Gonads

The gonads, the testes in men and the ovaries in women, are the body's primary sex organs and its primary sex hormone factories at once, producing the gametes, sperm and eggs, alongside the steroid hormones that shape puberty, fertility and much of secondary sexual development. Testosterone dominates in the testes and estrogen and progesterone in the ovaries, but the split is one of proportion rather than kind, since both organs manufacture all three hormones in different ratios. Neither gland acts on its own initiative. Both sit under the control of the pituitary above them, which releases luteinizing hormone and follicle stimulating hormone in patterns that drive testosterone production continuously in men and drive the monthly cycle of ovulation in women, a chain of command physiology calls the hypothalamic pituitary gonadal axis.

Hatha yoga's subtle body places the same function just below the navel. In Swami Satyananda Saraswati's synthesis in Asana Pranayama Mudra Bandha, the gonadal correspondence sits with Svadhisthana, the Sacral chakra, the center the tradition reads as sexuality, creativity and the flow of emotion, a broadening of the gland's reproductive role into a wider creative and emotional register the endocrine account does not itself make. The two readings, hormonal cascade and subtle energy center, are offered here as two distinct traditions of knowledge about the same organ, not as one confirming the other.