Fallopian Tubes

What springs to mind when Fallopian tubes are mentioned?  That they “connect” the ovaries to the uterus which leads finally to the vagina and the outside of the body?  Perhaps you think about ectopic pregnancies, as most ectopic pregnancies are indeed “tubal” pregnancies.  Whatever you may think of when Fallopian tubes are brought up, they are some of the least considered and understood parts of a woman’s reproductive tract.  Besides connecting the uterus and ovaries, do they do anything else?  Are they homologous to any part of the male anatomy?  Let’s try to answer some of the most common questions about Fallopian tubes.

First, where does the name “Fallopian” come from?  Unlike most parts of a woman’s reproductive system, this name does not come from Latin or Greek.  The Fallopian tubes are named for Gabriele Falloppio, a 16th-century Italian anatomist.  The canal through which the facial nerve runs after leaving the auditory cochlear nerve is also named after him–the aquaeductus Fallopii.

Back to the subject, why are the Fallopian tubes so often ignored?  Perhaps it has something to do with the lack of pathology or disease associated with the Fallopian tubes.  The most common maladies associated with the Fallopian tubes are, indeed, tubal (ectopic) pregnancy and pelvic inflammatory disease (PID).  (To read about two cases of rare ectopic pregnancies, click here.)  Ectopic  pregnancies are estimated to account for less than two of every one-hundred pregnancies.  PID is estimated to occur in nearly one in seven women in the United States.  PID accounts for a large number of all ectopic pregnancies, especially tubal.  Other disease are very rare in the Fallopian tubes.  Cancer, for example, is extremely rare and when it occurs it is often the result of adjacent cancer (such as ovarian).

So, what does a Fallopian tube look like?

The above sketch shows the different parts of the Fallopian tubes.  The fimbriae are the fringe-like extensions from the ostium of the Fallopian tube.   During ovulation, hormones stimulate the fimbriae to make a gentle sweeping motion against the ovaries to pull the released egg (or ovum) into the Fallopian tube.  The ovary and Fallopian are not actually connected to each other.  The ostium is where the fimbriae end and the Fallopian tube begins.  The infundibulum is the wider end of the Fallopian tube that narrows into the ampulla, which is the twisting portion of the tube in the above sketch.  It is where most fertilizations occur.  The ampulla continues into the isthmus, the shortest and most narrow portion of the Fallopian tube.  The pars uterina is the place where the uterus and Fallopian tube connects.

This sketch indicates better how the Fallopian tubes, uterus, and ovaries are all connected (or, in fact, not connected).  Most human Fallopian tubes are between seven and fourteen centimeters in length. Once an egg has entered the Fallopian tube, the mucosal cilia of the Fallopian tube move the egg towards the uterus.  The cilia are finger-like projects that sweep or push.  (Cilia are also found in the windpipe and sweep mucus and dust away from the lungs.)  Finally, Fallopian tubes are not homologous to any structure in the male body, thus they are completely unique to the female body.  (The ovaries, for example, are homologous to testes in males.)

Now, hopefully you and I both know a little more about the Fallopian tubes.  Want to know more or already know more and want to share it?  Please, don’t be shy!

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Rare Ectopic Pregnancy

Last night The Learning Channel replayed a program that I originally saw about a year ago entitled “Extraordinary Pregnancies.” It told the story of two women and their ‘extraordinary pregnancies’: Zahra in Morocco and Jane in England. The program is the repackaging of two other British programs that aired several years ago. Both women experienced rare complications from ectopic pregnancies. Each case is fascinating, to me at least, so let’s explore their cases a little more in depth–Zahra here, Jane in the next entry.

Zahra Aboutalib, a woman from just outside Casablanca, became pregnant at twenty-six years old and early in her pregnancy experienced excruciating abdominal pain. The pain eventually went away and in 1955 she went into labor. After laboring for more than two days, her family decided to take her to the closest hospital. In the hospital she saw other women undergo cesarean section and die because of the poor conditions in the hospital. Doctors told her she must have a c-section, too, and she decided she did not want to die too. She left the hospital still in pain and went home. Eventually the pain ceased and she remained pregnant. In Moroccan culture, there is a belief that babies can “sleep” inside of their mothers for indefinite periods of time. Assuming she had a sleeping baby, Zahra continued her life and adopted three children remaining pregnant for 46 years until terrible pain returned in her early 70s. Her children finally insisted she see a doctor. Doctors examined her and believed she had an ovarian tumor. After several rounds of testing and imaging, the doctors realized she was still carrying the child she conceived nearly five decades before.

When Zahra had become pregnant years before she had had an ectopic pregnancy in the fallopian tube. An ectopic pregnancy is any implantation of a fertilized egg outside of the uterus. As the fetus grew the fallopian tube expanded and finally burst, cause the pain early in her pregnancy. This occurrence can be quite dangerous for the mother and very often results in the death of the fetus. Amazingly, Zahra’s fetus continued to grow and attached itself through its placenta to Zahra’s internal organs. Because her fetus was outside of the uterus she could not vaginally deliver the child when she went into labor. C-section would have been the only way to extricate the child, though because of the dangerous circumstances she and her child may have perished. When the pain of labor subsided it was because her child has died inside of her. Her body could not absorb the child and, recognizing it as a foreign object, began to calcify the child resulting in what is called a lithopedion (stone child).

When the doctors decided to operate they faced a difficult challenge. The calcification of the baby Zahra bore had attached itself to many of her internal organs and her peritoneum (the lining of the abdominal cavity). The surgery was dangerous, but after hours of delicate maneuvering the surgeons were able to remove the whole, calcified child from Zahra’s stomach. The medical team dissected the lithopedion to study just how the calcification process works in cases like this. Zahra’s is one of the oldest lithopedions ever recorded. Zahra recovered fully from the procedure and returned to normal life.

Lithopedions are rare and are an extremely interesting occurrence. As the world moves towards a more Western model of medicine it is less likely that lithopedions will develop as most ectopic pregnancies can be surgically treated with less of a risk of to the mother and child. However, when other complications arise, that may change as we will see with the case of Jane in the next entry. Stay tuned! Comments, question? I’d love to hear from you.