What is Ectopic pregnancy?
- Ectopic pregnancy literally means “out of place” pregnancy; it occurs when a fertilized egg implants at a site outside the uterine cavity.
- 95% of all ectopic pregnancies implant within the fallopian tube. Non tubal implantation sites are uncommon and may involve the ovary, cervix, C-Section scar or abdominal cavity.
Why do ectopic pregnancies occur?
All normal pregnancies begin within the fallopian tube when an egg is fertilized by sperm. The fertilized egg remains in the tube for 3-5 days and is transported into the uterus by contractions of the tube and by the sweeping movement of fine, hair-like cells (cilia) lining the tube.
Any condition causing inflammation of the tube can damage the cilia lining the fallopian tube. This can compromise the process of transporting the embryo through the tube, resulting in implantation of the embryo outside the uterine cavity.
How common is tubal pregnancy?
Ectopic pregnancies occur in about 2% of all reported pregnancies representing a 5-6 fold increase since 1970.
Risks factors associated with tubal pregnancy:
- Previous pelvic infection – 4 fold increased risk.
- History of previous tubal pregnancy.
- Previous tubal surgery or reversal of tubal ligation.
- Infertility, ovulation induction therapy using Clomiphene or injectable Gonadotropins.
- IVF is associated with a 2-4% incidence of ectopic pregnancy.
- Older age (over age 35) – 3 to 4 fold increase in the risk of tubal pregnancy as compared with women younger than age 25.
- Smoking – 2-4 fold that of nonsmokers.
- Intrauterine device (IUD) – more so with those containing progesterone.
Diagnosis of tubal pregnancy
- Symptoms – Ectopic pregnancy should be considered in any woman of reproductive age, presenting with pain, abnormal bleeding or irregular periods.
- Beta HCG level – A simple blood pregnancy test (beta HCG and progesterone levels) early in pregnancy can be utilized to monitor the pregnancy.
- Ultrasound – When the beta HCG reaches a level of 1500 miu/ml, an ultrasound can determine whether the pregnancy is located within the uterus (fig. 1) or outside (fig.2 - ectopic pregnancy).
In infertility practices, tubal pregnancies are diagnosed relatively early because patients are closely monitored and are tested for the pregnancy marker – the Beta HCG (Human Chorionic Gonadotropin) level – when their menstrual period is expected. Once a positive pregnancy test is detected, the HCG level is checked every 2-3 days. It normally doubles approximately every 2 days, so, lower then expected levels may indicate an ectopic pregnancy or an impending miscarriage.
When the beta HCG reaches a level of 1500 miu/ml, a pregnancy sac should be detected by vaginal ultrasound, and failure to see the pregnancy inside the uterus is presumptive of an ectopic pregnancy.
In rare cases, especially when the woman undergoes IVF, a tubal pregnancy may coexist with a normal uterine pregnancy (heterotopic pregnancy). Once the tubal pregnancy is removed, there is more than a 70% probability that the uterine pregnancy will continue to delivery.
Treatment of ectopic pregnancy
Early diagnosis by ultrasound and assessment of the woman’s condition is critical in determining the appropriate care.
The goal of treatment for ectopic pregnancy is to preserve the woman’s fertility and to treat only the tubal pregnancy
There are 2 treatment options:
- Medical treatment
- Surgical treatment
Occasionally, the ectopic pregnancy will simply deteriorate spontaneously (much like a miscarriage) and will be absorbed by the body. However, the tube may also rupture if not treated in time.
Medical treatment of ectopic pregnancy
Medical treatment of ectopic pregnancy involves injections of a drug called Methotrexate to stop the growth of the embryo. You are a good candidate for the treatment if:
- The ectopic is discovered early before it ruptures.
- Beta HCG hormone level is less than 15,000.
- The size of the pregnancy in the tube is less than 4 cm.
- No heart beat is detected by ultrasound.
- You have no pain.
Once you receive your Methotrexate injection, you will be closely monitored with several pregnancy hormone levels (HCG) to make sure the HCG begins to drop. You will then undergo weekly testing for HCG level until your HCG level decreases to 0 indicating that the problem has been resolved. If after a week, your HCG hormone level remains high, you will be given another injection of Methotrexate while continuing to monitor the HCG levels. If the HCG hormone level continues to rise, laparoscopic surgery will be necessary to remove the ectopic pregnancy
Surgical treatment of ectopic pregnancy
Laparoscopic surgery to remove the ectopic pregnancy while preserving the tube depends on the site of implantation within the tube and on whether or not the pregnancy has ruptured.
Laparoscopic surgery is indicated if:
- You experience significant pain.
- The tubal pregnancy is ruptured and is bleeding into the abdominal cavity.
- The tubal pregnancy is too large (greater than 4 cm).
- A heartbeat is seen within the pregnancy sac.
- The beta HCG level is very high.
- This is a recurrent ectopic pregnancy in the same tube.
- You were given Methotrexate but the tubal pregnancy is continuing to grow.
How is the surgery performed?
During laparoscopy a thin fiber-optic tube, attached to a video camera, is inserted into the abdomen, through a small incision in the belly button. The ectopic pregnancy is seen as a bulge in the fallopian tube (fig. 3). An incision is made over the tubal pregnancy and the pregnancy is evacuated leaving the tube intact. No stitching is necessary to close the tube. If the pregnancy is implanted in the narrowest portion of the tube, closest to the uterus, partial (segmental) removal of the involved portion of the tube is often necessary; keeping the option of reattaching the blocked segments of the tubes later (tubal reanastomosis). Complete removal of the tube (salpingectomy) is necessary when the tubal pregnancy is ruptured or when there is history of previous pregnancy in the same tube..
The goal of laparoscopic management of an unruptured ectopic pregnancy is to remove only the pregnancy sac and preserve the fallopian tube when possible. An incision is made in the tube over the bulging pregnancy sac (fig. 4). The pregnancy sac is identified and extracted from the tube (fig. 5). The bulge in the fallopian tube is no longer present and the tubal incision (fig. 6) will heal in a relatively short period of time. There is a 20 % risk of recurrent ectopic in the same tube or another ectopic in the opposite tube.
In more severe cases, the pregnancy causes the tube to swell (fig. 7) and rupture, resulting in abdominal bleeding (fig. 8). Laparoscopic surgery should be immediately performed to remove the affected tube (fig. 9).
Monitoring the treatment
After surgical or medical treatment of the ectopic, your doctor will order a weekly beta HCG level for several weeks until the Beta-HCG hormone level is negative, indicating that the problem is resolved.
If your blood type is Rh negative you will be given Rhogam to prevent sensitization of your immune system in subsequent pregnancies.
What are the complications of tubal pregnancy?
- Ruptured ectopic is a medical emergency, and if unrecognized, may result in death.
- Ectopic pregnancies may cause other serious complications, such as bleeding, infection and infertility.
- There is a risk that your next pregnancy may be complicated by another tubal pregnancy.
What about future pregnancies?
- You may experience more difficulty conceiving, especially if you were already receiving fertility treatment.
- Once you had an ectopic pregnancy you have about 15-20% chance of having another.
- Contact your doctor at once if you become pregnant again, so that he can schedule tests and an early ultrasound to make sure your pregnancy is implanted inside the uterus.
- Infertility patients with a history of tubal pregnancy should consider In Vitro Fertilization (IVF).