In ectopic pregnancy, ectopic means out of place. So an ectopic pregnancy means that a pregnancy happens somewhere other than in the uterine cavity. In order for an ectopic pregnancy to take place, a couple of things need to happen differently from the normal process of a pregnancy. First, following ovulation, the egg must be fertilized and come to rest somewhere other than the endometrium of the uterine cavity. Next, when it arrives at this destination, It must implant on a surface with a rich enough blood supply to support a developing embryo.
Ectopic pregnancies have been known to happen on various surfaces, including the ovaries, intestines, and most commonly in the ampulla of the fallopian tube. After implantation, the embryo starts developing and growing just like it would in a normal pregnancy. Over time, a few different things can happen. Sometimes the tissue can no longer provide a sufficient blood supply for the embryo.
leading to its death. On the other hand, if the tissue can supply the embryo with sufficient blood, then hormones from the corpus luteum and placenta can lead to a missed menstrual period and other body changes like nausea and fullness of breasts, which are typically seen in early pregnancy. If the ectopic pregnancy happens in the ampulla of the fallopian tube, it eventually runs out of space.
Slowly, the ectopic pregnancy stretches the nerve fibers within the wall of the fallopian tube. causing lower abdominal pain. Eventually, the expansion causes damage to the wall of the ampulla, potentially rupturing the fallopian tube. A ruptured ectopic pregnancy can lead to massive hemorrhaging into the abdominal cavity, and the blood can irritate the peritoneum which can cause referred pain to the shoulder. Occasionally, there might be light vaginal bleeding as well.
The combination of internal bleeding, severe pain, and damage to the fallopian tube make an ectopic pregnancy a medical emergency. The cause of an ectopic pregnancy in any individual is often unknown, but there are well-known risk factors. These include smoking, a history of pelvic inflammatory disease, conception by in vitro fertilization, gynecologic surgery, current use of intrauterine devices, tubal ligation, or a previous ectopic pregnancy.
Symptoms of an ectopic pregnancy include amenorrhea, or a missed menstrual period, pelvic pain, and vaginal bleeding. Typically, for an ectopic pregnancy in the fallopian tube, pressure increases as the tube stretches around 6-8 weeks into the pregnancy. But if the ectopic pregnancy happens in a place with a lot of space for the embryo to grow, pain and bleeding might not happen until several weeks later.
A physical exam might show a palpable mass near the uterus and abdominal tenderness. But these symptoms mimic a normal pregnancy, and that can contribute to a delay in diagnosis. Diagnosis of an ectopic pregnancy can vary based on a woman's health. It's important to establish that she's hemodynamically stable, meaning her vital signs are within normal limits, with no evidence of hypotension or tachycardia. If the woman is hemodynamically unstable, then immediate surgery might be needed to diagnose and treat the ectopic pregnancy.
If the woman is hemodynamically stable, then serial hCG testing can be done to ensure that levels are doubling approximately every two days, which is typical in an early pregnancy. In addition, transvaginal ultrasound can be used to image the inside of the uterus to see whether or not there's intrauterine pregnancy, which is typically visible by week 5 or 6 of the pregnancy. The transvaginal ultrasound can also help identify an ectopic pregnancy based on signs like excess fluid in the peritoneal cavity.
In a hemodynamically stable woman whose ectopic pregnancy is diagnosed early and the HCG is already declining, treatment might include close monitoring of the woman's health with serial HCG measurements, with no additional medications or procedures. If the ectopic pregnancy is identified later, then methotrexate can be used to terminate the pregnancy. In a hemodynamically unstable patient, a salpingostomy might be done.
That's where the fallopian tube is opened up to remove the pregnancy, and then closed at the end of surgery. Alternatively, a cellpingectomy can be done, which is where the fallopian tube is completely removed. Alright, as a quick recap, an ectopic pregnancy happens when a fertilized egg implants somewhere other than the endometrium of the uterine cavity. Risk factors include smoking, pelvic inflammatory disease, in vitro fertilization, pelvic surgery, Intrauterine devices. tubal ligation, and previous episodes of ectopic pregnancy.
Treatment depends on whether the woman is hemodynamically stable or not, and might include close monitoring, methotrexate, or surgery.