This document provides an overview of the development of the female reproductive system from an indifferent embryo stage through the formation of the internal and external genital organs. It discusses how in early development, the embryo possesses two pairs of genital ducts and is sexually indifferent. Later, the müllerian ducts form the internal female organs like the uterus and fallopian tubes, while the external genitalia are formed from other structures. The lecture aims to explain reproductive tract anomalies that can result from disturbances during embryonic development of the female reproductive system.

1. Program: B.Sc Nursing, 3rd Year
BNSG-501 MSN
Unit No.4.
Topic- Indifferent embryo
Lecture No. 6
Dr. Sudharani B Banappagoudar
Professor, SONS/OBG
1
BNSG 501

2. Outline
 Introduction
 Female reproductive system
 Indifferent embryo
 Development of genital ducts
 Learning outcomes
 Exercise
 References
2
BNSG 501

3. TOPIC-REPRODUCTIVE TRACT ANAMOLIES
INTRODUCTION
FEMALE REPRODUCTIVE SYSTEM
INDIFFERENT EMBRYO
DEVELOPMENT OF GENITAL DUCTS
3
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

4. Objectives
• The student will be able to Explain
• Introduction
 Female reproductive system
 Indifferent embryo
 Development of genital ducts
4
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R2>
BNSG 501

5. 5
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

6. Congenital malformations of the female genital tract may be the result of a clear disturbance in one
stage of embryonic development, or result from disturbances in more than one stage of normal
formation. There are therefore extremely wide anatomical variations and a large number of
combinations of congenital malformations of the female genital tract.
INTRODUCTION
6
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

7. The human female reproductive system is divided into two :- internal
genital organs and external genital organs.
Internal genital organs are
 Vagina
 Cervix
 Uterus
 Fallopian tubes
 ovaries
Female Reproductive System
7
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

8. 8
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

9. The external genital organs are
 Mons pubis
 Labia majora
 Labia minora
 Clitoris
 Hymen
 Vestibular gland (Bartholin’s glands)
 Urethral orifice
 Vaginal orifice
 Perineum
 Anus
9
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

10. 10
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

11. Vagina: The vagina is a canal that joins the cervix (the lower part of uterus) to the outside of the
body. It also is known as the birth canal.
Uterus (womb): The uterus is a hollow, pear-shaped organ that is the home to a developing
fetus. The uterus is divided into two parts: the cervix, which is the lower part that opens into
the vagina, and the main body of the uterus, called the corpus. The corpus can easily expand to
hold a developing baby. A channel through the cervix allows sperm to enter and menstrual
blood to exit.
Internal Genital Organs
11
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

12. 12
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

13. Ovaries: The ovaries are small, oval-shaped glands that are located on either side of the uterus.
The ovaries produce eggs and hormones.
13
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

14. Fallopian tubes: These are narrow tubes that are attached to the upper part of the uterus and serve
as tunnels for the ova (egg cells) to travel from the ovaries to the uterus.
Conception, the fertilization of an egg by a sperm, normally occurs in the fallopian tubes. The
fertilized egg then moves to the uterus, where it implants into the lining of the uterine wall.
14
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

15. 15
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

16. Cervix: The Cervix (the lower part of the uterus that protrudes into the vaginal canal) has an
orifice that allows passage of menstrual flow form the uterus and passage of sperm into the
uterus.
16
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

17. Genotype of embryo 46XX or 46XY is established at fertilization.
At 1-6 wks it is sexually indifferent or undifferentiated stage; that is genetically female and male
embryos are phenotypically indistinguishable.
ATWeek 7 begins phenotypic sexual differentiation.
Week 12 female or male characteristics of external genitalia can be recognized.
Week 20 phenotypic differentiation is complete.

18. In utero photograph of a 56-day embryo showing continued growth of the genital tubercle and
elongation of the urethral folds that have not yet initiated fusion. The genital swellings remain
indistinct.
18
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

19. Both male and female embryos have two pairs of genital ducts
The mesonephric ducts (wolffian ducts) play an important role in the development of the male
reproductive system
The paramesonephric ducts (mullerian ducts) have a leading role in the development of the
female reproductive system
Till the end of sixth week, the genital system is in an indifferent state, when both pairs of genital
ducts are present
Development of Genital Ducts

20. 20
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

21.  Mullerian ducts form as buds of coelomic epithelium .
 Grows downward & lateral to corresponding wolffian ducts.
 Turn inwards & crosses anterior to it joining its fellow from opposite side.
21
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

22. Consists of
• Upper vertical part lateral to wolffian
duct → fallopian tube.
 Middle horizontal part crossing
walffian duct → remaining part of
fallopian tube.
 Lower vertical part fusing to opposite
part → uterus, cervix, upper 1/3rd of
vagina.
 In forming the uterus, the mullerian
ducts fuses from below upwards
22
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

23. REABSORPTION OF SEPTUM
After the lower Mullerian ducts fuse, a central septum is present, which
subsequently must be reabsorbed to form a single uterine cavity and
cervix. Failure if reabsorption between 14th and 18th week is the cause of
septate uterus.

24.  Develops in 3rd month of embryoniclife.
 From lower end of uterovaginal canal (mullerian duct) & urogenital sinus.
 Uterovaginal canal fuses with sinovaginal bulb (develops from posterior aspect of urogenital sinus)
forming vaginal plate.
 Later canalizes to form vaginal canal.
VAGINA
24
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

25. 25
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

26. Upper 1/3rd develops from Mullerian ductt mesodermal
Lower 2/3rd develops from vaginal plate – endodermal
 Incomplete breakdown of the junction between the bulbs and the urogenital sinus proper
leaves the hymeneal membrane.
26
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

27. 27
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

28.  Each germ cell, now become known as Oogonia, is surrounded by a single
layer of epithelial cells
The oogonia are transformed into primary oocytes as they enter the 1st meiotic division and
arrest in prophase until puberty and beginning of ovulation.
Around the 20th week of gestation the ovary contains about 7 million germ cells.
Degeneration and atresia begins around 20 weeks and by birth approximately 20 million germ
cells remain.
By the fourth month:
28
<SELO: 1,3,4,6,8,10,20>
<Reference No.: R1,R3>
BNSG 501

29. EXERCISE
29
BNSG 501
 Explain the Female reproductive system, Indifferent embryo, Development of genital ducts

30. LEARNING OUTCOMES
BNSG 701 30
The student explain about
 Introduction
 Female reproductive system
 Indifferent embryo
 Development of genital ducts

31. Student effective learning outcome
1.Application of concepts of topic & it’s technological application.
2. Critical and innovative thinking skills
3.Life long learning ability
4.Ability to observe and develop sense making , logical skills for abstract concepts.
5.Ability to understand subject related concepts clearly along with contemporary issues
6.Ability to collaborate
7.Ability to be a lifelong learner
BNSG 501 31

32. REFERENCES
• Sara Howard (2013) Midwifery retrieved April 17, 2014 from www.powershow.com
• CordeliaS.H.(2014) A brief History Of Midwifery in America. Retrieved April 11, 2014 from
wholisticmaternalnewbornhealth.org/professio nal-education/history-of-midwifery
• midwifeinsight.com/articles/a-short-history-of- midwifery/,retrieved April 18,2014.
32
BNSG 501

33. BNSG 501 33