genital ridge

human anatomy

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Last updated

June 29, 2026

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The genital ridge is a crucial structure in early prenatal development, forming the foundation for the reproductive organs. It begins as a pair of longitudinal ridges alongside the mesentery. Primordial sex cells, originating in the yolk sac, migrate to these genital ridges to proliferate. Initially, both male and female reproductive systems develop from these ridges in an "indifferent stage," meaning the sex is not yet distinguishable. The gonads, which develop into testes or ovaries, are of mesodermal origin and are the first structures to form within the genital ridge.12

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human sexual activity
Development and change in the reproductive system
…ducts); externally there is a genital protrusion with a groove (urethral groove) below it, the groove being flanked by two folds (urethral folds). On either side of the genital protrusion and groove are two ridgelike swellings (labioscrotal swellings). Around the fourth week of life the gonads differentiate into either testes…
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…ducts); externally there is a genital protrusion with a groove (urethral groove) below it, the groove being flanked by two folds (urethral folds). On either side of the genital protrusion and groove are two ridgelike swellings (labioscrotal swellings). Around the fourth week of life the gonads differentiate into either testes…
Read More