Genitofemoral n.

The genitofemoral nerve refers to a human nerve that is found in the abdomen. Its branches, the genital branch and femoral branch supply sensation to the upper anterior thigh, as well as the skin of the anterior scrotum in males and mons pubis in females. (The femoral branch is different from the femoral nerve, which also arises from the lumbar plexus).

The genitofemoral nerve originates from the upper L1-2 segments of the lumbar plexus. It passes downwards and emerges from the anterior surface of the psoas major muscle. The nerve continues downwards and divides into two branches, the genital branch and the femoral branch.

The genital branch passes through the deep inguinal ring and enters the inguinal canal. In men, the genital branch continues down and supplies the scrotal skin. In women, the genital branch accompanies the round ligament of uterus, terminating in the skin of the mons pubis and labia majora.

The femoral branch passes underneath the inguinal ligament, traveling adjacent to the external iliac artery, and supplying the skin of the upper, anterior thigh.

The genitofemoral nerve is responsible for both the sensory (femoral branch) and motor portions (genital branch) of the cremasteric reflex, which describes contraction of the cremasteric muscle when the skin of the superior medial part of the thigh is touched.