An ectopic pregnancy occurs when a fertilized egg attaches to the wall of the Fallopian tube instead of implanting in the uterus. If the fetus continues to grow in the Fallopian tube, it can cause irreversible damage to the tube and/or cause heavy bleeding in the pregnant woman.
Because of the serious complications that can arise with an ectopic pregnancy, any woman who is trying to conceive should be aware of the causes and symptoms of ectopic pregnancy so that she can seek help immediately if she thinks she might be experiencing an ectopic pregnancy.
Below is a list of 10 things you should know about ectopic pregnancy.
- How common is ectopic pregnancy?
- What are the risk factors for ectopic pregnancy?
- Ectopic pregnancy and hcg
- When will I know if I have an ectopic pregnancy?
- An ectopic pregnancy hurts
- Testing for Ectopic Pregnancy: What to Expect
- Would an Ectopic Pregnancy Show Up on a Home Pregnancy Test?
- Diagnosing Ectopic Pregnancy
- Positive Ectopic Pregnancy Tests: Now What?
- Deciding whether your symptoms are getting worse
- Rupture of Ovarian Pregnancy in a Woman with Low Beta-hCG Levels
- Symptoms of Ectopic Pregnancy
- Signs of Ectopic Pregnancy
- When to Seek Help
- Ectopic Pregnancy Diagnosis
- Using Ultrasound for Diagnosis
- A Ruptured Ectopic Pregnancy Presenting with a Negative Urine Pregnancy Test
How common is ectopic pregnancy?
Ectopic pregnancies are relatively uncommon. Only about 1 in 50 pregnancies are ectopic.
What are the risk factors for ectopic pregnancy?
- Because an ectopic pregnancy can occur if there is inflammation or scar tissue in the Fallopian tubes, a woman is at increased risk for an ectopic pregnancy if she has pelvic inflammatory disease and/or endometriosis. Pelvic inflammatory disease (PID) is most often caused by the presence of a sexually transmitted disease (although “normal” bacteria can sometimes cause PID), such as chlamydia or gonorrhea, and can cause inflammation in the Fallopian tubes. Endometriosis can cause scar tissue in or around the Fallopian tubes. When the Fallopian tubes are damaged for any reason, a fertilized egg might have trouble passing through, causing it to attach to the wall of the tube before it’s able to reach the uterus.
- Women who smoke are more likely to have an ectopic pregnancy. Women who have had surgery on their Fallopian tubes (for example, an unsuccessful tubal ligation or a tubal ligation reversal), are taking fertility drugs, or are undergoing in vitro fertilization have an increased risk for ectopic pregnancy. Also, some women are born with misshapen Fallopian tubes, which may place them at higher risk for ectopic pregnancy.
- If you have an intrauterine device (IUD) in place at the time of conception, you have a higher risk of ectopic pregnancy.
Ectopic pregnancy and hcg
An ectopic pregnancy will produce the pregnancy hormone hcg, so you will get a positive on a pregnancy test. A woman experiencing an ectopic pregnancy will most often experience the same early signs of pregnancy that occur with a “normal” pregnancy. But, unfortunately, an ectopic pregnancy cannot result in the birth of a healthy baby, and will always end prematurely.
When will I know if I have an ectopic pregnancy?
In most cases, an ectopic pregnancy will be discovered by the 8th week of pregnancy.
An ectopic pregnancy hurts
- An ectopic pregnancy causes sharp pelvic and/or stomach pain, which becomes more intense with strenuous movement. Other symptoms of an ectopic pregnancy are vaginal bleeding, and feeling dizzy, weak or nauseous. If you suspect that you are pregnant and are suffering from these symptoms, please see your health care provider immediately. It is important to know that the complications associated with ectopic pregnancy are severe and require medical attention.
- To determine if you are experiencing an ectopic pregnancy, a doctor will do one or all of the following:-A blood pregnancy test to check the level of pregnancy hormone circulating in your blood. If the test reveals a low level of the pregnancy hormone (hCG), this can indicate that there is a problem with the pregnancy and will warrant further investigation.-A pelvic exam to check the size of your uterus and feel for tenderness in your pelvic region-An ultrasound to verify the location of the implanted fetus
- The recommended treatment for ectopic pregnancy depends on how far along the pregnancy has advanced and whether or not the Fallopian tube has been stretched or has ruptured. If the ectopic pregnancy is discovered very early, medication (methotrexate) can be given to end the pregnancy, and can, hopefully, save the Fallopian tube. If the pregnancy is more than a few weeks along, it is likely that a woman will have to undergo emergency surgery to remove all or part of the impacted Fallopian tube.
- Having an ectopic pregnancy doesn’t mean that you won’t be able to become pregnant again in the future. However, if your Fallopian tube is damaged as a result of the ectopic pregnancy, it can be more difficult for you to conceive and for implantation to be successful. If you have ever had an ectopic pregnancy, it will be very important that you work closely with your health care provider when you decide to try to conceive in the future.
Unfortunately, there is no way to prevent an ectopic pregnancy. However, by being aware of the causes of ectopic pregnancy, you will know if you are at increased risk and can watch carefully for the signs that you are experiencing an ectopic pregnancy.
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Testing for Ectopic Pregnancy: What to Expect
A normal, healthy pregnancy develops in a woman’s uterus. But around 2% of the time, an embryo implants somewhere else – usually in the fallopian tubes, but sometimes in the ovaries, abdomen, cervix, or previous C-section scar. This is called an ectopic pregnancy.
Left untreated, ectopic pregnancies could cause ruptured fallopian tubes, internal bleeding, and maternal death, according to Dr. Mark D. Levie, professor of obstetrics & gynecology and women’s health at the Albert Einstein College of Medicine. With speedy diagnosis and treatment, however, a woman probably won’t have any complications. Here’s what you need to know about the tests used to diagnose an ectopic pregnancy.
- RELATED: Ectopic Pregnancy: Symptoms, Causes and Risk Factors
Would an Ectopic Pregnancy Show Up on a Home Pregnancy Test?
Since ectopic pregnancies still produce the hormone hCG, they’ll register as a positive home pregnancy test. Women with ectopic pregnancies will also experience early pregnancy symptoms like sore breasts, nausea, spotting, and more. The telltale symptoms (bleeding and abdominal pain) typically appear around 6-8 weeks, says Dr. Levie.
Diagnosing Ectopic Pregnancy
If you experience abdominal pain or bleeding during the first trimester, you should see a doctor to rule out ectopic pregnancy. This is especially important as an ectopic pregnancy progresses, which may cause lightheadedness, weakness, shoulder pain, fainting, and more. Getting a diagnosis early reduces the risk of complications like fallopian tube rupture and internal bleeding.
Confirming the Pregnancy
Many women visit their doctor for abdominal pain and bleeding without knowing the cause. If the doctor thinks you may be pregnant, he’ll test your blood or urine for human chorionic gonadotropin (hCG). Levels of hCG rise within 10 days of a missed period – although sometimes an increase can be detected earlier.
Your doctor might also conduct a pelvic exam. If he notices painful areas or a tender mass in the fallopian tube, he might suspect ectopic pregnancy. More testing is necessary to confirm the diagnosis. Pelvic exams could also rule out other causes of abdominal pain and vaginal bleeding.
- RELATED: Ectopic Pregnancy Pain, Explained
“We usually do an ultrasound to see if the pregnancy is in the uterus or outside the uterus,” says Tracy Anderson, M.D., a Kaiser Permanente Ob-Gyn based in Lakewood, Colorado. Doctors may use an abdominal ultrasound or transvaginal ultrasound (a device placed into the vagina that creates images through sound waves). However, Dr. Anderson notes that pregnancy in the fallopian tube might have inconclusive ultrasound results, leading to the next ectopic pregnancy test.
Quantitative hCG Test
Your healthcare provider may have already tested hCG levels to confirm a pregnancy. But according to Dr. Levie, he might also do a quantitative hCG test, which measures the exact level of hCG in the blood. “Usually during pregnancy, hormone levels increase every two days by 40%,” he says. “If this doesn’t happen, then it could signal an ectopic pregnancy.” What’s more, hCG levels tend to be lower overall in an ectopic pregnancy. You may need to test hCG levels over a few days for definite results.
Note that if ectopic pregnancy symptoms are severe (intense pain, heavy bleeding, etc.) the doctor may immediately treat the ectopic pregnancy. Waiting for a diagnosis could put the mother’s health at risk.
Positive Ectopic Pregnancy Tests: Now What?
If a doctor confirms ectopic pregnancy in the early stages, he will probably prescribe methotrexate to stop cell growth, says Dr. Anderson. But if the ectopic pregnancy is advanced or ruptured, surgery may be necessary to remove it.
Dr. Levie stresses the importance of early diagnosis of ectopic pregnancy. “Get to the doctor early in the pregnancy to confirm it’s in the right place,” he says, adding that most mothers are unlikely to suffer complications with proper treatment.
- RELATED: Ectopic Pregnancy Treatment: Do You Need Medication or Surgery?
- By Nicole Harris
The blood test that the doctors would perform is for Human Chorionic Gonadotrophin (hCG). This is a hormone produced in pregnancy. The hormone is most commonly detected in the urine by using a pregnancy test, where it can be positive or negative. Blood tests can tell you the exact value of the hCG level in the blood. Your GP can do this test but it will take a few days to get the result, the hospital and EPU will get the result in a couple of hours. This is why if you have symptoms and a surprisingly negative urine pregnancy test it is better to be seen at the hospital.
It is not uncommon in pregnancy to experience a period like ache in your lower tummy and back. The following however should be investigated:
- One-sided pain in your tummy which may be persistent or intermittent, which means it can come and go. The pain may have begun suddenly or gradually.
- A generalised discomfort with bloating and a feeling of fullness (not associated with eating) when lying down, particularly in women who have already had a child.
- Significant lower abdominal and/or back pain.
Shoulder tip pain
Shoulder tip pain
- The pain may have begun suddenly.
- Significant shoulder tip pain tends to develop with other symptoms such as feeling unwell, abdominal pain or vaginal bleeding, faintness, abdominal bloating and fullness, pain when opening your bowels.
It is caused by internal bleeding irritating the diaphragm (the muscle in your chest which helps you to breathe) when you breathe in and out. Shoulder tip pain is exactly where it says – not the neck or the back but the tip of your shoulder. If you look to the left over your shoulder and then cast your eyes down, the tip of your shoulder is where your shoulder ends and your arm starts.
Shoulders cause pain when we are stressed because we hold ourselves more rigidly and muscles in the back and neck go in to spasm or you may have slept in an awkward position – this is most likely not shoulder tip pain related to an ectopic pregnancy. Shoulder tip pain is very distinctive. You know when you have it because it is a very weird pain you have probably never experienced before.
Bladder or Bowel Problems
Bladder or Bowel Problems
- Pain when you have your bowels open (go for a poo)
- Pain when you pass water (have a wee)
- Shooting / sharp vaginal pain
Some pain and a change in your normal bladder and bowel pattern are features of a normal pregnancy for some women. All the same, if you present at your GP or Earmy Pregnancy Unit with such symptoms, it would be reasonable to have an early pregnancy assessment.
- Feeling light-headed or faint, or actually fainting
- Often accompanied by sickness and looking pale
- Increasing or slowing pulse rate or falling blood pressure may also be present
If you are experiencing these symptoms with or without shoulder tip pain present, seek urgent medical attention. This may be via an ambulance.
Deciding whether your symptoms are getting worse
It is difficult at times to know what symptoms are concerning. If you are at all worried, you should seek medical advice. Contact your GP or local Early Pregnancy Unit for advice. Your GP will likely refer you to your local Early Pregnancy Unit for an assessment.
This may involve a blood test in the first instance or an ultrasound scan dependent on how many weeks pregnant you are and your symptoms.
It is important to remember that pregnancy symptoms are very common, and that not all women experiencing such symptoms have ectopic pregnancy as it is rare (incidence 1.14% in the UK). However, it is important to be vigilant and if in doubt, seek medical attention/advice.
Rupture of Ovarian Pregnancy in a Woman with Low Beta-hCG Levels
Background. Ovarian pregnancy is a rare form of ectopic pregnancy. It is often difficult to distinguish from tubal pregnancy, and diagnosis and management are frequently a challenge. Case. A 33-year-old nulligravida woman presented with light vaginal bleeding and bilateral lower quadrants abdominal pain. Beta-human chorionic gonadotropin (beta-hCG) level (592 mUI/mL) and clinical and ultrasound (US) findings were suspicious for tubal pregnancy. On the third day, despite beta-hCG decrease (364 mUI/mL), she complained of severe pain in the lower abdomen, and physical examination revealed abdominal rebound tenderness. US showed a large amount of fluid in the abdominal cavity. Because of the unstable clinical condition, emergency laparoscopy and resection of left ovarian ectopic pregnancy were performed. Histology confirmed ovarian gestation. Conclusion. This case shows that ectopic pregnancy rupture may occur despite low levels of beta-hCG. Hemoperitoneum is not contraindication to laparoscopy.
Ovarian pregnancy is one of the rarest variants of ectopic implantation, and incidence is estimated to be 3% of diagnosed ectopic pregnancies . The diagnosis of ovarian pregnancy is difficult. We report a case of ruptured ovarian pregnancy misdiagnosed as tubal pregnancy, which caused significant hemoperitoneum and was successfully treated by conservative laparoscopy.
2. Case Presentation
A 33-year-old nulliparous woman presented to the gynecologic emergency room of our Department complaining of light vaginal bleeding and bilateral lower quadrants abdominal pain without signs and symptoms of circulatory instability. She reported a history of 5 weeks of amenorrhea, and her previous menstrual cycles were regular. She had no history of sexually transmitted disease or pelvic inflammatory disease, nor previous gynecological surgery. Physical examination revealed initial blood pressure 110/70 mmHg, pulse 80 beats/min, and body temperature 37.5°C. On speculum examination there was a small amount of blood in the vagina but the cervical os was closed. On bimanual clinical examination she was found to have a normal size of anteverted uterus and no cervical motion tenderness. The left adnexa was tender to palpation but no adnexal mass was appreciated. Urine pregnancy test was positive, and the serum beta-chorionic gonadotropin (beta-hCG) level was 592 mUI/mL. Transvaginal ultrasound (US) examination showed an empty uterus, corpus luteum in the left ovary and a 25 mm hyperechoic mass with a central hypoechoic shadow in the left adnexa, suggestive of a tubal pregnancy (Figure 1). A structure simulating yolk sac or fetal pole was not found. The right adnexa was normal, and there was no sign of free fluid in the abdominal cavity. Her initial laboratory results were: White Blood Cells (WBC): 4.6 × 109/L, Hemoglobin (Hb): 12 g/dL, Hematocrit (Hct): 34%, Platelets (Plt): 216 × 109/L, and Red Blood Cells (RBC): 4.2 × 1012/L. The patient was admitted to the Gynecological ward with a diagnosis of suspected tubal pregnancy. Daily routine blood examinations, including serum beta-hCG, and US were performed showing that the patient was in a stable clinical condition.
Transvaginal gray-scale US image of left adnexa reveals a 25 mm hyperechoic mass with a central hypoechoic shadow, suggestive of a tubal pregnancy. ES: ectopic sac; CL: corpus luteum.
On the third day of hospitalization, despite a beta-hCG decrease to 364 mIU/mL, the patient complained of severe pain in the lower abdomen, and there was abdominal rebound tenderness during physical examination. The patient’s pulse rate was 90/min, and blood pressure 95/60 mmHg. Hb levels dropped to 8.5 g/dL, the number of erythrocytes reduced to 3.17 × 1012/L, and Hct to 23.5%. Transvaginal US showed a large amount of fluid in the cul-de-sac and abdominal cavity. The patient was taken to the operating room with a presumptive diagnosis of a ruptured ectopic pregnancy and hemoperitoneum. Emergency laparoscopy was performed. During laparoscopy, 600 mL of fresh blood along with dark blood clots were evacuated from the abdominal cavity. The left fallopian tube appeared to be normal. Active bleeding was observed from the left ovary, where a hemorrhagic mass suggestive of ruptured ectopic pregnancy (5 cm × 4.5 cm × 3.5 cm) was present. The gestational sac was easily shelled out of the encasing ovarian tissue (Figure 2). Pathologic analysis confirmed a left ovarian gestation with presence of necrotic chorionic villi and a corpus luteum within the ovarian tissue. After laparoscopy, hemoglobin value was 8.1 g/dL, and no blood transfusion was needed. The patient had an uneventful postoperative course and was discharged two days later.
(c) Figure 2
The laparoscopic treatment of the ovarian pregnancy: (a) at the beginning of the procedure: normal aspect of the uterus (u) and left fallopian tube (t), ruptured ectopic pregnancy in the left ovary (e); (b) gestational sac shelled out of the encasing ovarian tissue; (c) appearance of the left ovary after removal of ectopic pregnancy.
Ovarian pregnancy is a rare variant of ectopic pregnancy. Early diagnosis of ovarian pregnancy is necessary in order to avoid more serious complications and emergency invasive procedures . However, preoperative diagnosis remains challenging, and it is diagnosed generally during surgery . Correct diagnosis of ectopic pregnancy can often be made on the basis of patient history, signs and symptoms, serum beta-hCG levels, and pelvic US examination. In our case the ovarian pregnancy was misdiagnosed as a tubal pregnancy, as US was not useful for distinguishing between ovarian and tubal pregnancy. Low beta-hCG levels may be misleading, and tubal ruptures have been reported in cases with decreasing beta-hCG . An accurate differential diagnosis is important in ectopic pregnancies as patient management often differs depending on the type and the exact location of the pregnancy . Medical therapy with methotrexate was not a possible option due to the occurrence of massive bleeding. Generally, in case of hemoperitoneum most surgeons prefer to perform laparotomy. Few cases of laparoscopic treatment in women with hemoperitoneum have been reported . In our case the ovarian pregnancy was easily removed laparoscopically after evacuation of blood from the abdominal cavity. This conservative technique allowed preservation of the ovary and reproductive capability.
In conclusion, ovarian pregnancy is a rare event that is difficult to detect, and a quantitative beta-hCG level may be an unreliable predictor of ectopic pregnancy evolution. Hemoperitoneum is not always a contraindication to laparoscopy.
Symptoms of Ectopic Pregnancy
Abdominal pain and abnormal bleeding may be symptoms of an ectopic pregnancy.
The initial symptoms of an ectopic pregnancy are the same as those of a normally progressing pregnancy:
- Missed period
- Nausea and occasional vomiting
- Breast tenderness
Signs of Ectopic Pregnancy
If the pregnancy is in the fallopian tube, as most are, the following sign and symptoms develop as the growing embryo presses against the inflexible walls of the fallopian tube:
- Sharp, stabbing pain in the pelvis, abdomen, and possibly shoulder and neck. The pain may come and go and may vary in intensity.
- Vaginal bleeding
- Dizziness and light-headedness
Ectopic pregnancies that are not in the fallopian tube (such as an abdominal pregnancy) may cause more generalized abdominal pain.
When to Seek Help
An ectopic pregnancy can be life-threatening, so it’s important to seek medical help if you notice any of the symptoms of an ectopic pregnancy.
Any type of ectopic pregnancy can cause heavy internal bleeding. An ectopic pregnancy located in the fallopian tube can rupture the tube, affecting future fertility.
Virtually all ectopic pregnancies are not viable, meaning they cannot result in a healthy baby, and need to be ended to protect the health of the pregnant woman.
Ectopic Pregnancy Diagnosis
When an ectopic pregnancy is suspected, the first step may be to do a pregnancy test, or qualitative hCG test, if the woman has not already had a positive pregnancy test.
A qualitative hCG detects human chorionic gonadotropin (hCG) in the mother’s urine or blood. The hormone is produced in the placenta starting shortly after implantation of the fertilized egg.
A pregnancy test can detect hCG levels within 10 days of a missed period, and some tests can detect it even earlier, within a week of conception.
A negative pregnancy test does not absolutely rule out pregnancy or ectopic pregnancy; it may simply be too early to detect hCG in the mother’s urine or blood.
A doctor may also order one or more quantitative hCG tests to help diagnose (or rule out) an ectopic pregnancy. A quantitative hCG test measures the level of hCG in the blood.
In an ectopic pregnancy, the blood level of hCG is usually lower than in a normally developing pregnancy and also rises at a slower-than-normal rate.
Using Ultrasound for Diagnosis
Another step in diagnosing a suspected ectopic pregnancy is using ultrasound to locate the implanted embryo.
Sometimes a transvaginal ultrasound, in which a thin probe is introduced into the vagina and sound waves are used to create images of internal structures, is performed.
If an embryo is located outside the uterus, a treatment plan is made based on the mother’s overall health, where the embryo is located, and the mother’s hCG levels (a falling level can indicate that the pregnancy is resolving on its own).
If an embryo is not located, doctors continue to monitor the pregnancy until a diagnosis can be made.
In some cases the diagnosis will be confirmed by inserting a laparoscope — a very small viewing instrument — into the abdomen through a small incision below the navel.
If during the scan a pregnancy – that is a gestation (pregnancy) sac, a foetal pole and a beating heart – can be seen in the uterus, the chance of a coexisting ectopic pregnancy, whilst possible, is unlikely. In a case like this, bleeding may be implantation bleed, bleeding during a healthy pregnancy, or due to an impending miscarriage. Pain may be caused by a normal, healthy corpus luteum cyst, which forms on the ovary after ovulation, swelling to cause pain. Changes to the bowel and bladder may be attributed to hormonal changes, causing the woman to want to pass urine (wee) more often and possibly even be a little constipated (find it hard to open the bowels to have a poo).
If signs of pregnancy can be seen in the uterus, usually a yolk sac but either no embryo or if the embryo is too small to expect to see a heartbeat, this situation is given the medical label of an ‘Intrauterine Pregnancy of Uncertain Viability’ or PUV or IPUV. In this circumstance, you should be offered a repeat scan a week to ten days later to check whether the baby has developed a heartbeat.
This is an emotionally difficult time as it is not clear whether the dates for conceiving were wrong or whether the lady is likely to miscarry. Blood tests will also typically be taken to establish the level of hCG in the blood stream and again 48 hours later, to see how the levels are behaving.
If no pregnancy can be seen in the uterus, or there is a small gestation sac in the uterus without a yolk sac or embryo, the pregnancy will be medically labelled as a Pregnancy of Unknown Location or PUL. It is important to understand that PUL is not a diagnosis; it is a label given until the final location of the pregnancy can be identified with certainty. In the event of a PUL, blood will be taken to measure serum progesterone and hCG and the hCG test repeated 48 hours later. The doctors would also want to repeat the scan.
Until the location of the pregnancy is known definitively or the serum hormone levels have decreased to below pregnancy levels, there is a risk of complications associated with an as yet undiagnosed ectopic pregnancy. For every 100 pregnancies labelled as a PUL about 10 will subsequently be found to be ectopic; and not all of these will need treatment.
If no pregnancy can be seen in the uterus but there is evidence of free fluid in your abdomen and or a possible ‘mass’ in the approximate location of one of your fallopian tubes, the doctor would then be likely to diagnose a possible ectopic pregnancy. An initial scan will detect over 70% of ectopic pregnancies.
A Ruptured Ectopic Pregnancy Presenting with a Negative Urine Pregnancy Test
A negative urine pregnancy test in the emergency department traditionally excludes the diagnosis of pregnancy. We report a rare case of ruptured ectopic pregnancy in a patient with a negative urine pregnancy test but with a serum beta-human chorionic gonadotropin (β-hCG) of 10 mIU/mL. The patient developed hemoperitoneum and required laparoscopy by Obstetrics and Gynecology (OB/Gyn). This case highlights the fallibility of the urine pregnancy test in diagnosing early pregnancy.
Ectopic pregnancy remains a leading cause of death in women of childbearing age in the United States . Women at highest risk include those less than 25 years of age and of nonwhite ethnicity . In the emergency department (ED), the prompt identification of a pregnant woman with an ectopic pregnancy is critical because the sudden rupture of a fallopian tube can lead to hemorrhagic shock . In addition, early diagnosis may allow for nonoperative intervention and preservation of fertility. The classic triad for an ectopic pregnancy of abdominal pain, amenorrhea, and vaginal bleeding is only present in about 50% of women with this condition.
A 35-year-old woman with a past medical history of bipolar affective disorder, anxiety, hemorrhoids, and polysubstance abuse presented to the ED with the chief complaint of rectal discomfort. She had two days of diffuse abdominal pain radiating to the lower back, dyspareunia, dyschezia, and nausea without vomiting. She denied urinary complaints, vaginal discharge, or bleeding. Her last menstrual period was four weeks before.
Her physical exam—including pelvic, rectal, and abdominal exam—was unremarkable, and her vital signs were stable. Urinalysis, complete blood count (CBC), basic metabolic panel (BMP), and a vaginal wet prep were all within normal limits. Her urine pregnancy test was “weakly positive” and her serum β-hCG was 23 mIU/mL. A pelvic ultrasound showed no evidence of a gestational sac and was otherwise unremarkable. She was diagnosed with early pregnancy and constipation and referred for serial β-hCG measurements and repeat pelvic imaging.
She returned to our ED three days later with complaints of worsening abdominal pain, increasing nausea, and dysuria. She denied vaginal bleeding. Physical exam revealed stable vitals, severe diffuse abdominal pain with guarding, cervical motion tenderness, and bilateral adnexal tenderness without palpable masses. Her urine pregnancy test was negative but her serum β-hCG was 10 mIU/mL. Her hemoglobin had dropped from 13.2 g/dL three days earlier to 10.8 g/dL. Figure 1 shows the repeat pelvic ultrasound images, demonstrating a large complex fluid collection in the pelvic cul-de-sac, possibly representing a hemorrhage without evidence of an intrauterine pregnancy. OB/Gyn emergently took the patient to the operating room for laparoscopy where she was diagnosed with hemoperitoneum and ruptured ectopic pregnancy. Gestational tissue was identified during the surgery. Her postoperative recovery was unremarkable.
Figure 1 Transverse and longitudinal ultrasound images of the uterus showing intra-abdominal hemorrhage and no intrauterine pregnancy.
Diagnosing a ruptured ectopic pregnancy with a negative urine pregnancy test is exceptionally rare and only a few cases have been reported in the literature . The following list summarizes reported cases of ectopic pregnancies with negative urine pregnancy tests.
In a normal intrauterine pregnancy, trophoblasts will secrete β-hCG with blood levels reaching 50–300 mIU/mL within two weeks of fertilization . The urine pregnancy test will generally become positive when the serum β-hCG is greater than or equal to 25 mIU/mL . In a normal early intrauterine pregnancy, the β-hCG level doubles approximately every 48–72 hours until about 60–90 days after conception . Only 15% of women with ectopic pregnancies will have serum β-hCG levels that rise in a way similar to normal intrauterine pregnancies . The most likely mechanism for low β-hCG levels in ectopic pregnancy is the degeneration of trophoblasts that result in cessation of β-hCG production . Other causes can include a small number of chorionic villi present to produce β-hCG, abnormal β-hCG synthesis, or an enhanced β-hCG clearance . A woman with an aborted pregnancy will have her β-hCG levels decreasing by approximately one-half in 48 hours and going to zero within several days .
Clinicians should not use the β-hCG level to determine the need for an ultrasound if a pregnant female has symptoms that may be consistent with an ectopic pregnancy. In one study, approximately 25% of pregnant women in the ED presenting with abdominal pain and/or vaginal bleeding were diagnosed with an ectopic pregnancy and a β-hCG less than 1500 mIU/mL, which has been the traditional β-hCG level at which an intrauterine pregnancy can be seen on ultrasound . In a retrospective study of ectopic pregnancies, the authors found that 25% of patients had a β-hCG level less than 1000 mIU/mL, yet a pelvic ultrasound suspicious for ectopic pregnancy . Our case illustrates the ongoing clinical diagnostic challenges associated with ectopic pregnancy. In the correct clinical setting, it is of importance not to exclude this potentially life-threatening diagnosis with a negative urine pregnancy test.
The authors declare that they have no competing interests.
The authors thank Megan Christopher for editorial support.