What are the underlying causes of extra-uterine pregnancy?
Extra-uterine pregnancy may occur in any woman, even if there are no known underlying causes, but in general, some women are more at risk than others. One of the common causes of the underlying cause is any surgery or condition that affects the fallopian tubes, such as:
- Surgery of the fallopian tubes is done to correct a problem or open the tubes (which has been used to prevent tubal occlusion). If you have undergone another abdominal or pelvic surgery, the probability of an extra-uterus pregnancy will be slightly higher. In rare cases, when the woman is pregnant after having closed the tubes, the probability of extra-uterine pregnancy is 25% to 50%.
- Pregnancy out of the womb in the past. After a pregnancy outside the womb, the probability of another pregnancy outside the womb is about one to ten. If you have two or more pregnancies outside of the womb, it's likely that your other pregnancy is out of the womb at least one to four.
- There is an infection in the upper reproductive system (called pelvic inflammatory disease or PID). Pelvic inflammation is often caused by untreated sexually transmitted infections such as gonorrhea or chlamydia. Sometimes there is no symptom, so getting any of these sexually transmitted diseases increases the likelihood of an extra-uterus pregnancy, even if you do not think you have a pelvic inflammatory disease.
- Fertility problems. Infertility is often due to tubal damage, and if you become pregnant during infertility treatment, the probability of an extra-uterus pregnancy is higher than you are.
- If your mother has taken Diethyl Acetyl Dextrin (DES) during pregnancy, it may cause problems like abnormalities in the fallopian tube and uterus, which may increase your risk of uterine pregnancy (note that diethyl acetate Bastron has left the US in 1971 but is still available in some other countries). Ask your mother if he has taken this medicine during pregnancy.
A condition called endometriosis may cause a wound that affects the fallopian tubes and increases the likelihood of an extra-uterine pregnancy.
Women aged 35 or over are at an increased risk of developing extra-pregnancy when they are pregnant. This may be due to changes in the functioning of the tubes as they grow older, or that pelvic inflammatory disease may have been damaged by fallopian tubes in women who have had infections or periods of repeated pelvic inflammation.
- In rare cases, when you get pregnant while you have an IUD (an intrauterine device), the probability that this pregnancy is extra-uterine is more than average. IUD does not make pregnancy out of the uterus, it is only more effective in preventing oocyte placement in the uterus relative to it (because it prevents pregnancy in the womb and is more likely to be extra-uterine if pregnant). Of course, with the use of IUD, the overall probability of an extra-uterine pregnancy will be much lower in others, and the use of IUD in the past does not increase the likelihood of pregnancy outside the womb.
- If you smoke, your risk of extra-uterine pregnancy increases. One theory is that smoking may malfunction the normal functioning of the fallopian tubes. Some studies show that while using progestin-only hormone contraceptives, if pregnancy occurs, it's likely to increase beyond the uterus.