Ectopic Pregnancy

How Does Pregnancy Normally Occur?

In order for a woman to become pregnant, at least one of her ovaries must release a mature ovum. This ovum then remains in the fallopian tube for some time while it awaits fertilization. If it is successfully fertilized by a sperm during this time, the fertilized ovum will eventually move into the uterus and become implanted in the endometrial lining of the uterus which has become thickened with blood in anticipation of this very event. Once it has become implanted in the uterine endometrium and barring any subsequent complications, the embryo will then continue to grow until it is delivered through the birth canal. This is how a normal or uterine pregnancy takes place.

What Is An Ectopic Pregnancy?

Just as the embryo becomes implanted within the uterine cavity, it is perfectly possible for it to become implanted in another location altogether. Such pregnancies are known as ectopic pregnancies. The most common site for implantation outside the uterus is the fallopian tube. However, it is not unheard of for the embryo to become implanted in locations such as the ovary, fimbriae, cervix and even the abdomen. Such pregnancies do not always produce symptoms but can be very painful when they do.

Under What Conditions Does This Happen? What Are The Risk Factors?

Any woman of childbearing age could potentially suffer an ectopic pregnancy. The underlying causes for this are not well understood. However, there are a number of well-recognized risk factors. The list below enumerates some of these risk factors:

• The risk increases with the age of the woman.
• Smoking.
• Having a history of ectopic pregnancy raises the risk of suffering a repeat.
• Any factors that hinder the movement of the ovum through the fallopian tube. This includes tubal ligation for prevention of pregnancy or even certain contraceptives that can affect the character of the fallopian tube, making it difficult for the ovum to travel into the uterus and thus, increasing the probability of implantation within the tube itself. In general, any condition like surgery or infection that gives rise to inflammation, scarring, obstruction or damage in the fallopian tube can increase the probability of developing an ectopic pregnancy.
• Pelvic inflammatory disease (PID) is one of the most common risk factors.
• Sexually transmitted diseases such as chlamydia.
• Endometriosis.
• Presence of scars from surgery in the pelvic area. Examples of such procedures include a Caesarean section for a previous pregnancy or an appendectomy.
• Having a history of procedures such as dilation and curettage for abortion, miscarriage or other reasons.
• Using assisted reproductive techniques or fertility drugs can increase the likelihood of developing an ectopic pregnancy. In fact, such methods increase the likelihood of developing what a ‘heterotopic’ pregnancy which is otherwise extremely rare in nature. In such instances, one embryo may implant in the uterus while the other implants elsewhere.
• When pregnancy occurs despite using contraceptive measures such as intrauterine devices.
• Having a medical condition or a birth defect that affects the structure or shape of organs like the fallopian tubes.
• Some studies have found that women are more likely to suffer ectopic pregnancies in their first pregnancy as compared to subsequent ones.

How Can I Identify An Ectopic Pregnancy?

In most cases, women are usually not aware that they have developed ectopic pregnancies. In instances where symptoms are present, they are usually non-specific and the actual cause is only clearly identifiable after performing some tests. An ectopic pregnancy may also share some of the typical symptoms of a normal uterine pregnancy or even a miscarriage. Generally, symptoms manifest between 4 to 8 weeks following the last menstrual bleeding. Here are some of the indications to look out for:

• Vaginal bleeding.
• Nausea and vomiting.
• Abdominal cramps.
• Feeling faint.
• Pain that may even radiate to the shoulder or neck.
• Tenderness in the cervix.
• Diarrhea.

What Are The Different Kinds Of Ectopic Pregnancy?

The fertilized ovum could implant in any of a number of possible locations outside of the uterus, giving rise to a variety of possible ectopic pregnancies as the list below will briefly explain:

• Tubal Pregnancy: This is the most common form of ectopic pregnancy, wherein the embryo becomes implanted anywhere along the length of the fallopian tube. Depending on which particular section of the fallopian tube is involved, a tubal pregnancy can be of the following types: fimbrial, ampullary, isthmic or interstitial.
• Ovarian Pregnancy: The embryo becomes implanted in the ovary.
• Cervical Pregnancy: The embryo becomes implanted in the cervical canal.
• Abdominal Pregnancy: In such instances, implantation occurs within the abdominal region. For example, the embryo may attach itself to the bowels. This form of ectopic pregnancy represents a greater risk to the mother’s life than other types. However, in very rare instances, live fetuses have been successfully delivered via laparotomy or Caesarean section.
• Caesarean Scar Pregnancy: This is extremely rare. Here, implantation takes place in the scar from prior Caesarean section procedures.

What Are The Complications Of Ectopic Pregnancy?

Ectopic pregnancies may terminate spontaneously. If they do not, they can endanger the life of the mother and even lead to death. This is so because, apart from the uterus, no other site is conducive or properly equipped for the demands of pregnancy, barring exceptional circumstances. An ectopic pregnancy can also negatively impact the mother’s fertility in the future.

If an ectopic pregnancy does progress (which is more likely than spontaneous termination) it could potentially lead to a rupture of the fallopian tube or uterus (as in the case of a Caesarean scar pregnancy). These are medical emergencies and will require immediate hospitalization and surgical intervention.

What Does Diagnosis Involve?

• Medical history, specifically with regard to previous pregnancies, abortions, miscarriages, surgeries or fertility treatments.
• Physical examination.
• Tests for sexually transmitted infections.
• Pregnancy test which usually involves a blood test to look for the presence of the human chorionic gonadotropin and to assess the level of progesterone.
• Transvaginal ultrasonography.
• Laparoscopy.

The Diagnosis Was Positive. What Should I Do?

If an ectopic pregnancy is not detected timely, it can be life-threatening. Once it has been diagnosed, the ectopic tissues need to be removed immediately. This can be done by one of the following methods:

• Medication: If the bleeding is not too severe, drugs such as methotrexate can be prescribed to dissolve the ectopic tissue.
• Laparoscopy: This is used to view the ectopic tissues and the surrounding tubal areas. After this, the ectopic tissues are removed or repaired depending upon the severity of the condition.
• Salpingectomy: If the bleeding is too severe and sudden, emergency surgery is the only sure shot way to avoid further complications. If the fallopian tube has been ruptured extensively, it is removed by a procedure called salpingectomy.

While there are no sure shot ways to gain 100% from ectopic pregnancies, the following methods can help mitigate the risk of developing one:

• Maintain good reproductive health.
• Practice safe sex. Limit the number of sexual partners.
• Always use a condom.
• Go for regular gynecological check-ups to ensure that you are STD-free.
• Refrain from any form of tobacco consumption.

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