Penis Development

Embryology - 4 Sep 2026 Expand to Translate
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Introduction

Week 9, the indifferent stage of external genitalia.

The external male genitalia consists of the penis and scrotum containing the testis.

Mesonephric duct = Wolffian duct.

Historic Embryology - Genital
General: 1901 Urinogenital Tract \| 1902 The Uro-Genital System \| 1904 Ovary and Testis \| 1912 Urinogenital Organ Development \| 1914 External Genitalia \| 1921 Urogenital Development \| 1921 External Genital \| 1942 Sex Cords \| 1953 Germ Cells \| Historic Embryology Papers \| Historic Disclaimer
Female: 1904 Ovary and Testis \| 1904 Hymen \| 1912 Urinogenital Organ Development \| 1914 External Genitalia \| 1914 Female \| 1921 External Genital \| 1927 Female Foetus 15 cm \| 1927 Vagina \| 1932 Postnatal Ovary
Male: 1887-88 Testis \| 1904 Ovary and Testis \| 1904 Leydig Cells \| 1906 Testis vascular \| 1909 Prostate \| 1912 Prostate \| 1914 External Genitalia \| 1915 Cowper’s and Bartholin’s Glands \| 1920 Wolffian tubules \| 1935 Prepuce \| 1935 Wolffian Duct \| 1942 Sex Cords \| 1943 Testes Descent \| Historic Embryology Papers \| Historic Disclaimer

Some Recent Findings

Complex epithelial remodeling underlie the fusion event in early fetal development of the human penile urethra^[1] "The opening zipper progresses from proximal to distal along the shaft of the penis and clitoris into the glans in identical fashion in both sexes. The closing zipper mechanism is active only in males and is not a single process but rather a series of layered fusion events, uniquely different from the simple fusion of two epithelial surfaces as occurs in formation of the palate and neural tube."
Modifications of erectile tissue components in the penis during the fetal period^[2] "The penile erectile tissue has a complex microscopic anatomy with important functions in the mechanism of penile erection. The knowledge of such structures is necessary for understanding the normal physiology of the adult penis. Therefore, it is important to know the changes of these penile structures during fetal development. This study aims to analyze the development of the main components of the erectile tissue, such as collagen, smooth muscle fibers and elastic system fibers, in human fetuses. We found strong correlation between the elements analyzed with fetal age, both in corpus cavernosum and corpus spongiosum. The growth rate of these elements was more intense during the second trimester (13 to 24 WPC) of gestation, both in corpus cavernosum and in corpus spongiosum. There is greater proportional amount of collagen in the corpus spongiosum than in corpus cavernosum during all fetal period. In the corpus spongiosum, there is about four times more collagen than smooth muscle fibers and elastic system fibers, during all fetal period studied. "

More recent papers
This table allows an automated computer search of the external PubMed database using the listed "Search term" text link. This search now requires a manual link as the original PubMed extension has been disabled. The displayed list of references do not reflect any editorial selection of material based on content or relevance. References also appear on this list based upon the date of the actual page viewing. References listed on the rest of the content page and the associated discussion page (listed under the publication year sub-headings) do include some editorial selection based upon both relevance and availability. More? References \| Discussion Page \| Journal Searches \| 2019 References \| 2020 References Search term: Penis Embryology <pubmed limit=5>Penis Embryology</pubmed>

Movies

‎‎Male External

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‎‎Testis

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‎‎Testis Descent

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Mesonephic Duct Development

The paired mesonephic ducts (Wolffian ducts) go through a series of developmental changes to form the male internal genital tract.

Initiation

Invagination

Elongation

Links:

Foreskin Development

Foreskin development occurs during the second trimester.^[3]

GA week 12 (Week 10) - ectoderm circular invagination at the glandular periphery now grows ventrally.
GA week 13 (Week 12) - glans partially covered by the foreskin.
GA week 16-17 (Week 14-15) - glans almost completely covered by the foreskin.
GA week 18-19 (Week 16-17) - complete foreskin was formed.
GA week 20 (Week 18) - entirely involves the glans.

Postnatal Development

Abnormalities

Hypospadia

External urethral opening on the ventral surface of penis, can extend back into scrotum. Abnormality due to failure of genital fold fusion during fetal development of the male external genitalia.

Hypospadia Classification	Meatus Opening
Anterior	on inferior surface of glans penis
Coronal	in balanopenile furrow
Distal	on distal third of shaft
Penoscrotal	at base of shaft in front of scrotum
Scrotal	on scrotum or between the genital swellings
Perineal	behind scrotum or genital swellings
Links: Genital Abnormalities \| Penis Development

Epispadias

Uncommon abnormality associated with the penis, 1 in 30,000 infant males, external urethral opening on the dorsal surface of penis.

Endocrine Disruptors

Endocrine disruptors in female reproductive tract development and carcinogenesis.^[4]

Additional Images

Historic

References

↑ <pubmed>27397682</pubmed>
↑ <pubmed>25170760</pubmed>| PLoS One.
↑ Favorito LA, Balassiano CM, Costa WS & Sampaio FJ. (2012). Development of the human foreskin during the fetal period. Histol. Histopathol. , 27, 1041-5. PMID: 22763876 DOI.
↑ <pubmed>19709900</pubmed>

Reviews

Articles

Wisniewski H & Terry RD. (1968). Further studies on experimental neurofibrillary tangles. J. Neuropathol. Exp. Neurol. , 27, 149-50. PMID: 5690451

Historic Embryology - Genital
General: 1901 Urinogenital Tract \| 1902 The Uro-Genital System \| 1904 Ovary and Testis \| 1912 Urinogenital Organ Development \| 1914 External Genitalia \| 1921 Urogenital Development \| 1921 External Genital \| 1942 Sex Cords \| 1953 Germ Cells \| Historic Embryology Papers \| Historic Disclaimer
Female: 1904 Ovary and Testis \| 1904 Hymen \| 1912 Urinogenital Organ Development \| 1914 External Genitalia \| 1914 Female \| 1921 External Genital \| 1927 Female Foetus 15 cm \| 1927 Vagina \| 1932 Postnatal Ovary
Male: 1887-88 Testis \| 1904 Ovary and Testis \| 1904 Leydig Cells \| 1906 Testis vascular \| 1909 Prostate \| 1912 Prostate \| 1914 External Genitalia \| 1915 Cowper’s and Bartholin’s Glands \| 1920 Wolffian tubules \| 1935 Prepuce \| 1935 Wolffian Duct \| 1942 Sex Cords \| 1943 Testes Descent \| Historic Embryology Papers \| Historic Disclaimer

Glossary Links

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Cite this page: Hill, M.A. (2026, September 4) Embryology Penis Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Penis_Development

What Links Here?

[PMID27397682-1] <pubmed>27397682</pubmed>

[PMID25170760-2] <pubmed>25170760</pubmed>| PLoS One.

[PMID22763876-3] Favorito LA, Balassiano CM, Costa WS & Sampaio FJ. (2012). Development of the human foreskin during the fetal period. Histol. Histopathol. , 27, 1041-5. PMID: 22763876 DOI.

[4] <pubmed>19709900</pubmed>

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