudohermaphroditism- have ovaries
46 xx, chromatin +,
exposure of excessive androgens to female fetus (C.Ad.Hyper.)
excessive progesterone in threatened abortion
maternal tumours
Male Pseudohermaphroditism- have testes
46xy, chromatin -,
external & internal genitalia are variable, testis rudimentary to normal
inadequate testosterone & MIS
Genetic defects in enzymes for production of testosterone

81. Ambiguous sex Androgen Insensitivity Syndrome Mixed Gonadal Dysgenesis
(testicular Feminization Syndrome)
46 xy, testes present, normal appearing female
Female external genitalia, Uterus & Ut. tubes rudimentary or absent, Vagina ends in a blind pouch
Normal breast development but no mensturation
Testes are in abdomen or ing. Canals
Resistance to testosterone at cellular level
Mixed Gonadal Dysgenesis
Testis on one side & undiff. gonad on other side
Internal genitalia female
External genitalia variable

83. External Genitalia Sexually undifferentiated stage.
Genital tubercle --- at the cranial end of the cloacal membrane.
Labioscrotal swellings and urogenital folds develop on each side of the cloacal membrane
The genital tubercle form a primordial phallus
Urorectal septum fuses with the cloacal membrane, it divides the cloacal membrane into
anal membrane
b. Ventral urogenital membrane.
The anal and urogenital membranes rupture forming the anus and urogenital orifice.
In female the urethra and vagina open into the vestibule.

84. Male External Genitalia
Masculanizaion of indifferent gonad by testosterone
Phallus forms penis
Urogenital folds form spongy urethra
Urogenital folds form walls of urethral groove on the ventral surface of penis
Urethral groove is lined by endodermal cells of urethral plate
Surface ectoderm fuses forming penile raphae & encloses spongy urethra
Cords forms at the tip and canalize to form urethral orifice
Labioscrotal swellings form the scrotum

85. External Genitalia Genital tubercle Urethral groove Urogenital orifice
Urogenital fold
Labioscrotal fold
Anus
7th Week Old Embryo 9th Week Old Embryo

86. External Genitalia of 12 Week Old Fetus
Glans penis
Glans clitoris
Urethral groove
Urethral orifice
Vestibule of vagina
Labia minora
Labia majora
Scrotal raphe
Scrotum
Anus
Male
Female

87. External Genitalia In Female
5 Week Embryo Newborn

88. Urethral orifice abnormalities
Epispadias
Urethra opens on dorsal surface
Urogenital sinus opens on dorsal surface
Urine is expelled at the dorsal surface of malformed penis
Hypospadias
The external urethral orifice is on the ventral surface of penis (penile hypospadias)
These defects result in failure of canalization of ectodermal cord or failure of fusion of urogenital folds