The labia majora is a part of the vulva. The labia majora are the two outermost folds of skin. The skin over the labia majora contains hair and surrounds the clitoris, urethra, and vaginal opening.
The labia minora is a part of the vulva (external portion of the female genital organs), the labia minora are the two innermost folds of skin between the labia majora. The skin over the labia minora does not contain hair and surrounds the clitoris, urethra, and vaginal opening.
Lactation is the process of milk secretion that occurs in female mammals in order to provide nourishment and immune protection for offspring. Lactation is dictated by the production and release of specific hormones designed to develop the duct system of the breasts which begins around the second trimester of pregnancy.
Lactotropes are specialized cells in the anterior pituitary that produce the hormone prolactin.
Lanugo is a soft downy hair that grows on the fetus as a normal part of gestation. Lanugo appears by about the 5th month of gestation and is shed at around 33 to 36 weeks of gestational age. Although lanugo can be seen on the shoulders of a newborn, more extensive presence on a newborn is a sign of premature birth. Most lanugo still present on newborns, commonly referred to as “peach fuzz”, is shed within a couple weeks after birth.
Laparoscopy is key-hole surgery procedure that allows surgeons to see inside the abdomen (tummy). This type of surgery is very useful for seeing the female reproductive organs (uterus, ovaries, etc.). It normally requires a general anesthetic, but patients can often go home the same day as surgery.
Leydig cells are cells within the male testes that produce the hormone testosterone in response to luteinizing hormone (LH) from the pituitary. Leydig cells are found within the interstitial space of the testes, between the seminiferous tubules.
Libido is a term for sexual desire or the degree of sexual appetite.
Libido is the psychological and emotional energy attached to the sex drive. Low libido is associated with a decreased desire to have sexual intercourse.
The limbic system is comprised of a set of structures located in the brain involved in the control of emotion, behavior, and memory.
Lobular is a term used to describe lobules or glands found in breast tissue that produce milk. Lobular is a descriptive of abnormal breast cell growth that begins in the lobules, e.g., lobular carcinoma and lobular neoplasia.
The luteal phase is the portion of the menstrual cycle in which the corpus luteum forms and matures. This half of the menstrual cycle begins with ovulation and ends when menstruation begins. The luteal phase is characterized by a gradual rise in the steroid hormone progesterone.
Luteinization (luteinisation) is the set of processes by which differentiation of the thecal and granulosa cells of the post-ovulatory ovarian follicle, results in formation of a corpus luteum.
Luteinizing hormone (LH) is a hormone released by the pituitary glands that regulates a female’s menstrual cycle and ovulation. LH also plays an important role in a male’s sperm production, as it stimulates the production of male sex hormones.