Module 4: Embryology Of The Female Reproductive System Flashcards
The genital and urinary system develop at what rate?
The same time
Both the genital and urinary system arise from what?
The Mesoderm that initially takes the form of the wolffian body
The sex of the embryo is determined when?
At the fertilization by the sperm
The genital tracts of both males and females are the same until when?
Up until 7 weeks
The germ cells that sex the embryo originate where?
Yolk sac
The germ cells differentiate from what? And migrate where?
From other germ cells and migrate to the gonadal ridge
What is another name for the mesonephros?
Wolffian ducts
In males, hormones cause the differentiation and growth of what? This inhibits what?
Wolffian ducts and inhibit the Müllerian ducts
In males, primitive sex cords proliferate and what else?
Give rise to testes
What is another name for Müllerian ducts?
Paramesonephric ducts
What are the Müllerian ducts paired with?
Wolffian ducts
In females, with no Male hormones the Wolffian ducts do what?
Regress and the Müllerian ducts are stimulated by maternal hormones (Estrogen)
When the Wolffian ducts regress what forms? 3
- Fallopian tubes
- Uterus
- Proximal vagina
In females, the sex cords break up and are replaced by what?
Vascular storms, which forms ovarian medulla
In females, a second group of cords which are named what? Do what?
Cortical cords, they develop, forming the ovarian cortex
The vagina has how many origins?
Dual origins
What are the dual origins of the vagina?
- The upper portion of the Müllerian ducts
- The lower portion from the urogenital sinus
If the fusion of the dual origins of the vagina is not complete or incomplete what happens?
An impeforate hymen will result
The cranial or the upper proximal portion of the Müllerian ducts form what?
Fallopian tubes
The caudal ends of the Müllerian ducts form what?
The uterus and upper vagina
What are the three classifications of abnormal Müllerian duct development?
- Arrested development
- Failure of fusion
- Incomplete resorption
If one or both Müllerian ducts do not develop what happens? 2
- Uterine aphasia
- Unicornuate uterus
What is Mayer-Rokitansky-Kuster-Hauser?
Complete agenesis of uterus and vagina
What is another way to reference Mayer-Rokitansky-Kuster-Hauser?
MRKH syndrome
What happens in arrested development
If one or both Müllerian ducts do not develop
What happens when there is a failure to fuse?
The Müllerian ducts develop but fail to fuse together
What are some results of failure to fusion? 4
- Uterus didelphys
- Uterus Bicornis Bicollis
- Uterus Bicornis unicorns
- Uterus Arcturus
Which failure to fusion is most commonly viewed on ultrasound?
Uterus Bicornis unicollis
What is a Bicornuate uterus?
Serous all indent (outside of uterus) is greater than 10 mm at Fundus
What happens during incomplete resorption?
The Müllerian ducts fuse but the septum is not reabsorbed
What are two examples of incomplete resorption?
- Uterus septus (full)
- Uterus Subseptus (partial)
Which incomplete resorption is the most common occurring of all mullerian anomalies?
Uterus subseptus (partial)
Which incomplete resorption example has the poorest reproductive outcome?
Uterus subseptus (partial)
Why is Uterus subseptus (partial) the poorest abnormal Müllerian development?
The Septus does not have a good vascular supply to support pregnancy
The Serosal (outside) surface of the septa the uterus has what kind of contour?
Normal
For a septate uterus the indentation of what appears where?
Indentation of greater than 1cm of the endometrium from the fundus
IN a septate uterus the septum runs the length of what?
The entire endometrial canal
In a subseptate uterus the septum is where?
Only partial down the canal
What is diethylstilbestrol exposure?
DES was a drug prescribed to stop spontaneous abortion (miscarriage)
What does DES do?
Interferes with the development of the mesenchyme of the genital tract in uterine
What is DES associated with?
Reproductive complications- depending on the amount of DES ingested, and the gestation age of the fetus at the time of exposure
When was DES discontinued?
1971 after it was proved to cause clear cell carcinoma of vagina
Those exposed to DES has a higher risk of what?
Breast cancer (2x as likely)
What do DES exposed women have?
Uterine anomalies
How common is a T shaped uterus?
31%
The T shaped uterus has a uterine cavity that has what volume? This results in what?
Uterine cavity has less volume and increased risk of spontaneous abortions, ectopic pregnancies and preterm deliveries
How is a T-shaped uterus best diagnosed?
With hysterosalpingograms?
Failures to fuse will always have a what?
A divit at the tops above the fundus
