They move to propel the ovulated egg from the ovary towards the uterus. They also help distribute tubal fluid throughout the tube. The cilia of the fallopian tubes are most numerous at the ovarian end. They also change throughout the menstrual cycle. The beating movement of the cilia increases near the time of ovulation. Interestingly, some women with a condition known as Kartagener's syndrome remain fertile even though their cilia movement is impaired.
In rare cases, an accessory fallopian tube can form during development, which can affect fertility. This extra tube generally has an end that is near the ovary but does not extend into the uterus. Therefore, if an egg is picked up by the accessory fallopian tube, it can not be fertilized and implanted.
There is also a risk of an ectopic pregnancy in such an accessory tube, which can be dangerous. Other variations include extra openings, closed sacs, and functional changes to the fimbria. The primary function of the fallopian tubes is to transport eggs from the ovary to the uterus. The eggs are picked up by the fimbriae and then swept towards the uterus. This movement is directed both by the beating of the cilia and by peristalsis , which is rhythmic contractions of the muscles of the tubes.
When fertilization occurs, it is generally in the fallopian tubes. The sperm travel out from the uterus into the tubes, where they may encounter and fertilize an egg.
The fertilized egg then continues its movement towards the uterus. If a fertilized egg implants in the uterus, and continues to develop, it becomes a uterine pregnancy. Successful transport of eggs through the fallopian tubes is necessary for someone to get pregnant without medical intervention.
This is why tubal sterilization , which interrupts the function of the tubes, is an effective form of permanent contraception. This is sometimes referred to as getting one's "tubes tied. Ectopic pregnancy is the condition most commonly associated with the fallopian tubes. It occurs when there is a delay in the transport of the fertilized egg towards the uterus. In such cases, the fertilized egg may implant and cause an ectopic pregnancy inside the tube. An ectopic pregnancy cannot be safely carried to term.
It may be treated expectantly, medically, or surgically. Without treatment, ectopic pregnancy can be fatal. It is the second leading cause of pregnancy-related death in the United States. Salpingitis refers to an inflammatory disease that leads to the thickening of the tubes.
There are two types of salpingitis. Salpingitis isthmica nodosa involves formation of nodules inside the isthmus section of the tubes. These nodules make it more difficult for eggs to pass through the tubes and increase the risk of ectopic pregnancy. They also reduce fertility. In contrast, non-nodular salpingitis just called salpingitis is usually caused by an infection, such as those associated with pelvic inflammatory disease. Either acute or chronic salpingitis can also cause tubal blockages and scarring, but not the characteristic nodules of salpingitis isthmica nodosa.
Tubal infertility is a generic term that describes when someone is unable to conceive a pregnancy due to issues with their fallopian tubes. It may be due to a number of causes, from congenital abnormalities to infectious complications. One of the most common causes of tubal factor infertility is complications of chlamydia. Tubal factor infertility is responsible for a large portion of cases of female infertility.
Tubal torsion, or adnexal torsion, occurs when the fallopian tube gets twisted, possibly affecting its blood supply. Although this usually happens alongside ovarian torsion, it can happen on its own. Left untreated, tubal torsion can affect fertility.
Hydrosalpinx describes when one or both fallopian tubes become swollen and filled with fluid. This can be the result of an infection. It can also be caused by an obstruction of one or both ends of the fallopian tube. Primary cancer of the fallopian tube is very rare, but can happen.
Less than 1 percent of gynecologic cancers are thought to originate in the fallopian tubes. Fallopian tube metastases can also occur from non-gynecologic cancers. A hysterosalpingogram is a special type of X-ray used to examine the fallopian tubes. During this text, dye is injected through the cervix.
That dye flows through the uterus and into the fallopian tubes. Using injection and microradiographic and histologic techniques to study the vascular anatomy of the uterus, Farrer-Brown et al. In the broad ligament each uterine artery supplies lateral branches that immediately enter the uterus and give off tortuous anterior and posterior arcuate divisions, which run circumferentially in the myometrium approximately at the junction of its outer and middle thirds.
In the midline the terminal branches of both arcuate arteries anastomose with those of the contralateral side. Each arcuate artery throughout its course gives off numerous branches running both centrifugally towards the serosa and centripetally towards the endometrium. The arteries to the serosa at first are directed radially and then frequently became more circumferential. There is a plexus of small arterial radicals with a radial distribution located immediately below the serosa. The inner two-thirds of the myometrium is supplied by tortuous radial branches of the arcuate arteries.
They provide numerous branches terminating in a capillary network which surrounds groups of muscle fibers. An abrupt change in the density of the arterial pattern occurs at the junction of the basal layer of the endometrium with the subjacent myometrium. The endometrial vessels are relatively sparse in comparison with those of the myometrium at all stages of the menstrual cycle. The uterus is partially supported by three pairs of ligaments.
The paired round ligaments extend from the anterosuperior surface of the uterus through the internal inguinal rings and through the inguinal canals to end in the labia majors. They are composed of muscle fibers, connective tissue, blood vessels, nerves, and lymphatics.
The round ligaments stretch with relative ease, particularly in pregnancy. The uterosacral ligaments are condensations of endopelvic fascia that arise from the posterior wall of the uterus at the level of the internal cervical os. They fan out in the retroperitoneal layer and attach broadly at the second, third, and fourth segments of the sacrum. They are predominately composed of smooth muscle but also contain connective tissue, blood vessels, lymphatics, and parasympathetic nerve fibers. The cardinal ligaments form the base of the broad ligament.
They are composed of perivascular connective tissue and nerves that surround the uterine artery and veins. The cardinal and uterosacral ligament complex is collectively called the parametrium. The broad ligament is formed by folds of peritoneum covering the fallopian tubes, the infundibulopelvic vessels, and the hilus of the ovary.
It contains a number of structures: fallopian tube, round ligament, ovarian ligament, uterine and ovarian blood vessels, nerves, lymphatics, and mesonephric remnants.
Below the infundibulopelvic structures, the anterior and posterior leaves of peritoneum lie in apposition, leaving a clear space below the tube with its tubal branch of the uterine artery. This avascular area is useful to the surgeon in isolating the adnexal structures and in avoiding blood vessels while performing tubal ligations. The endometrium lines the uterine cavity and is considered to have three layers: the pars basalis, the zona spongiosa, and the superficial zona compacta.
The straight branches of the radial arteries of the uterus terminate in capillaries in the basal layer, while the spiral or coiled branches penetrate to the surface epithelium, where they give rise to superficial capillaries. The endometrium varies greatly depending on the phase of the menstrual cycle. Proliferation of the endometrium occurs under the influence of estrogen; maturation occurs under the influence of progesterone.
The uterine endometrial cycle can be divided into three phases: the follicular or proliferative phase, the luteal or secretory phase, and the menstrual phase.
The follicular, or proliferative phase, spans from the end of the menstruation until ovulation. Increasing levels of estrogen induce proliferation of the functionalis from stem cells of the basalis, proliferation of endometrial glands, and proliferation of stromal connective tissue.
Endometrial glands are elongated with narrow lumens and their epithelial cells contain some glycogen. Glycogen, however, is not secreted during the follicular phase. Spiral arteries elongate and span the length of the endometrium. After formation of the corpus luteum, the endometrial glands grow, become tortuous, and secrete. The luteal, or secretory, phase begins at ovulation and lasts until the menstrual phase of the next cycle Fig.
At the beginning of the luteal phase, progesterone induces the endometrial glands to secrete glycogen, mucus, and other substances. These glands become tortuous and have large lumens due to increased secretory activity. The spiral arteries extend into the superficial layer of the endometrium.
The spiral capillaries develop a terminal network of superficial capillaries. These changes result in the formation of a predeciduum prepared for the arrival of the trophoblast.
Luteal phase endometrium. In the absence of fertilization by day 23 of the menstrual cycle, the corpus luteum begins to degenerate and ovarian hormone levels decrease. As estrogen and progesterone levels decrease, the endometrium undergoes involution. During days 25—26 of the menstrual cycle, endothelin and thromboxin begin to mediate vasoconstriction of the spiral arteries. The resulting ischemia may cause menstrual cramps. By day 28 of the menstrual cycle, intense vasoconstriction and subsequent ischemia cause mass apoptosis of the functionalis, with associated bleeding.
The menstrual phase begins as the spiral arteries rupture secondary to ischemia, releasing blood into the uterus, and the apoptosed endometrium is sloughed off Fig. During this period, the functionalis is completely shed.
Arterial and venous blood, remnants of endometrial stroma and glands, leukocytes, and red blood cells are all present in the menstrual flow. Menstrual phase endometrium. Data on the lymphatic vessels of the uterus have been coordinated by Reynolds. The lymphatic capillary bed is arranged in four zones: 1 the lower uterine segment with its rich supply of fine capillaries, 2 the subserosa of the corpus with a few lymphatics, 3 a deep subserosal network, and 4 a plentiful supply in the muscularis proper.
These vessels increase greatly in number and size during pregnancy. The collecting system of the uterine lymphatics is formed from anastomoses of a lateral-uterine descending network of lymph vessels which unites with collecting vessels from the utero-ovarian pedicle and the external iliac area. Lymphatic drainage of the uterus and upper two-thirds of the vagina is primarily to the obturator and internal and external iliac nodes.
The fallopian tubes are bilateral muscular structures of paramesonephric duct origin. They are from 7 to 12 cm in length and usually less than 1 cm in diameter. The tubes or oviducts have a lumen that varies considerably in diameter. It is extremely narrow, being less than 1 mm at its opening into the uterine cavity. It is wider in the isthmus Fig. The tube begins in the uterine cavity at the cornu and penetrates the myometrium intramural or interstitial portion.
The second portion is the relatively straight and narrow portion of the tube which emerges from the uterus posterior to and a little above the origin of the round ligament. The lumen of the narrow isthmus is relatively simple, with a few longitudinal folds. This portion of its tube is 2 or 3 cm long. There are three layers of musculature: the inner longitudinal, the middle circular layer, and the outer longitudinal layer. There is some evidence that the isthmus may act as a sphincter.
Photomicrograph showing the isthmic portion of the fallopian tube; it is in this portion of the tube that spasm may occur and close the lumen. The mucosa is lined by columnar epithelium which surrounds the lumen.
The columnar cells have cilia. The circular muscle layer is thickest at the isthmus and thinnest at the infundibulum. Photomicrograph low power of the ampullary portion of the fallopian tube. The mucosa forms folds which in transsection of the tube simulate glandular structures. There are, however, no true secreting glands in the oviduct. The ampulla is the largest and longest portion of the tube, approximately 5 cm or more in length.
The lumen enlarges from 1 or 2 mm near the isthmus to over a centimeter at the distal portion. The mucosa has multiple longitudinal folds. The ampulla is the portion usually involved in gonorrheal salpingitis and tubo-ovarian abscesses and is the site of most ectopic pregnancies.
At the distal end of the tube is the trumpet shaped infundibulum. The tube ends in a number of fimbriae or frond-like projections; the largest of these is ordinarily in contact with the ovary and is known as the ovarian fimbria. The peritoneal cavity in the female is connected with the exterior of the body through the patent distal end of the tube by way of the uterus and vagina.
This opening is of considerable clinical importance as blood, ascending infections, or pus can pass out of the tube to invade the abdominal cavity, with resultant pain, endometriosis, or pelvic infection. The epithelial lining of the tube has been studied extensively by light and electron microscopy. On light microscopic examination, four types of cells can be readily seen.
Secretory cells or nonciliated cells have a heavily granular cytoplasm and an oval nucleus. The ciliated cells have fine granular cytoplasms and are relatively square with large round nuclei.
Pauerstein 4 has reviewed and summarized the numerous studies on tubal ultrastructure. Two basic cell types have been described, ciliated and secretory. The ciliated cells have a clear cytoplasm with vesicular reticulum.
This flap is called the omentum. Below is a sample of the sources used in our ovarian cancer information. If you would like more information about the sources we use, please contact us at cancerinformationteam macmillan. Fotopoulou C, et al. European Journal of Obstetrics, gynecology, and reproductive biology. National Institute for Health and Care Excellence. Ovarian cancer: recognition and initial management.
Clinical guideline CG April Available from: www. Below is a sample of the sources used in our germ cell ovarian cancer information. Royal College of Obstetricians and Gynaecologists. Management of female malignant ovarian germ cell tumours.
Scientific impact paper no. Nov It has been reviewed by expert medical and health professionals and people living with cancer.
We try to make sure our information is as clear as possible. We use plain English, avoid jargon, explain any medical words, use illustrations to explain text, and make sure important points are highlighted clearly. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected. Our aims are for our information to be as clear and relevant as possible for everyone.
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