In a normal
pregnancy, a fertilized egg travels through a
fallopian tube to the
uterus. The egg attaches in the uterus and starts to
grow. But in an ectopic pregnancy, the fertilized egg attaches (or implants)
someplace other than the uterus, most often in the fallopian tube. (This is why
it is sometimes called a tubal pregnancy.) In rare cases, the egg implants in
an ovary, the cervix, or the belly.
There is no way to save an ectopic pregnancy. It
cannot turn into a normal pregnancy. If the egg keeps growing in the fallopian
tube, it can damage or burst the tube and cause heavy bleeding that could be
deadly. If you have an ectopic pregnancy, you will need quick treatment to end
it before it causes dangerous problems.
What causes an ectopic pregnancy?
An ectopic
pregnancy is often caused by damage to the fallopian tubes. A fertilized egg
may have trouble passing through a damaged tube, causing the egg to implant and
grow in the tube.
Things that make you more likely to have
fallopian tube damage and an ectopic pregnancy include:
Smoking. The more you smoke, the higher your
risk of an ectopic pregnancy.
In the first few weeks, an
ectopic pregnancy usually causes the same symptoms as a normal pregnancy, such
as a missed menstrual period, fatigue, nausea, and sore breasts.
The key signs of an ectopic pregnancy are:
Pelvic or belly pain. It may be sharp on one
side at first and then spread through your belly. It may be worse when you move
or strain.
Vaginal bleeding.
If you think you are pregnant and you have these
symptoms, see your doctor right away.
How is an ectopic pregnancy diagnosed?
A urine
test can show if you are pregnant. To find out if you have an ectopic
pregnancy, your doctor will likely do:
A pelvic exam to check the size of your
uterus and feel for growths or tenderness in your belly.
A blood
test that checks the level of the pregnancy hormone (hCG). This test is
repeated 2 days later. During early pregnancy, the level of this hormone
doubles every 2 days. Low levels suggest a problem, such as ectopic pregnancy.
An
ultrasound. This test can show pictures of what is
inside your belly. With ultrasound, a doctor can usually see a pregnancy in the
uterus 6 weeks after your last menstrual period.
How is it treated?
The most common treatments are
medicine and surgery. In most cases, a doctor will treat an ectopic pregnancy
right away to prevent harm to the woman.
Medicine can be used if
the pregnancy is found early, before the tube is damaged. In most cases, one or
more shots of a medicine called methotrexate will end the pregnancy. Taking the
shot lets you avoid surgery, but it can cause side effects. You will need to
see your doctor for follow-up blood tests to make sure the shot worked.
For a pregnancy that has gone beyond the first few weeks, surgery is
safer and more likely to work than medicine. If possible, the surgery will be
laparoscopy (say "lap-uh-ROSS-kuh-pee"). This type of
surgery is done through one or more small cuts (incisions) in your belly. If
you need emergency surgery, you may have a larger incision.
What can you expect after an ectopic pregnancy?
Losing a pregnancy is always hard, no matter how early it happened. Take
time to grieve your loss, and get the support you need to make it through this
time.
You could be at risk for
postpartum depression after an ectopic pregnancy. If
you have symptoms of depression that last for more than 2 weeks, be sure to
tell your doctor so you can get the help you need.
It is common to
worry about your fertility after an ectopic pregnancy. Having an ectopic
pregnancy does not mean that you can't have a normal pregnancy in the future.
But it does mean that:
You may have trouble getting pregnant.
You are more likely to have another ectopic pregnancy.
If you get pregnant again, be sure your doctor knows that
you had an ectopic pregnancy before. Regular testing in the first weeks of
pregnancy can find a problem early or let you know that the pregnancy is
normal.
Common causes of
fallopian tube damage that may lead to an ectopic pregnancy include:
Smoking. Women who smoke or who used to smoke
have higher rates of ectopic pregnancy. The more you smoke, the higher your
risk.1 Smoking is thought to damage the fallopian
tubes' ability to move the fertilized egg toward the uterus.
Fallopian tube surgery, often used to reverse a
tubal ligation or to repair a scarred or blocked
tube.
A previous ectopic pregnancy in a fallopian tube.
Although pregnancy is rare after a
tubal ligation or with an
intrauterine device (IUD), those pregnancies that do
develop have an increased chance of being ectopic.2
Ectopic risk is also higher for women who get pregnant while using
progestin-only birth control pills or implants.3
Symptoms
An early
ectopic pregnancy often feels like a normal pregnancy.
A woman with an ectopic pregnancy may experience common signs of early
pregnancy, such as:
A missed menstrual period.
Tender
breasts.
Fatigue.
Nausea.
Increased
urination.
As an
ectopic pregnancy progresses, however, other symptoms develop, including:
Abdominal or pelvic pain, usually 6 to 8 weeks
after a missed period.4 Pain may get worse with
movement or straining. It may occur sharply on one side at first and then
spread throughout the pelvic region.
Shoulder pain caused by
bleeding into the abdomen under the
diaphragm. The bleeding irritates the diaphragm and is
experienced as shoulder pain.
Symptoms of
miscarriage often are similar to symptoms experienced
in early ectopic pregnancy. For more information, see the topic
Miscarriage.
What Happens
Normally, at the beginning of a
pregnancy, the fertilized egg travels from the
fallopian tube to the
uterus, where it implants and grows. In about 2% of
diagnosed pregnancies, however, the fertilized egg attaches to an area outside
of the uterus, which results in an
ectopic pregnancy (also known as a tubal pregnancy or
an extrauterine pregnancy).5
An
ectopic pregnancy cannot support the life of a fetus for very long. However, an
ectopic pregnancy can grow large enough to rupture the area it occupies, cause
heavy bleeding, and endanger the mother. A woman with signs or symptoms of an
ectopic pregnancy requires immediate medical
care.
In most ectopic pregnancies, the fertilized egg has
implanted in a fallopian tube.
On rare occasions:
The egg attaches and grows in an ovary, the
cervix, or the abdominal cavity (outside of the
reproductive system).
One or more eggs
grow in the uterus, and one or more grow in a fallopian tube, the cervix, or
the abdominal cavity. This is called a
heterotopic pregnancy.
Although extremely rare, there are reports of women
developing abdominal ectopic pregnancies after surgical removal of the uterus
(hysterectomy).6
Ectopic
pregnancy can damage the fallopian tube, which can make it difficult to become
pregnant in the future.
Ectopic pregnancies are usually detected
early enough to prevent life-threatening complications such as severe bleeding.
A
ruptured ectopic pregnancy requires emergency surgery
to prevent heavy bleeding into the abdomen. The affected tube is partially or
fully removed. For more information, see the Surgery section of this
topic.
What Increases Your Risk
Factors that can increase
your risk of having an
ectopic pregnancy include:1
Past or
present cigarette smoking, which increases your risk of having an ectopic
pregnancy. The more you smoke, the higher the risk. Experts suspect that
smoking affects fallopian tube function.1, 3
Use of a copper
intrauterine device (IUD) for birth control lowers
your overall risk for ectopic pregnancy. This is because you are very unlikely
to conceive with an IUD-only 1 to 6 per 1,000 progestin IUD users become
pregnant per year. (However, these rare pregnancies are more likely than usual
to be ectopic.)7
Medical treatments and procedures that can increase your risk of having an
ectopic pregnancy include:
Previous fallopian tube surgery to treat
infertility or to reverse a
tubal ligation.
A tubal ligation failure.
On the rare occasion that pregnancy happens after a sterilization surgery,
there is a higher-than-usual risk that the pregnancy is ectopic.
A
progestin-only birth control failure (pills or implants).3
Infection after any kind of surgery done on the uterus or fallopian tubes. This
can lead to scar tissue.8
Ectopic pregnancy has been linked to the use of medicine
used to make the ovary release multiple eggs (superovulation). Experts do not yet know whether this
is because many women using it already have fallopian tube damage or because of
the medicine itself.1
If you become pregnant and are at high risk for ectopic pregnancy, you will
be closely monitored. Health professionals do not always agree about which risk
factors are serious enough to watch closely. However, research suggests that
risk is serious enough if you have had a tubal surgery or an ectopic pregnancy
before, had DES exposure before birth, have known fallopian tube problems, or
have a pregnancy with an intrauterine device (IUD) in place.1
When To Call a Doctor
If you are pregnant, be alert to
the symptoms that may indicate an
ectopic pregnancy, especially if you are at risk.
If you have vaginal bleeding or severe pain in your abdomen (with or without positive pregnancy test results or
during treatment for ectopic pregnancy):
Call your health professional immediately.
Rest as much as possible.
Avoid
strenuous activity until your symptoms have been evaluated by a health
professional.
If you have minor abdominal pain that does not seem to be
going away, call your health professional. For any abdominal pain or vaginal
bleeding, see the following topics to evaluate your symptoms:
Watchful waiting means taking a wait-and-see
approach.
Because an ectopic pregnancy can become
life-threatening, watchful waiting at home is not safe.
Call your health professional immediately if you have symptoms of an ectopic
pregnancy.
Who To See
The following health professionals can evaluate you for an
ectopic pregnancy:
Most
ectopic pregnancies can be detected using a pelvic
exam, ultrasound, and blood tests. If you have symptoms of a possible ectopic
pregnancy, you will have:
A pelvic exam, which can detect tenderness in
the
uterus or
fallopian tubes, less enlargement of the uterus than
expected for a pregnancy, or a mass in the pelvic area.
A
pelvic ultrasound (transvaginal or abdominal), which
uses sound waves to produce a picture of the organs and structures in the lower
abdomen. A transvaginal ultrasound is the most dependable way to show where a
pregnancy is. A pregnancy in the uterus is visible 6 weeks after the last
menstrual period. An ectopic pregnancy is likely if there are no signs of an
embryo or fetus in the uterus but hCG levels are
elevated or rising.
Two or more blood tests of pregnancy hormone
(human chorionic gonadotropin, or hCG) levels, taken 48
hours apart. During the early weeks of a normal pregnancy, hCG levels double
every 2 days. Low or slowly increasing levels of hCG in the blood suggest an
early abnormal pregnancy, such as an ectopic pregnancy or a
miscarriage. If hCG levels are abnormally low, further
testing is done to find the cause.
Sometimes a surgical procedure using
laparoscopy is used to look for an ectopic pregnancy.
An ectopic pregnancy after 5 weeks can usually be diagnosed and treated with a
laparoscope. But laparoscopy is not often used to diagnose a very early ectopic
pregnancy, because ultrasound and blood pregnancy tests are very
accurate.
Follow-up testing after treatment
During the week
after treatment for an ectopic pregnancy, your hCG (human chorionic
gonadotropin) blood levels are tested several times. Your health professional
will look for a drop in hCG levels, which is a sign that the pregnancy is
ending (hCG levels sometimes rise during the first few days of treatment, then
drop). In some cases, hCG testing continues for weeks to months until hCG
levels drop to a low level.
What to think about
If you become pregnant and are at high risk for an ectopic pregnancy, you will be
closely monitored. Health professionals do not always agree about which risk
factors are serious enough to watch closely. But research suggests that risk is
serious enough if you have had a tubal surgery or an ectopic pregnancy before,
had
DES exposure before birth, have known fallopian tube
problems, or have a pregnancy with an
intrauterine device (IUD) in place.1
A urine pregnancy test-including a
home pregnancy test-can accurately diagnose a
pregnancy but cannot detect whether it is an ectopic pregnancy. If a urine
pregnancy test confirms pregnancy and an ectopic pregnancy is suspected,
further blood testing or ultrasound is needed to diagnose an ectopic
pregnancy.
Treatment Overview
In most cases, an
ectopic pregnancy is treated right away to avoid
rupture and severe blood loss. The decision about which treatment to use
depends on how early the pregnancy is detected and your overall condition. For
an early ectopic pregnancy that is not causing bleeding, you may have a choice
between using medicine or surgery to end the pregnancy.
Medication. Using
methotrexate to end an ectopic pregnancy spares you
from an incision and
general anesthesia. But it does cause side effects and
can take several weeks of hormone blood-level testing to make sure that
treatment has been successful. Methotrexate is most likely to work:
When your pregnancy hormone levels (human chorionic gonadotropin,
or hCG) are low (less than 5,000).
During the first 6 weeks of
pregnancy.
When the embryo has no heart activity.
Surgery. If you have an ectopic
pregnancy that is causing severe symptoms, bleeding, or high hCG levels,
surgery is needed. This is because medicine is not likely to work and a rupture
becomes more likely as time passes. Whenever possible,
laparoscopic surgery that uses a small incision is
done. For a
ruptured ectopic pregnancy, emergency surgery is
needed.
Expectant management. For an early
ectopic pregnancy that appears to be naturally miscarrying (aborting) on its
own, you may not need treatment. Your health professional will regularly test
your blood to make sure that your pregnancy hormone (hCG, or human chorionic
gonadotropin) levels are dropping. This is called
expectant management.
Ectopic pregnancies
can be resistant to treatment.
If hCG levels do not drop or bleeding does not
stop after taking methotrexate, your next step may be surgery.
If
you have surgery, you may take methotrexate afterward.
Methotrexate is usually the first treatment
choice for ending an early ectopic pregnancy. Regular follow-up blood tests are
needed for days to weeks after the medicine is injected.
There are
different types of surgery for a tubal ectopic pregnancy-when possible, only a
slit is made in the fallopian tube (salpingostomy), rather than removing a
section of the tube (salpingectomy).
On average, salpingostomy is
equal to methotrexate (for an early ectopic pregnancy) in terms of being
effective and preserving a woman's ability to become pregnant in the
future.9
Although surgery is a faster treatment, it can cause scar
tissue that could cause future pregnancy problems. Tubal surgery may damage the
fallopian tube, depending on where and how big the embryo is and the type of
surgery needed.
Surgery may be your only treatment option if an ectopic
pregnancy has gone past 6 weeks or if you have internal bleeding.
Prevention
If you smoke, quitting will lower your
risk of
ectopic pregnancy. Women who smoke or who used to
smoke have higher rates of ectopic pregnancy. The more you now smoke, the
higher your risk is.1
Using safe sex practices, such as
using a condom every time you have sex, lowers your
risk of ectopic pregnancy. This is because safe sex helps protect you from
sexually transmitted diseases (STDs) that can lead to
pelvic inflammatory disease (PID). PID is a common
cause of scar tissue in the fallopian tubes, which can cause ectopic
pregnancy.
You cannot prevent ectopic pregnancy, but you can
prevent life-threatening complications with early diagnosis and treatment. If
you have one or more risk factors for ectopic pregnancy, you and your health
professional can closely monitor your first weeks of a pregnancy.
Home Treatment
If you are at risk for having an ectopic pregnancy and you think you may be pregnant, use a
home pregnancy test. If it is positive, be sure to
have a confirmation test done by a health professional, especially if you are
concerned about developing an
ectopic pregnancy.
If you are receiving methotrexate treatment to end an ectopic pregnancy, you
may experience side effects from the medicine. See these
tips for managing methotrexate treatment for helpful suggestions on
minimizing these side effects.
If you experience an ectopic pregnancy loss,
no matter how early in a pregnancy, expect that you and your partner will need
time to grieve. It is also possible to develop
postpartum depression from the hormonal changes after
a pregnancy loss. If you experience
symptoms of depression that last for more than 2
weeks, it is important that you call your health professional or a
psychologist,
clinical social worker, or
licensed mental health counselor.
Contacting a support group, reading about the experiences of other women,
and talking to friends, a counselor, or a member of the clergy may help you and
your family deal with a pregnancy loss. For more information, see the Other
Places to Get Help section of this topic.
Concerns about future pregnancy
If you have had an
ectopic pregnancy, you may worry about your
chances of having a healthy or ectopic pregnancy in the future. Your risk factors and any fallopian tube damage you may have
will impact your future risk and your ability to become pregnant. Your health
professional can answer your questions based on your risk factors.
Medications
Medicine can only be used for early
ectopic pregnancies that have not ruptured. Depending
on where the ectopic growth is and what type of surgery would otherwise be
used, medicine may be less likely than surgical treatment to cause
fallopian tube damage.
Medicine is most
likely to work when an early ectopic pregnancy is not causing bleeding
and:
Your pregnancy hormone (hCG, or human chorionic
gonadotropin) level is low (less than 5,000).
It has been 6 weeks
or less since your last menstrual period.
The embryo has no heart
activity.
For an ectopic pregnancy that is more developed, surgery is
a safer and more dependable treatment.
Medication Choices
Methotrexate is used to stop the growth
of an early ectopic pregnancy. It can also be used after surgical ectopic
treatment to ensure that all ectopic cell growth has stopped.
Methotrexate treatment is
usually the first choice for ending an early ectopic pregnancy. If the
pregnancy is further along, surgery is safer and more likely to be effective
than medicine.
Regular follow-up blood tests are needed for days
to weeks after the medicine is injected.
Methotrexate can cause
unpleasant side effects, such as nausea, indigestion, and diarrhea. For
information about how to minimize side effects, see these
tips for managing methotrexate treatment.
Sudden abdominal pain
affects about 1 in 4 women who have the higher, more effective dose of
methotrexate. This may be related to the medicine itself or to the movement of
the pregnancy out of the fallopian tube.10
Methotrexate versus surgery
If your ectopic
pregnancy is not too far advanced and has not ruptured, methotrexate may be a
treatment option for you. Successful methotrexate treatment of an early ectopic
pregnancy avoids the risks of surgery, may be less likely to damage the
fallopian tube than surgery, and is more likely to preserve your fertility
after treatment.
If you are not concerned with preserving
fertility, surgery for an ectopic pregnancy is faster than methotrexate
treatment and will likely cause less bleeding.
Surgery
At any stage of development, surgical removal
of an ectopic growth and/or the
fallopian tube section where it has implanted is the
fastest treatment for
ectopic pregnancy. Surgery may be your only treatment
option if an ectopic pregnancy has gone past 6 weeks or if you have internal
bleeding. Whenever possible, surgery is done through a small incision using
laparoscopy. This type of surgery usually has a short
recovery period.
Surgery Choices
An ectopic pregnancy can be removed from a fallopian tube
by using salpingostomy or salpingectomy.
Salpingostomy. The ectopic growth is
removed through a small, lengthwise cut in the fallopian tube (linear
salpingostomy). The cut is left to close by itself or is stitched closed. This
surgery can be done when an embryo is smaller than
2 cm and is growing near the far end of the
fallopian tube.8
Salpingectomy. A fallopian tube segment
is removed. The remaining healthy fallopian tube may be reconnected.
Salpingectomy is needed when the fallopian tube is being stretched by the
pregnancy and may rupture or when it has already ruptured or is very damaged.
Both salpingostomy and salpingectomy can be done either
through a small incision using
laparoscopy or through a larger open abdominal
incision (laparotomy). Laparoscopic surgery has few risks and
heals more quickly than laparotomy.8 But for an
abdominal ectopic pregnancy or an emergency tubal ectopic removal, a laparotomy
is usually required.
What To Think About
When an ectopic pregnancy is
located in an unruptured
fallopian tube, every attempt is made to remove the
pregnancy without removing or damaging the tube.
Your future fertility and your
risk of having another ectopic pregnancy will be affected by your own
combination of
risk factors. These can include smoking, use of
assisted reproductive technology (ART) to get
pregnant, and how much fallopian tube damage you have.
As long
as you have one healthy fallopian tube, salpingostomy (small tubal slit) and
salpingectomy (part of a tube removed) have about the same effect on your
future fertility. But if your other tube is damaged, your doctor may try to do
a salpingostomy. This may improve your chances of getting pregnant in the
future.3
Other Treatment
Ectopic pregnancy is a potentially life-threatening condition that must be
treated with surgery, medicine, or frequent testing. Alternative treatments are
not appropriate for this condition.
Other Places To Get Help
Organizations
AMEND (Aiding Mothers and Fathers Experiencing Neonatal
Death)
4324 Berrywick Terrace
St. Louis, MO 63128
Phone:
(314) 487-7582
The Aiding Mothers and Fathers Experiencing Neonatal Death (AMEND)
organization offers support and encouragement to parents having a normal grief
reaction to the loss of a baby. It offers one-to-one peer counseling with
trained volunteers.
American College of Obstetricians and Gynecologists
(ACOG)
409 12th Street SW
P.O. Box 96920
Washington, DC 20090-6920
Phone:
(202) 638-5577
E-mail:
resources@acog.org
Web Address:
www.acog.org
American College of Obstetricians and Gynecologists
(ACOG) is a nonprofit organization of professionals who provide health care for
women, including teens. The ACOG Resource Center publishes manuals and patient
education materials. The Web publications section of the site has patient
education pamphlets on many women's health topics, including reproductive
health, breast-feeding, violence, and quitting smoking.
Planned Parenthood Federation of
America
434 West 33rd Street
New York, NY 10001
Phone:
1-800-230-PLAN (1-800-230-7526) (212) 541-7800
Fax:
(212) 245-1845
Web Address:
www.ppfa.org
The Planned Parenthood Federation of American provides
comprehensive reproductive health care and consumer information about family
planning, sexual health, and sexually transmitted diseases (STDs).
SHARE: Pregnancy and Infant Loss
Support
c/o St. Joseph's Health Center
300 First Capitol Drive
St. Charles, MO 63301-2893
Phone:
1-800-821-6819 (636) 947-6164
Fax:
(636) 947-7486
E-mail:
share@nationalshareoffice.com
Web Address:
www.nationalshareoffice.com
This organization provides mutual support for bereaved parents and
families who have suffered a loss due to miscarriage, stillbirth, or neonatal
death. SHARE provides newsletters, pen pals, and information regarding
professionals, caregivers, and pastoral care.
Speroff L, Fritz MA (2005). Ectopic pregnancy. In
Clinical Gynecologic Endocrinology and Infertility, 7th
ed., pp. 1275-1302. Philadelphia: Lippincott Williams and Wilkins.
Tay JI, et al. (2000). Ectopic pregnancy.
BMJ, 320(7239): 916-919.
Farquhar CM (2005). Ectopic pregnancy.
Lancet, 366: 583-591.
DeCherney AH (2002). Ectopic pregnancy and spontaneous
abortion. In DC Dale, DD Federman, eds., Scientific American Medicine, section 16, chap. 8. New York: WebMD.
American College of Obstetricians and Gynecologists
(1998). Medical management of tubal pregnancy. ACOG Practice Bulletin No. 3.
Obstetrics and Gynecology, 92(6): 1-7.
Brown WD, et al. (2002). Ectopic pregnancy after
cesarean hysterectomy. Obstetrics and Gynecology, 5(2):
933-934.
Hatcher RA, et al. (2004). Choosing among available
methods. In A Pocket Guide to Managing Contraception,
pp. 36-39. Tiger, GA: Bridging the Gap Foundation.
Cunningham FG, et al. (2005). Ectopic pregnancy. In
Williams Obstetrics, 22nd ed., pp. 253-272. New York:
McGraw-Hill.
Hajenius PJ, et al. (2006). Interventions for tubal
ectopic pregnancy. Cochrane Database of Systematic Reviews (1). Oxford: Update Software.
Barnhart KT, et al. (2003). The medical management of
ectopic pregnancy: A meta-analysis comparing "single dose" and "multidose"
regimens. Obstetrics and Gynecology, 101(4):
778-784.
Other Works Consulted
American Society for Reproductive Medicine (March
2001). Early Diagnosis and Management of Ectopic Pregnancy: A Practice Committee Report. Birmingham, AL: American Society for
Reproductive Medicine.
Credits
Author
Kathe Gallagher, MSW
Author
Ralph Poore
Editor
Kathleen M. Ariss, MS
Editor
Sydney Youngerman-Cole, RN, BSN, RNC
Associate Editor
Tracy Landauer
Associate Editor
Pat Truman, MATC
Primary Medical Reviewer
Joy Melnikow, MD, MPH - Family Medicine
Specialist Medical Reviewer
Liisa Honey, MD, FRCSC - Obstetrics and Gynecology
This information does not replace the advice of a doctor. Healthwise disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.
Speroff L, Fritz MA (2005). Ectopic pregnancy. In
Clinical Gynecologic Endocrinology and Infertility, 7th
ed., pp. 1275-1302. Philadelphia: Lippincott Williams and Wilkins.
Tay JI, et al. (2000). Ectopic pregnancy.
BMJ, 320(7239): 916-919.
Farquhar CM (2005). Ectopic pregnancy.
Lancet, 366: 583-591.
DeCherney AH (2002). Ectopic pregnancy and spontaneous
abortion. In DC Dale, DD Federman, eds., Scientific American Medicine, section 16, chap. 8. New York: WebMD.
American College of Obstetricians and Gynecologists
(1998). Medical management of tubal pregnancy. ACOG Practice Bulletin No. 3.
Obstetrics and Gynecology, 92(6): 1-7.
Brown WD, et al. (2002). Ectopic pregnancy after
cesarean hysterectomy. Obstetrics and Gynecology, 5(2):
933-934.
Hatcher RA, et al. (2004). Choosing among available
methods. In A Pocket Guide to Managing Contraception,
pp. 36-39. Tiger, GA: Bridging the Gap Foundation.
Cunningham FG, et al. (2005). Ectopic pregnancy. In
Williams Obstetrics, 22nd ed., pp. 253-272. New York:
McGraw-Hill.
Hajenius PJ, et al. (2006). Interventions for tubal
ectopic pregnancy. Cochrane Database of Systematic Reviews (1). Oxford: Update Software.
Barnhart KT, et al. (2003). The medical management of
ectopic pregnancy: A meta-analysis comparing "single dose" and "multidose"
regimens. Obstetrics and Gynecology, 101(4):
778-784.