Female genitalia

In fact, many female friends may not have a clear understanding of the female external genitalia. The external genitalia mainly include the clitoris, vulva, clitoral hood, labia minora, labia majora, etc. You also need to pay attention to the female external reproductive organs, because if you do not pay attention to their hygiene, it is easy to lead to the growth of bacteria and germs, and lead to the occurrence of gynecological diseases.

External genitalia

clitoris

The clitoris is an erectile structure, homologous to the male penis, located below and behind the anterior commissure of the labia majora. The clitoris contains two corpora cavernosa. The corpus cavernosum of the clitoris can be divided into three parts: the clitoral crus, the clitoral body and the clitoral glans. The clitoral crus is cylindrical, attached to the sciatic branch and the inferior pubic branch, and covered with the ischiocavernosus muscle. Near the lower edge of the pubic symphysis, the two sides of the clitoral crus are connected to form the clitoral body. There is an incomplete cavernous septum (also known as the pectinate septum) between the two clitoral bodies that separates them. The body of the clitoris turns forward and downward, and its free end is the glans clitoridis. The glans clitoridis is a small round nodule with a diameter of 6-8 mm and is surrounded by the clitoral hood. There is often smegma in the clitoral groove between the glans clitoridis and the clitoral hood. The glans clitoridis is connected to the labia minora by the frenulum. The outside of the clitoral sponge body is covered with a folded membrane, and the outside of the tunica albuginea is covered with the clitoral fascia. There are two connective tissue cords, one superficial and one deep, between the dorsal side of the clitoral body and the pubic symphysis. The superficial cord is the clitoral ligament, and the deep cord is called the suspensory ligament of the clitoris. The corpus cavernosum of the clitoris can also become engorged with blood and become erect. The glans clitoris is rich in nerve endings and is highly sensitive, making it easily stimulated to cause an erection, making it an important structure for sexual response.

Vulva refers to the external female genitalia

The mons pubis is the soft, fleshy tissue beneath the pubic hair that protects the female internal reproductive organs.

The clitoral hood protects the clitoris and is formed by the upper junction of the two labia minora.

The labia majora are soft and thick skin tissue that contains oil-producing glands and a small amount of pubic hair. They are a pair of oblong raised skin folds on both sides of the vulva, close to the inner sides of the thighs. It is connected to the mons pubis in front and the perineum in the back; it stretches downward and backward from the mons pubis. The left and right labia majora in front unite to form the anterior commissure, and the two ends in the back join to form the posterior commissure. The posterior commissure is located in front of the anus, but is not as obvious as the anterior commissure. There is pubic hair outside the labia majora. Subcutaneous tissue contains adipose tissue, elastic fibers and venous plexus, and hematoma occurs after injury. The labia majora of unmarried women close naturally, covering the vaginal opening and urethral opening. The labia majora of multiparous women spread apart due to the impact of childbirth.

The labia minora are a pair of soft, mucous membrane wrinkles of skin located on the inside of the labia majora, with a moist surface. The upper ends of the left and right sides of the labia minora are forked and connected to each other. The skin fold above is called the clitoral hood, and the skin fold below is called the clitoral frenulum. The clitoris is located in the middle of them. The lower ends of the labia minora meet at the bottom of the vaginal opening, called the frenulum. There are abundant nerves under the labia minora mucosa, so the sensitivity is keen.

The zero-shaped area surrounded by the labia minora on both sides of the vestibule is called the vestibule. The surface is covered with mucous membrane and is approximately a triangle. The tip of the triangle is the clitoris, the base is the frenulum of the labia, and the two sides are the labia minora. The urethra opens in the upper part of the vestibule. The vaginal opening is at its lower part. Also located in this area are the paraurethral glands, vestibular bulbs, and greater Bartholin's glands.

Vestibular bulbs The vestibular bulbs are a pair of spongy tissues, also known as the bulbospongiosity, which have erectile properties. Located on both sides of the vaginal opening. It is connected to the clitoral vein in front and the Bartholin's gland in the back, and its surface is covered by the bulbospongiosus muscle. Bleeding easily after injury.

Bartholin's gland Bartholin's gland is also called Bartholin's gland. Located at the lower end of the vagina, behind the labia majora, it is also covered by the bulbospongiosus muscle. It is a gland on each side, the size of a small bean. Its glandular duct is very narrow, about 1.5-2 cm, opening on the inner side of the lower end of the labia minora. Most of the epidermis of the glandular duct is squamous epithelium, and only the innermost end of the duct is composed of a layer of columnar cells. When sexually excited, the gland secretes yellow-white mucus, which lubricates the vaginal opening. This gland cannot be felt during a normal examination.

The urethral opening is an irregular oval hole between the lower edge of the pubic symphysis and the vaginal opening, through which urine flows out. There is a pair of glands on the posterior wall, called paraurethral glands, which open on the posterior wall of the urethra and are often where bacteria lurk.

The vaginal opening is the exit of the vagina to the outside. It is the place where menstrual blood and vaginal secretions are discharged, and it is also the place where the fetal head is exposed during delivery.

The vaginal opening is covered by an incompletely closed mucous membrane called the hymen. There is a hole in the middle of the hymen through which menstrual blood flows out. The size of the hymen hole and the thickness of the membrane vary from person to person. After the hymen is broken, the mucous membrane appears as many small round balls, which become the hymen scar.

The perineum is the thin membrane between the vaginal opening and the anus. During childbirth, a very large extension will occur, allowing the fetal head to smoothly emerge from the vaginal opening.

Internal genitalia

The vagina should be accurately called the reproductive tract, because it is the place where the penis is held during sexual intercourse and the place where semen is received; it is the place where the main sexual excitement is experienced during sexual life and it is also the channel for the delivery of the fetus. Under normal conditions, it is about 8-10cm long and the width is a closed potential cavity. During sexual excitement, it changes greatly and can provide a large variable space. This is because the vaginal wall is composed of three layers of tissue: the surface layer is mucous membrane, the middle layer is muscle, and the outer layer is elastic fiber tissue. There are a large number of wrinkles in the vagina, which are extremely extensible and elastic. Its upper end is wider than the lower end, the lower end opens to the vagina, and the upper end contains the cervix. It is usually like a deflated balloon with the four walls close together. When sexually excited, the inner 2/3 can expand, commonly known as "internal erection", and the outer 1/3 is clenched, also called the "orgasm platform". Its elasticity and expansion force make the combination of the penis and the vagina reach the most beautiful degree of compatibility, which is conducive to the enjoyment of sex and the injection, temporary storage of semen and the swimming of sperm into the uterine cavity. Of course, if you want to have children, you must also complete the reproductive function. During sexual excitement, the vaginal wall may secrete fluid due to the expansion of the surrounding venous plexus to lubricate the vagina, facilitating the insertion and thrusting of the penis. However, the elasticity, wrinkles and exudate of the vaginal wall are regulated by endocrine, especially estrogen. The vaginal epithelium of young girls and postmenopausal women is thin, with few wrinkles, poor elasticity, weak self-cleaning and wetting effects, and is easily traumatized and infected. The contraction of the sphincter and uterine muscles around the vagina during orgasm can be objectively recorded, but the various accompanying experiences cannot be reflected. It can be considered that orgasm and sexual experience are a comprehensive feeling or functional manifestation of physical physiology and brain psychology, especially in women.

Uterus The uterus is located in the pelvic cavity and is in the shape of an inverted pear. The surrounding ligaments fix it in the pelvic cavity. The uterus is divided into three parts: the body, the fundus and the cervix. From puberty to menopause, the regulation of female hormones in a woman's endometrium undergoes cyclical changes, making it receptive to the implantation of a fertilized egg at a certain time of each month. The uterus is the place where the fetus is nurtured. The fertilized egg implants here and gradually grows and develops into a mature fetus. After full term, the uterus contracts and delivers the fetus. The capacity of the uterus does not exceed 10 ml when there is no pregnancy, and can reach 4000 ml at full-term pregnancy; the weight of the uterus also increases from about 50 grams to about 1000 grams to meet the needs of nurturing the fetus. From puberty to menopause, if women do not become pregnant, the endometrium will undergo cyclical changes and exfoliation under the action of ovarian hormones, resulting in menstruation.

The fallopian tube is a thin tube about 10 to 13 cm long that has the function of transporting sperm and eggs, and is also the place where sperm and eggs meet for fertilization. After the mature egg is released from the ovary, it is transported into the fallopian tube from the abdominal cavity through the fimbria of the fallopian tube. The fallopian tubes are located on both sides of the uterus, and the mucous membrane of their inner walls is completely covered with vibrating cilia. After the egg enters the fallopian tube, it gradually moves toward the uterus with the help of the peristalsis of the fallopian tube and the movement of cilia. At this time, if it encounters sperm, it will combine to become a fertilized egg, which will continue to divide and develop while moving toward the uterus, and then enter the uterine cavity and implant. If the egg is not fertilized, it will die on its own after entering the uterine cavity.

Ovaries The ovaries are the female gonadal organs that contain many follicles. The ovaries are located on both sides of the uterus, behind and below the fallopian tubes, one on each side. The ovaries are oval in shape and are fixed in the pelvic cavity by ligaments. The ovaries discharge eggs and secrete female hormones. Female hormones maintain women's secondary sexual characteristics, such as breast bulge, subcutaneous fat accumulation, and shrill voice; they also maintain women's sexual function, and they act on the whole body through blood circulation. From puberty to menopause, that is, from around 13 to 49 years old, women release a mature egg every month. After menopause, the ovaries gradually atrophy.

Endometrium The endometrium refers to the layer that makes up the inner lining of the mammalian uterus. It responds to both estrogen and progesterone, and therefore can change significantly with the sexual cycle (estrus cycle, menstrual cycle).

Cervix The cervix is ​​located in the lower part of the uterus. It is approximately cone-shaped, 2.5-3 cm long, with the upper end connected to the uterine body and the lower end deep into the vagina. The vault at the top of the vagina divides the cervix into two parts: the part of the cervix that protrudes into the vagina is called the cervicovaginal part, and the part above the vaginal vault is called the upper cervicovaginal part.

The external os of the cervix The center of the cervix is ​​a long, fusiform tubular cavity that is slightly flattened front to back. Its upper end is connected to the uterine cavity through the internal os of the cervix, and its lower end opens to the vagina through the external os of the cervix. The cervical canal is between the internal and external openings. The external cervical os is round in nulliparous women and transversely fissured in women who have given birth through vaginal delivery.