OB Mod III terms Flashcards
Ampulla
The outer two-thirds of the fallopian tube; fertilization of the ovum by a spermatozoon usually occurs here.
Areola
Pigmented ring surrounding the nipple of the breast.
Broad ligament
A ligament that keeps the uterus centrally placed and provides stability within the pelvic cavity. It is a double layer that is continuous with the abdominal peritoneum. The broad ligament covers the uterus anteriorly and posteriorly and extends outward from the uterus to enfold the fallopian tubes.
Cardinal ligaments
1The chief uterine supports, the cardinal ligaments suspend the uterus from the side walls of the true pelvis. Also known as Mackenrodt’s or transverse cerical ligaments, they arise from the sides of the pelvic walls and attach the cervix in the upper vagina. They prevent uterine prolapse and support the upper vagina.
Cervix
The “neck” between the external os and the body of the uterus. The lower end of the cervix extends into the vagina.
Conjugate vera
The true conjugate, which extends from the middle of the sacral promontory to the middle of the pubic crest.
Cornua
The elongated portion of the uterus where the fallopian tubes enter.
Corpus
The upper two-thirds of the uterus.
Diagonal conjugate
An ateroposterior diameter that extends from the subpubic angle to the middle of the sacral promontory and is typically 12.5 cm. One of the three diameters that are used to assess the size and shape of the pelvic inlet.
Endometrium
The mucous membrane that lines the inner surface of the uterus.
Estrogens
The hormones estradiol and estrone, produced by the ovary.
Fallopian tubes
Tubes that extend from the lateral angle of the uterus and terminate near the ovary; they serve as a passageway for the ovum from the ovary to the uterus and for the spermatozoa from the uterus toward the ovary. Also called oviducts and uterine tubes.
False pelvis
The portion above the pelvic brim, or linea terminalis, that serves to support the weight of the enlarged pregnant uterus and direct the presenting fetal part into the true pelvis below.
Female reproductive cycle (FRC)
The monthly rhythmic changes in sexually mature women.
Fimbria
The funnel-like structure at the abdominal opening of the uterine tube that has many fingerlike projections (fimbriae) reaching out to the ovary.
Follicle-stimulating hormone (FSH)
Hormone produced by the anterior pituitary during the first half of the menstrual cycle, stimulating development of the graafian follicle.
Fundus
The upper portion of the uterus between the fallopian tubes.
Gonadotropin-releasing hormone (GnRH)
A hormone secreted by the hypothalamus that stimulates the anterior pituitary to secrete FSH and LH.
Graafian follicle
The ovarian cyst containing the ripe ovum; it secretes estrogens.
Human chorionic gonadotropin (hCG)
A hormone produced by the chorionic villi and found in the urine of pregnant women. Also called prolan.
Infundibulopelvic ligament
The ligament that suspends and supports the ovaries. It arises from the outer third of the broad ligament and contains the ovarian vessels and nerves.
Ischial spines
Prominences that arise near the junction of the ilium and ischium and jut into the pelvic cavity; used as a reference point during labor to evaluate the descent of the fetal head into the birth canal.
Isthmus
The straight, narrow part of the fallopian tube with a thick muscular wall and an opening (lumen) 2 to 3 mm in diameter; the sight of tubal ligation. Also, a constriction in the uterus that is located above the cervix and below the corpus.
Luteinizing hormone (LH)
Anterior pituitary hormone responsible for stimulating ovulation and for development of the corpus luteum.
Myometrium
Uterine muscular structure.
Nidation
Implantation of a fertilized ovum in the endometrium.
Obstetric conjugate
Distance from the middle of the sacral promontory to an area approximately 1 cm below the pubic crest.
Ovarian ligaments
Ligaments that anchor the lower pole of the ovary to the cornua of the uterus. They are surrounded by muscle fibers that allow the ligaments to contract.
Ovulation
Normal process of discharging a mature ovum from an ovary approximately 14 days prior to the onset of menses.
Pelvic cavity
The lower portion of the abdominopelvic cavity that contains the urinary bladder, the rectum, and internal parts of the reproductive system. The pelvic cavity is divided into the false pelvis and the true pelvis.
Pelvic diaphragm
Part of the pelvic floor composed of deep fascia and the levator ani and the coccygeal muscles.
Pelvic inlet
Upper border of the true pelvis.
Pelvic outlet
Lower border of the true pelvis.
Perimetrium
1The outermost layer of the corpus of the uterus. Also known as the serosal layer.
Progesterone
A hormone produced by the corpus luteum, adrenal cortex, and placenta whose function is to stimulate proliferation of the endometrium to facilitate growth of the embryo.
Prostaglandins (PGs)
Complex lipid compounds synthesized by many cells in the body.
Pubis
Pertaining to the pubes or pubic area.
Round ligaments
Ligaments that arise from the sides of the uterus near the fallopian tube insertions. They extend outward between the folds of the broad ligament, passing through the inguinal ring and canals and eventually fusing with the connective tissue of the labia majora.
Sacral promontory
A projection into the pelvic cavity on the anterior upper portion of the sacrum; serves as an obstetric guide in determining pelvic measurements.
Testosterone
The male hormone; responsible for the development of secondary male characteristics.
Transverse diameter
The largest diameter of the pelvic inlet; helps determine the shape of the inlet.
True pelvis
The portion that lies below the linea terminalis, made up of the inlet, cavity, and outlet.
Uterosacral ligaments
Ligaments that provide support for the uterus and cervix at the level of the ischial spines. They arise on each side of the pelvis from the posterior wall of the uterus and sweep back around the rectum to insert on the sides of the first and second sacral vertebrae.
Uterus
The hollow muscular organ in which the fertilized ovum is implanted and in which the developing fetus is nourished until birth.
Vagina
The musculomembranous tube or passageway located between the external genitals and the uterus of a woman.
Acrosomal reaction
Breakdown of hyaluronic acid in the corona radiate by enzymes from the heads of sperm; allows one spermatozoon to penetrate the ovum zona pellucida.
Amnion
The inner of the two membranes that form the sac containing the fetus and the amniotic fluid.
Amniotic fluid
The liquid surrounding the fetus in utero. It absorbs shocks, permits fetal movement, and prevents heat loss.
Bag of waters (BOW)
The membrane containing the amniotic fluid and the fetus.
Blastocyst
The inner solid mass of cells within the morula.
Capacitation
Removal of the plasma membrane overlying the spermatozoa’s acrosomal area with the loss of seminal plasma proteins and the glycoprotein coat. If the glycoprotein coat is not removed, the sperm will not be able to penetrate the ovum.
Chorion
The fetal membrane closest to the intrauterine wall that gives rise to the placenta and continues as the outer membrane surrounding the amnion.
Cleavage
Rapid mitotic division of the zygote; cells produced are called blastomeres.
Cotyledons
One of the rounded portions into which the placenta’s uterine surface is divided, consisting of a mass of villi, fetal vessels, and an intervillous space.
Decidua basalis
The part of the decidua that unites with the chorion to form the placenta. It is shed in lochial discharge after childbirth.
Decidua capsularis
The part of the decidua surrounding the chorionic sac.
Decidua vera (parietalis)
Nonplacental decidua lining the uterus.
Diploid number of chromosomes
Containing a set of maternal and a set of paternal chromosomes; in humans, the diploid number of chromosomes is 46.
Ductus arteriosus
A communication channel between the main pulmonary artery and the aorta of the fetus. It is obliterated after birth by rising PO2 and changes in intravascular pressure in the presence of normal pulmonary functioning. It normally becomes a ligament after birth but sometimes remains patent (patent ductus arteriosus, a treatable condition).
Ductus venosus
A fetal blood vessel that carries oxygenated blood between the umbilical vein and the inferior vena cava, bypassing the liver, it becomes a ligament after birth.
Ectoderm
Outer layer of cells in the developing embryo that gives rise to the skin, nails, and hair.
Embryo
The early stage of development of the young of any organism. In humans the embryonic period is from about 2 to 8 weeks’ gestation and is characterized by cellular differentiation and predominantly hyperplastic growth.
Embryonic membranes
The amnion and chorion.
Endoderm
The inner layer of cells in the developing embryo that gives rise to internal organs such as the intestines.
Fertilization
Impregnation of an ovum by a spermatozoon; conception.
Fetus
The child in utero from about the seventh to ninth week of gestation until birth.
Foramen ovale
Special opening between the atria of the fetal heart. Normally, the opening closes shortly after birth; if it remains open, it can be repaired surgically.
Gametes
Female or male germ cell; contains a haploid number of chromosomes.
Gametogenesis
The process by which germ cells are produced.
Haploid number of chromosomes
Half the diploid number of chromosomes. In humans there are 23 chromosomes, the haploid number, in each germ cell.
Lanugo
Fine, downy hair found on all body parts of the fetus, with the exception of the palms of the hands and the soles of the feet, after 20 weeks’ gestation.
Meiosis
The process of cell division that occurs in the maturation of sperm and ova that decreases their number of chromosomes by one-half.
Mesoderm
The intermediate layer of germ cells in the embryo that gives rise to connective tissue, bone marrow, muscles, blood, lymphoid tissue, and epithelial tissue.
Mitosis
Process of cell division whereby both daughter cells have the same number an pattern of chromosomes as the original cell.
Morula
Developmental stage of the fertilized ovum in which there is a solid mass of cells.
Placenta
Specialized disk-shaped organ that connects the fetus to the uterine wall for gas and nutrient exchange. Also called afterbirth.