# Female Reproductive Embryology And Anatomy

Between **weeks 1 through 6**, female and male embryos are phenotypically indistinguishable. By **week 10**, the genitalia begin to have male and female characteristics. By **week 20**, phenotypic differentiation is complete. ![](https://f001.backblazeb2.com/file/wikiFiles/5J9ywMR.jpg)

The mesonephric duct, also known as the Wolffian duct, gives rise to the:

* **Seminal vesicles**
* **Epididymis**
* **Vas deferens** (or ductus deferens)
*   **Ejaculatory duct**

    ![](https://f001.backblazeb2.com/file/wikiFiles/fe1Jhvb.jpg)

    ![](https://f001.backblazeb2.com/file/wikiFiles/yTy1WWK.jpg)

Following dihydrotestosterone exposure, the urogenital sinus of the male embryo gives rise to:

* **Urinary bladder**
* **Prostatic urethra**
* **Membranous urethra**
* **Proximal penile urethra**
* **Bulbourethral glands of Cowper**
* **Prostate gland**

| DHT                                               |                       | Estrogen                         |
| ------------------------------------------------- | --------------------- | -------------------------------- |
| Glans penis, Corpus spongiosus, Corpus cavernosus | Genital Tubercle      | Glans clitoris, Vestibular bulbs |
| Cowper's gland, Prostate gland                    | Urogenital Sinus      | Bartholin gland, Skene gland     |
| Penile urethra, Ventral fold                      | Urogenital Folds      | Labia minora                     |
| Scrotum                                           | Labioscrotal Swelling | Labia majora                     |

![](http://i.imgur.com/t3T2WNb.jpg)

Following dihydrotestosterone exposure, the labioscrotal folds give rise to the **scrotum.**.

![](https://f001.backblazeb2.com/file/wikiFiles/djodplw.jpg)

Following dihydrotestosterone exposure, the genital tubercle gives rise to the:

* **Glans penis**
* **Corpus spongiosum**
* **Corpus cavernosum**

| DHT                                               |                       | Estrogen                         |
| ------------------------------------------------- | --------------------- | -------------------------------- |
| Glans penis, Corpus spongiosus, Corpus cavernosus | Genital Tubercle      | Glans clitoris, Vestibular bulbs |
| Cowper's gland, Prostate gland                    | Urogenital Sinus      | Bartholin gland, Skene gland     |
| Penile urethra, Ventral fold                      | Urogenital Folds      | Labia minora                     |
| Scrotum                                           | Labioscrotal Swelling | Labia majora                     |

![](http://i.imgur.com/t3T2WNb.jpg)

The ectoderm of the glans penis gives rise to the **distal penile urethra (spongy urethra).**

Following dihydrotestosterone exposure, the urogenital folds develop into the **proximal penile urethra and the ventral aspect of the penile shaft.**

| DHT                                               |                       | Estrogen                         |
| ------------------------------------------------- | --------------------- | -------------------------------- |
| Glans penis, Corpus spongiosus, Corpus cavernosus | Genital Tubercle      | Glans clitoris, Vestibular bulbs |
| Cowper's gland, Prostate gland                    | Urogenital Sinus      | Bartholin gland, Skene gland     |
| Penile urethra, Ventral fold                      | Urogenital Folds      | Labia minora                     |
| Scrotum                                           | Labioscrotal Swelling | Labia majora                     |

![](http://i.imgur.com/t3T2WNb.jpg)

The paramesonephric duct gives rise to the:

* **Fallopian tubes**
* **Uterus**
* **Cervix**
*   **Upper vagina**

    ![](https://f001.backblazeb2.com/file/wikiFiles/8yGgBnQ.jpg)

Following estrogen exposure, the female urogenital sinus gives rise to:

* **Lower 2/3 of the vagina**
* **Greater vestibular glands of Bartholin**
*   **Urethral glands of Skene**

    | DHT                                               |                       | Estrogen                         |
    | ------------------------------------------------- | --------------------- | -------------------------------- |
    | Glans penis, Corpus spongiosus, Corpus cavernosus | Genital Tubercle      | Glans clitoris, Vestibular bulbs |
    | Cowper's gland, Prostate gland                    | Urogenital Sinus      | Bartholin gland, Skene gland     |
    | Penile urethra, Ventral fold                      | Urogenital Folds      | Labia minora                     |
    | Scrotum                                           | Labioscrotal Swelling | Labia majora                     |

The female genital tubercle, following estrogen exposure, gives rise to the **clitoris and vestibular bulbs.**

| DHT                                               |                       | Estrogen                         |
| ------------------------------------------------- | --------------------- | -------------------------------- |
| Glans penis, Corpus spongiosus, Corpus cavernosus | Genital Tubercle      | Glans clitoris, Vestibular bulbs |
| Cowper's gland, Prostate gland                    | Urogenital Sinus      | Bartholin gland, Skene gland     |
| Penile urethra, Ventral fold                      | Urogenital Folds      | Labia minora                     |
| Scrotum                                           | Labioscrotal Swelling | Labia majora                     |

The female **labioscrotal folds** (or swellings) **around the genital tubercle** give rise to the labia majora. ![](https://f001.backblazeb2.com/file/wikiFiles/GysaGwQ.jpg)

Following estrogen exposure, the **urogenital folds** give rise to the labia minora. ![](https://f001.backblazeb2.com/file/wikiFiles/GysaGwQ.jpg)

Primary amenorrhea, with normal secondary sexual features, may develop as a result of **paramesonephric duct development anomalies.**

A bicornate uterus develops when the **paramesonephric ducts fails to fuse completely**, resulting in a two lumen uterus.

* **Upper end of the urogenital sinus** (continuous with the allantois, endodermal)
* **Mesonephric ducts** form the trigone (mesodermal)

**Uterine (Mullerian duct) anomalies**

c

**Bicornuate Uterus**:Condition where the uterus has two horns entering a common vagina.Etiology of bicornuate uterus is due to **partial fusion of the paramesonephric ducts.**&#x43;linically can present with urinary tract abnormalities and infertility.In pregnant women, bicornuate uterus is associated with increased risk of bleeding, spontaneous abortion, or premature delivery.

c

**Septate uterus:** Most common type of congenital uterine anomaly (\~55%)Results from **partial or complete failure of resorption of the uterovaginal septum after fusion of the para-mesonephric ducts.** Associated with a high rate of miscarriage and infertility. Treated with **septoplasty t**o form a single uterine cavity without perforating the uterus.

c

**Uterus didelphys: \*\***&#x43;ondition where there is complete duplication of the uterus, vagina and cervix. **Results from** complete failure of fusion of the para-mesonephric ducts. \*\*Pregnancy is possible for these individuals.
