Essentially, ectopic pregnancies occur as a result of the developing embryo (earliest form of development of a baby) implanting in the fallopian tube (97%) or anywhere else outside the endometrial lining of the uterus. Most ectopic pregnancies (not all) are tubal ectopics and hence ectopic pregnancies are often referred to as tubal pregnancies. While a direct cause may not be easily identified in most cases of tubal pregnancies, generally anything that allow the sperm to swim through the tube to fertilize the oocyte (ovum or egg) in the ampullary portion (portion of the tube where fertilization naturally occurs) of the fallopian tube but prevents the ensuing zygote (embryo or fetus, also the earliest form of in the development of a baby) from passing back from the tube to the uterus will result in a tubal ectopic pregnancy. However, below are risk factors for the occurence of tubal pregnancies.
1) Previous infections of the tube resulting in scaring of the tubes and or damage to the cilliary mechanisms ( important in creating a current that sweeps the formed zygote from the tube to the uterus/womb) of the fallopian tube most commonly following PID (pelvic inflammatory Disease) secondary to chlamydia and or gonorrhea infections.
2) Previous history of an ectopic pregnancy
3) Previous surgeries resulting in scarring around the fallopian tubes.
4) Previous history of a surgical termination of pregnancy
5) Changes in concentration of some hormones that may alter the motility of the fallopian tube and in very rare cases.
6) The presence of an abnormally long fallopian tube inherited by some women, due to exposure of such women to some drugs taken by their mother while still in their mother’s womb prior to their delivery. Luckily, such drugs are no more in use in modern days obstetrics.
While the commonest risk factors remain PID, other risk factors are
8) Advanced age of carrying pregnancy ( getting pregnant above 35 yrs slightly increases the odds of having an ectopic pregnancy)
9) Conception achieved by assisted reproductive techniques such as IVF and ET (invitro fertilization and embryo transfer).
10) Conception achieved after a failed female sterilization procedure or while on an Intra uterine contraceptive device for family planning.
Remember these are mere risk factors as many women with the above characteristics will not develop ectopic pregnancies and perhaps a combination of many factors may be required for one to develop an ectopic pregnancy. For more information, kindly CHAT WITH OUR CONSULTANTS.