Bradley Manning, the U.S. Army private who was sentenced Aug. 21 to 35 years in a military prison for releasing highly sensitive U.S. military secrets, is seeking gender reassignment. Here’s how gender reassignment works:

Converting male anatomy to female anatomy requires removing the penis, reshaping genital tissue to appear more female and constructing a vagina.

An incision is made into the scrotum, and the flap of skin is pulled back. The testes are removed.

A shorter urethra is cut. The penis is removed, and the excess skin is used to create the labia and vagina.

People who have male-to-female gender-reassignment surgery retain a prostate. Following surgery, estrogen (a female hormone) will stimulate breast development, widen the hips, inhibit the growth of facial hair and slightly increase voice pitch.

Female-to-male surgery has achieved lesser success due to the difficulty of creating a functioning penis from the much smaller clitoral tissue available in the female genitals.

The uterus and the ovaries are removed. Genital reconstructive procedures (GRT) use either the clitoris, which is enlarged by hormones, or rely on free tissue grafts from the arm, the thigh or belly and an erectile prosthetic (phalloplasty).

Breasts need to be surgically altered if they are to look less feminine. This process involves removing breast tissue and excess skin, and reducing and properly positioning the nipples and areolae. Androgens (male hormones) will stimulate the development of facial and chest hair, and cause the voice to deepen.

Reliable statistics are extremely difficult to obtain. Many sexual-reassignment procedures are conducted in private facilities that are not subject to reporting requirements.

The cost for female-to-male reassignment can be more than $50,000. The cost for male-to-female reassignment can be $7,000 to $24,000.

Between 100 to 500 gender-reassignment procedures are conducted in the United States each year.