Chapter 12- Female Reproductive System: Anatomy & Physiology

external genitalia (genitals) (vulva)

-sex, or reproductive, organs visible on the outside of the body

-in females, it includes the labia minora, labia majora, clitoris, Bartholin glands, and mons pubis

gestation (pregnancy)

-length of time from conception to birth

-it usually extend approximately 280 days from the last menstrual period

-if it is less than 36 weeks, it is considered premature

lactation

production and release of milk by mammary glands

orifice

mouth; entrance, or outlet of any anatomical structure

internal female reproductive organs

includes the ovaries, fallopian tubes, uterus, and vagina

mons pubis

an elevation of adipose tissue covered by skin and coarse pubic hair that cushions the pubis (pubic bone)

perinuem

-the area between the vaginal orifice and the anus

-during childbirth, this may be surgically incised (episiotomy) to enlarge the vaginal opening for delivery

ova

female reproductive cells

female reproductive organs

designed to produce ova, transport the cells to the site of fertilization, provide a favorable environment for a developing fetus through pregnancy and childbirth, and produce female sex hormones

female sex hormones

-hormones responsible for the development of secondary sex characteristics, such as breast development and regulation of the menstrual cycle

-play an important role in the reproductive process, providing their influence at critical times during preconception, fertilization, and gestation

ovaries

-almond-shaped glands located in the pelvic cavity, one on each side of the uterus

-each of them contains thousands of tiny graafian follicles

graafian follicles

-tiny, saclike structures located in each ovary

-each contains an ovum

ovulation

the process when an ovum ripens, the mature follicle moves to the surface of the ovary, ruptures, and releases the ovum

corpus luteum

-small yellow mass that secretes estrogen and progesterone

-after ovulation, the empty follicle is transformed into it

-degenerates at the end of a nonfertile cycle

estrogen and progesterone

-secreted by corpus luteum

-influence the menstrual cycle and menopause

-prepare the uterus for implantation of the fertilized egg, help maintain pregnancy, promote growth of the placenta, and play an important role in development of secondary sex characteristics

fallopian tubes (oviducts) (uterine tubes)

-two extend laterally from superior angles of the uterus

-fimbriae project from them

fimbriae

fingerlike projections that create wavelike currents in fluid surrounding the ovary to move the ovum into the uterine tube

conception (fertilization)

-if the egg unites with a spermatozoon, the male reproductive cell, this takes place

-this egg then continues its journey to the uterus where it implants on the uterine wall

-if it does not occur, the ovum disintegrates within 48 hours and is discharged through the vagina

uterus

-contains and nourishes the embryo from the time the fertilized egg is implanted until the fetus is born

-muscular, hollow, inverted-pear-shaped structure

-located in the pelvic area between the bladder and rectum

-normally in a position of anteflexion

-consists of 3 parts: fundus, body, and cervix

anteflexion

the position of being bent forward

fundus

the upper, rounded part of the uterus

body

the central part of the uterus

cervix (neck of the uterus) (cervix uteri)

the inferior constricted portion of the uterus that opens into the vagina

vagina

-muscular tube that extends from the cervix to the exterior of the body

-its lining consists of folds of mucous membrane that give the organ an elastic quality

-includes the vaginal orifice, Bartholin glands, and clitoris

-serves as the organ of sexual intercourse and receptor of semen, discharges menstrual flow, and acts as a passageway for the delivery of the fetus

vaginal orifice

during sexual excitement, it is lubricated by secretions from the Bartholin glands

clitoris

-part of the vagina located anterior to the vaginal orifice

-composed of erectile tissue that is richly innervated with sensory endings

-similar in structure to the penis in the male, but is smaller and has no urethra

mammary glands (breasts)

-present in both sexes, but only function in females

-not directly involved in reproduction but become important after delivery

-their biological role is to secrete milk for the nourishment of the new born, called lactation

-begin to develop during puberty as a result of periodic stimulation of the ovarian hormones estrogen and progesterone

-fully developed by age 16

-each one is composed of 15 to 20 lobules of milk-producing glands that are drained by a lactiferous duct

-during pregnancy, they enlarge and remain so until lactation ceases

-at menopause, breast tissue begins to atrophy

estrogen

hormone responsible for the development of adipose tissue

adipose tissue

fat tissue which enlarges the size of the breasts until they reach full maturity

breast size

primarily determined by the amount of fat around the glandular tissue but is not indicative of functional ability

lactiferous duct

-duct that acts as a drain for milk-producing glands

-opens on the tip of the raised nipple

areola

slightly darker skin that circles the nipple

menarche

the initial menstrual period, occurring at puberty at about age 12 and continuing approximately 40 years, except during pregnancy

menstrual cycle

-consists of a series of phase, during which the uterine endometrium changes as it responds to changing levels of ovarian hormones

-the duration of it is approximately 28 days

pregnancy (gestation)

-during this, the uterus changes its shape, size, and consistency; it increases greatly in size and muscle mass; houses the growing placenta, which nourishes the embryo-fetus; and expels the fetus after it

-to prepare for it and serve as the birth canal at the end of pregnancy, the vagina canal elongates as the uterus rises in the pelvis

-the mucosa thickens, secretions increase, and vascularity and elasticity of the cervix and vagina become more pronounced

-it averages at 9 months and is followed by parturition

-causes enlargement of the breasts, sometimes to the point of pain

-toward the end of it, the myometrium begins to contract weakly at irregular intervals and, at this time, the full-term fetus is usually positioned head down within the uterus

parturition

term for childbirth

embryo

up to the 3rd month of pregnancy, the product of conception is referred to as this

fetus

from the 3rd month to the time of birth, the unborn offspring is referred to as this

menstrual

-the 1st phase of the menstrual cycle, days 1 to 5

1) uterine endometrium sloughs off because of hormonal stimulation, a process accompanied by bleeding

2) the detached tissue and blood are discharged through the vagina as menstrual flow

ovulatory

-the 2nd phase of the menstrual cycle, days 6 to 14

1) when menstruation ceases, the endometrium begins to thicken as new tissue is rebuilt

2) as the estrogen level rises, several ova begin to mature in the graafian follicles, usually with only one ovum reaching full maturity

3) at about the 14th day of the cycle, the graafian follicle ruptures, releasing the egg, a process called ovulation

4) the egg then leaves the ovary and travels down the fallopian tube toward the uterus

postovulatory

-the 3rd phase of the menstrual cycle, days 15 to 28

1) the empty graafian follicle fills with a yellow material and is now called the corpus luteum

2) secretions of estrogen and progesterone by the corpus luteum stimulate the building of the endometrium in preparation for implantation of an embryo

3) if fertilization does not occur, the corpus luteum begins to degenerate as estrogen and progesterone levels decrease

4) with decreased hormone levels, the uterine lining begins to shed, the menstrual cycle starts over again, and the 1st day of menstruation begins

labor (childbirth)

-the physiological process by which the fetus is expelled from the uterus

-occurs in 3 stages: stage of dilation, stage of expulsion, and placental stage or afterbirth

stage of dilation

the 1st stage of labor, which begins with uterine contractions and terminates when there is complete dilation of the cervix (10cm)

stage of expulsion

the 2nd stage of labor, the time from complete cervical dilation to birth of the baby

placental stage (afterbirth)

the last stage of labor, which begins shortly after childbirth when the uterine contractions discharge the placenta from the uterus

menopause

-the cessation of ovarian activity and diminished hormone production that occurs at about age 50

-usually diagnosed if absence of menses (amenorrhea) has persisted for 1 year

-many women experience hot flashes and vaginal drying and thinning (vaginal atrophy) as estrogen levels fall

-hormone replacement therapy (HRT) has become more controversial, but is still used to treat vaginal atrophy and porous bones (osteoporosis)

change of life (climacteric)

the period in which symptoms of approaching menopause occur