Gonadal ridge
（重定向自Genital ridge）
![](/Images/godic/202501/15/Gray11061506.png")
![A.—Diagram of the primitive urogenital organs in the embryo previous to sexual distinction.
* 3. Ureter.
* 4. Urinary bladder.
* 5. Urachus.
* cl. Cloaca.
* cp. Elevation which becomes clitoris or penis.
* i. Lower part of the intestine.
* ls. Fold of integument from which the labia majora or scrotum are formed.
* m, m. Right and left Müllerian ducts uniting together and running with the Wolffian ducts in gc, the genital cord.
* ot. The gonadal ridge from which either the ovary or testis is formed (upper right).
* ug. Sinus urogenitalis.
* W. Left Wolffian body.
* w, w. Right and left Wolffian ducts.](/Images/godic/202501/15/Gray1110-11506.png")
In embryology, the gonadal ridge (or genital ridge) is the precursor to the gonads. The gonadal ridge initially consists mainly of mesenchyme and cells of underlying mesonephric origin. Once oogonia enter this area they attempt to associate with these somatic cells. Development proceeds and the oogonia become fully surrounded by a layer of cells (pre-granulosa cells).