By Takatakatakumi - Own work, CC BY-SA 3.0, Wikimedia
Ectopic pregnancies are the leading cause of pregnancy-related deaths in the first trimester. Studies suggest that about 1 in 50 pregnancies in the U.S. are ectopic.
Normally in humans, fertilization occurs in the fallopian tube. Fertilization is the union of the egg and the sperm to form a zygote. After fertilization in the fallopian tube, the zygote now moves down to the uterus to implant in the uterine wall where normal growth and development of the zygote occurs.
Any alteration in this normal migration and implantation of the fertilized egg results in an ectopic pregnancy. Therefore, an ectopic pregnancy is the implantation of the fertilized egg (zygote) outside the normal endometrium of the uterus.
By Bonnie Urquhart Gruenberg - Own work, CC BY-SA 4.0, Wikimedia
The possible locations where this abnormal implantation can occur include the fallopian tube. This is the commonest site of ectopic pregnancy which occurs when the fertilized egg fails to migrate to the uterus and starts growing in the fallopian tube. Due to the narrow diameter of the fallopian tube, this leads to the rupture of the fallopian tube since it cannot expand to accommodate the growing zygote. This ruptured ectopic pregnancy is a medical emergency.
Other sites of ectopic pregnancy include the ovary, the abdomen, or even the cervix. Cervical ectopic pregnancy causes severe bleeding through the vagina and can be mistaken to be a miscarriage. But it's an ectopic pregnancy.
Regardless of where outside the uterus the zygote implants, an ectopic pregnancy is not a viable pregnancy: It cannot result in a healthy baby, and it needs to be ended to protect the health of the pregnant woman. That’s why they require prompt diagnosis and treatment
By Drvgaikwad, Dr. Vilas Gayakwad - Own work. CC BY-SA 3.0, Wikimedia
Now, let's look at the common causes/risk factors of ectopic pregnancy. The commonest cause is damage to the fallopian tube. Any form of damage to the fallopian tube can result in ectopic pregnancy. This damage can be from Pelvic Inflammatory Disease (PID), sepsis following an abortion, previous surgery on the fallopian tube, inflammation of the fallopian tube (salpingitis), etc.
Other risk factors include; Previous ectopic pregnancy, Intrauterine contraceptive devices (IUD), history of smoking, endometriosis, Sexually transmitted infections, etc. The use of Assisted Reproductive Technology (ART) like In vitro fertilization is also another risk factor for ectopic pregnancy.
How does ectopic pregnancy manifest?
An ectopic pregnancy can present quietly when it is not ruptured, but when it is ruptured, it's an emergency.
Most of the time, an ectopic pregnancy happens within the first few weeks of pregnancy. You might not even know that you're pregnant and may not notice any problems.
By Unknown photographer/artist - Public Domain, Wikimedia
Symptoms of ectopic pregnancy in some cases may just resemble the symptoms of early pregnancy. Clinical symptoms include; Abdominal pain, commonly in the lower part of the abdomen. It can be on one or both sides of the abdomen. There may be irregular vaginal bleeding and amenorrhoea (absence of monthly menstruation). When ruptured, the patient may have fainting spells, lightheadedness, or signs of shock.
To make a diagnosis of ectopic pregnancy, some of the necessary tests include; Serum hCG levels and a urine pregnancy test. An ultrasound scan will show that the uterus is empty and a gestational sac outside the uterus. The full blood count is also done to estimate the blood loss, especially in ruptured ectopic. And other tests.
How is Ectopic pregnancy treated?
For unruptured ectopic, medical treatment is commonly used. Methotrexate is the drug of choice used here. When the symptoms are mild, expectant management with regular monitoring of the Serum human Chorionic Gonadotrophin (hCG) level can be done. However, when the ectopic is ruptured, surgery is the preferred treatment option.
By Bobjgalindo - Own work, CC BY-SA 4.0, Wikimedia
Finally, Since there is no exact prevention for ectopic pregnancy, it is important to know the early signs and symptoms to ensure a prompt diagnosis and treatment before complications set in. It is important to avoid some of the modifiable risk factors like smoking, septic abortions, and Pelvic Inflammatory Diseases (I will talk more about Pelvic Inflammatory Disease in my next topic).
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