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Ectopic Pregnancy: Overview |
The word "ectopic" means "out of place." An ectopic pregnancy is a pregnancy that is not growing in the usual location (the uterine cavity). Ectopic pregnancies can occur in a number of abnormal locations, each with different characteristic growth patterns and treatment options. The most common sites for an ectopic pregnancy are the
Ectopic pregnancies are dangerous. Any growing pregnancy requires a large nutrient source (blood supply) and develops many
communications with the mother's (pregnant woman's) vascular system (blood vessels). The uterus is uniquely designed
to accommodate this development, so that when a pregnancy begins to grow in other surrounding structures the vascular
communication may be inadequate.
Furthermore, as the pregnancy grows in size the uterus dramatically changes shape and size. Surrounding structures
are usually not able to change as readily so they are often damaged or "ruptured" by a contained growing
ectopic pregnancy. When the ectopic pregnancy outgrows the limits of the space enclosing it, there can be life threatening bleeding.
Ectopic pregnancies were initially described in the 11th century and for a long time were universally fatal events
for the mother. Initial treatments (in the old days) were desperate primitive attempts designed to destroy the
growing pregnancy without sacrificing the mother's life. These included
Surgery attempted in the 1800s resulted in a high maternal mortality rate (greater
than 80% of women died from the surgery alone) so it was rarely performed.
Since these times, several developments in the management of ectopic pregnancies have led to remarkable success
in "saving the mother's life."
Further developments recently have resulted in a shift in focus (concern) from saving the mother's life to additionally
"saving the woman's fertility."
The decrease in maternal morbidity (death) from ectopic pregnancy has been largely due to development and refinement
of
At this point in time, gynecologists appropriately attempt to diagnose ectopic pregnancy early (since greater treatment options are available) and treat the ectopic pregnancy in such a way as to maximize fertility and minimize the risk for a future ectopic.
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Ectopic Pregnancy: Incidence Rates & Rick Factors |
In the USA, ectopic pregnancies are reported. This allows some tabulation of incidence
rates and outcomers.
The Centers for Disease Control (CDC) examined ectopic pregnancies occurring during the 17 year period between
1970 and 1987 and noted that the
During this same time period, the
Despite the sharp improvement in the fatality rate by the end of this period of
time, ectopics were still the second leading cause of maternal mortality in the USA (accounting for 12% of all
maternal deaths in 1987).
The reason for the increase in ectopic pregnancy during this time period is not entirely clear. Of the known risk
factors, it is believed that an increased number of cases of sexually transmitted disease (which damage fallopian
tube transport of embryos into the uterus) is responsible for a significant portion of the increased number of
cases of ectopic pregnancy.
Risk factors for ectopic pregnancy that should be recognized include:
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Ectopic Pregnancy: Diagnosis |
Early diagnosis of an ectopic pregnancy
is critically important in terms of outcome. When an ectopic pregnancy is detected early in development, especially
prior to rupture or damage to surrounding tissue, major morbidity is decreased and the treatment options are enhanced.
There is no uniformly accepted diagnostic protocol for the determination of an ectopic pregnancy. Different gynecologists
seem to have protocols that "work for them." These are often modifications of the published flow diagrams
found in the major text books. Some of the common themes are discussed here.
A universal characteristic of a good "early diagnosis" protocol is a "high
index of suspicion." Even in the absence of known risk factors, ectopic
pregnancy may occur as often as 1-2% of pregnancies. If there are multiple risk factors, the risk may be 25% of
pregnancies.
Sensitive blood hCG assays allow very early diagnosis of pregnancy. Typically these assays have a sensitivity of
1-5 mIU/mL so they can detect the occurrence of pregnancy (not location) about 7-8 days after fertilization (a
few days prior to a missed menstrual flow). If the hCG assay is negative (generally less than 5 mIU/mL) then complications
from an ectopic pregnancy are generally thought to be ruled out. Exceptions may occur in unusual circumstances,
such as when one of my patients was treated for an ectopic pregnancy with medication (methotrexate) and she ruptured
a blood vessel from the ectopic pregnancy site after her hCG dropped from a few thousand mIU/mL to negative (less
than 5 mIU/mL). Caution should always prevail.
Other blood concentrations of pregnancy related polypeptides or steroid hormones have been used for the early detection
of ectopic pregnancy. Included are progesterone, early pregnancy factor (EPF), pregnancy specific beta-1 glycoprotein
(SP1), and placental protein 5 (PP 5). These other factors have not been adequately characterized to allow widespread
routine use in ectopic pregnancy detection.
The second most common hormone (hCG is the most common) followed in pregnancy is
progesterone. Unfortunately, there is a wide overlap between circulating
progesterone concentrations in normal intrauterine pregnancy and ectopic pregnancy. Generally, a progesterone concentration
of greater than 25 ng/mL is highly correlated (greater than 95%) with a normal intrauterine pregnancy while a concentration
of less than 5 ng/mL is highly correlated (almost 100%) with an abnormal and nonviable pregnancy. Concentrations
between 10 and 20 ng/mL (the most common concentrations) are of little differential value. Of concern for those
who use 5 ng/mL as an indicator of fetal nonviability are the reports of several women with documented very low
progesterone concentrations (typically thought to be inconsistent with a viable intrauterine pregnancy) who have
gone on to deliver babies at term. These reports force one to reconsider the value of the progesterone concentrations,
and include:
Serial circulating hCG concentrations
are often used to gain insight into the normalcy of an existing pregnancy. A period of intense research characterized
the rate of rise of hCG in normal pregnancy as at least 66% and more often 100% in a 2 day period during the first
6 weeks of pregnancy. If there is a rate of rise of less than 66% in hCG over a 2 day period of time (in early
pregnancy) then this suggests an abnormally growing intrauterine pregnancy or an ectopic pregnancy. Again, there
are several reports of women (up to 10%) who have abnormal rates of rise in hCG and who go on to deliver babies
at term.
It would be ideal to have an "ectopic pregnancy hormone" to check whenever the concern for an ectopic arose. There is active research is
this field, but thus far there are no clinically useful direct tests for ectopic pregnancy. If such a test becomes
available, this would revolutionize the diagnosis of these potentially fatal complications of pregnancy.
If the concern for an ectopic pregnancy is raised by either the woman's history of risk factors, pelvic or adnexal
pain in early pregnancy, or an abnormal doubling of the hCG titers then additional diagnostic intervention is appropriate.
Transvaginal ultrasonography is
a sensitive radiologic test and should be able to detect an intrauterine gestational sac at an hCG concentration
of about 1500 mIU/mL (using the 1st International Reference Preparation) which normally occurs at about 5 weeks
"estimated gestational age" (EGA). The absence of a gestational sac with an hCG concentration of greater
than 1500 mIU/mL suggests either an abnormally developing intrauterine pregnancy or an ectopic pregnancy. Exceptions
do occur. Multiple gestations
have two placentae each producing its own hCG so the concentration of 1500 mIU/mL will occur several days prior
to a singleton gestation at the same EGA. Also, pregnancies with large
placentae may produce hCG concentrations that are greater than expected
for their EGA.
In the absence of pain, evidence
of hemoperitoneum (rupture) or cardiovascular instability a conservative approach is most appropriate if the status
and location of the pregnancy is unclear and the pregnancy is desired by the couple. When it becomes clear that
there is an abnormal or ectopic pregnancy or if the woman becomes less stable then active treatment must be quickly
reevaluated and selected.
If the woman is stable hemodynamically and an abnormal or ectopic pregnancy is diagnosed then one can consider
a dilatation and curettage (D+C) to evacuate the uterine cavity in hope of finding or eliminating the abnormal
pregnancy. If a D+C is performed and products of conception (placental villi) are identified or the hCG titers
start to fall, then an incomplete or missed abortion is diagnosed. If no villi are identified, then an ectopic
pregnancy is very likely (occasionally one will not be able to disrupt an early small intrauterine pregnancy even
with a thorough D+C). One can consider checking an hCG concentration to confirm that the level is not decreasing
after the D+C and then consider active management of the likely ectopic pregnancy.
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Ectopic Pregnancy: Treatment Options |
Once the decision has been made to treat a pregnancy as an ectopic (or a nonviable
intrauterine pregnancy) the physician will attempt to eliminate the potentially dangerous pregnancy to minimize
maternal risk. The physician will also try to preserve as much future fertility as possible.
Three primary types of treatment are available for an ectopic pregnancy. These include surgical management, medical
management, and expectant management.
The most common treatment is surgical.
Surgery allows a rapid and usually definite resolution of the pregnancy, however the woman does assume the usual
surgical risks. Medical management primarily involves the use of methotrexate, which has gained popularity as a
way of avoiding surgical risk. Methotrexate management results in destruction of the growing pregnancy but is comparatively
slow-- often taking 4-6 weeks for complete resolution of the ectopic pregnancy. Medical management risks rupture
of the ectopic over this relatively long course of management. Expectant management is essentially observation
and monitoring without active treatment, understanding that up to 25% of ectopic pregnancies will resolve on their
own. The risk of expectant management is rupture of the ectopic pregnancy during the observation period.
(1) Surgery is the most common management of an ectopic pregnancy.
Treatment for all ruptured ectopic pregnancies is surgery.
If the woman has a ruptured ectopic pregnancy and she is hemodynamically unstable then surgery is required and
laparoscopy is contraindicated. In this situation, a laparotomy (larger incision with open surgery) should be performed
and usually a (partial) salpingectomy (removal of the tube) is performed regardless of whether significant damage
to the tubal lumen is suspected. The removal of the damaged tube allows rapid control of bleeding and the best
chance for continued hemostasis throughout the postoperative period.
If the woman has a ruptured ectopic pregnancy and is hemodynamically stable, then surgery is required and laparoscopy
is not absolutely contraindicated. The decision on whether a laparoscopy or laparotomy is to be performed depends
on the specific clinical details, the couple's desires, the surgeon's laparoscopic expertise, and the operating
room's equipment. The advantage of laparoscopy is in terms of postoperative recovery for the woman having surgery.
The same type of surgery would be done regardless of the size of the incisions made to perform the surgery.
If the woman has a non ruptured ectopic pregnancy, then the treatment options are broadened to include nonsurgical
management. If surgery is decided upon, then the decision must be made in terms of laparoscopy or laparotomy. This
decision depends primarily on the surgeon's expertise with laparoscopy and the operating room's laparoscopic equipment.
Generally, women prefer the shorter recovery period, reduction in postoperative pain, and smaller incisions in
the abdomen associated with laparoscopy.
It should be emphasized that either approach (laparoscopy or laparotomy) is (medically) acceptable and capable
of achieving the goals of decreasing morbidity and increasing future fertility. If the surgeon identifies an ectopic
by laparoscopy yet is not comfortable in performing the necessary surgery on the ectopic pregnancy site through
the laparoscope (and cannot call for an intraoperative consult with someone able to do the surgery via laparoscopy),
then the appropriate decision is to perform the surgery by laparotomy. Occasionally one hears about a patient taken
for diagnostic laparoscopy to evaluate an ectopic pregnancy, an ectopic pregnancy is identified, the surgeon is
not comfortable with removing the ectopic pregnancy via laparoscopy, the surgeon desires that the woman's pregnancy
be treated laparoscopically, and so the case is concluded so that the patient can be transferred postop to a surgeon
who will remove the ectopic pregnancy laparoscopically. This should be discouraged since there is a chance for significant morbidity if the ectopic ruptures and the woman
requires a second surgery. The surgeon in this situation would hopefully have counseled the patient preoperatively
that if an ectopic is identified then the decision will be to proceed to definitive management by laparotomy.
Surgical treatment options for removal of an ectopic pregnancy partially depend on the location of the ectopic
pregnancy.
Surgical treatment options for the removal of an ectopic pregnancy also partially depend on the prior history of tubal disease, infertility, ectopic pregnancy and the couple's desires. Although a bit controversial (due to the lack of strong factual data), consideration should include:
(2) Methotrexate has become popular in selected cases of ectopic pregnancy.
Unruptured tubal ectopic pregnancies in women who elect conservative (saving the tube) management may be able to
be treated with methotrexate. The current (somewhat limited) factual data suggests that methotrexate management
and conservative surgical management have similar success in terms of subsequent tubal patency, fertility, ectopic
pregnancy and intrauterine pregnancy. One classic article on these rates when using the single IM dosing protocol
is a prospective clinical trial of 120 women (published in 1993) where Drs. Stovall and Ling report
The first experience with methotrexate was in Japan (Dr. Tanaka) in 1982 and the
first use of methotrexate in the USA (with Dr. Steven Ory) was in 1986. Ectopic pregnancy is not
an approved FDA indication for methotrexate. FDA approved uses of methotrexate
include cancer treatment (including
trophoblast disease, breast cancers and leukemia), psoriasis, and rheumatoid arthritis.
Methotrexate is a mixture containing at least 85% of "4-amino-10-methylfolic acid," is a folic acid antagonist
(reversibly inhibiting dihydrofolate reductase which normally reduces folic acid to tetrahydrofolic acid), and
consequently interferes with DNA synthesis and cell reproduction. Leucovorum calcium is a derivative of tetrahydrofolic
acid which replaces the missing active form of folic acid to block the effects of methotrexate (the so called "rescue").
Methotrexate crosses the placenta and is found in breast milk. The medication is absolutely
contraindicated in pregnant women intending to carry the pregnancy to term.
Therefore, many treatment protocols require pregnant women with either an abnormally growing intrauterine pregnancy
or an ectopic pregnancy to have a pretreatment dilatation and curettage (D+C). Others simply include in the consent
form for methotrexate that it is agreed to undergo definitive surgical management of the pregnancy if the methotrexate
fails to resolve it.
Peak serum concentrations of methotrexate occur 2 hours after an IM dose, and have a serum half life of about 2-4
hours. Methotrexate does not seem to be appreciably metabolized with up to about 90% of an IV dose excreted via
the kidneys within 24 hours.
The single IM injection of 50 mg per meters squared (body surface area) for the treatment of ectopic pregnancy
is associated with (uncommon) transient side effects but persistent complications are virtually absent. Major complications of methotrexate at doses used
for the FDA indications include
Contraindications to the use of methotrexate generally include
Drug interactions with methotrexate can occur and may enhance toxicity. This usually occurs with high doses of methotrexate but should be avoided whenever able. The drugs known to interact with methotrexate include:
The initial protocols utilized a multiple dose regimen with methotrexate (typically
1 mg/kg IM) and leukovorum (citrovorum, 0.1 mg/kg IM) on alternate days for up to 4 doses of methotrexate. Side
effects were seen in about 5% of women and typically included gastrointestinal upset (stomatitis [oral ulcers],
gastritis, diarrhea, transient elevation in liver enzymes). Significant side effects involving bone marrow suppression,
dermatitis and pleuritis have been very uncommon. Failure to adequately treat the ectopic pregnancy has been about
3-5%. Tubal rupture of the ectopic pregnancy occurs in less than 5%.
Currently the most popular protocol
uses far less methotrexate and does not require citrovorum as a rescue. A single IM dose of methotrexate (50 mg
per meters squared [surface area]) is administered with few side effects (occasional stomatitis, gastritis and
diarrhea) and virtually no serious side effects (bone marrow suppression, dermatitis, pleuritis).
Additional criteria in selecting
appropriate candidates for methotrexate management of an ectopic pregnancy might include
Once a candidate has been selected, the following protocol should be adhered to
Then the medication should be given as 50 mg per meters squared (surface area)
IM (divided dosed if desired)-- this will be considered DAY 1.
On DAY 4, an hCG titer should be obtained (the hCG concentration will continue to increase for a few days following
methotrexate administration)
On DAY 7, an hCG titer should be obtained
If the DAY 7 hCG concentration reflects a drop from the maximal hCG concentration (at DAY 4) of at least 15% then
weekly hCG titers should be obtained until negative. If the DAY 7 hCG concentration did not drop from the maximal
hCG concentration (at DAY 4) by 15% or if the hCG titer begins to rise on subsequent weeks then consideration of
another dose of 50 mg per meters squared is considered.
DAY 7 blood work does not need to include a CBC and chemistry profile, but many physicians (including myself) like
to confirm that the RBCs, WBCs, platelets and liver function tests have not changed. Using this dose of methotrexate,
I have never seen a significant change in any of these parameters.
Important Note #1: Many women
will have adnexal discomfort or pain about 3 or 4 days following administration of methotrexate. Several physicians
refer to this as "methotrexate pain"
but rupture of the existing ectopic pregnancy must be considered and ruled out.
Important Note #2: Non tubal ectopic pregnancies are often managed
with methotrexate. Cervical, abdominal and cornual pregnancies are very dangerous and require careful consideration
of existing treatment options. Severe bleeding can be associated with methotrexate or surgical treatments and very
close observation until the pregnancy is resolved is absolutely necessary.
(3) Expectant management of an ectopic pregnancy is generally discouraged.
Expectant management of ectopic pregnancy may be appropriate in selected situations. The risk of rupture for an ampullary ectopic pregnancy is
thought to be roughly 10% for
circulating hCG concentrations less than 1000 mIU/mL.
The risk of rupture for an isthmic
ectopic pregnancy is thought to be about 10%
for a circulating hCG concentration less than 100 mIU/mL (since the space in which isthmic pregnancies must grow is far smaller than for ampullary
pregnancies). Therefore, consideration of expectant management for an ectopic pregnancy when hCG concentrations
are low is possible. There is always a risk of rupture until the pregnancy has been completely resolved.
Criteria that are occasionally used in deciding on expectant management include
I have generally discouraged the use of expectant management of ectopic pregnancy unless the hCG titer is spontaneously declining since the risk of serious morbidity with rupture appears to be increased (even if only slightly).
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Dr. Daiter's Background |
| Dr. Eric Daiter graduated from the University of Pennsylvania, where he
was awarded an academic scholarship and was enlisted into the University Scholar's Program and the Benjamin Franklin
Scholar's Program. Dr. Daiter graduated medical school at Temple University Medical School in Philadelphia and completed the Obstetrics and Gynecology residency program at Albert Einstein College of Medicine in New York. He completed his Reproductive Endocrinology and Infertility fellowship at the Hospital of the University of Pennsylvania. He has considered a career as a physician scientist in research medicine and has published several articles on molecular events that occur during the human embryo's implantation into the uterus. Dr. Daiter entered private practice in 1994, where he joined a successful referral based infertility practice and further developed his clinical skills. Dr. Daiter emphasizes the basic principles of infertility patient care, including the importance of highly personalized, cost considerate, state of the art, one on one care for his patients. He specializes in all aspects of In Vitro Fertilization, with a patient success rate among the highest in the state. He has performed several hundred advanced operative laparoscopic and hysteroscopic surgeries, utilizing the most modern laser techniques. |