Understanding Tubal Pregnancy and Ectopic hCG Levels
Human Chorionic Gonadotropin in Pregnancy
Human chorionic gonadotropin (hCG) is produced by an embryo once implantation has occurred. In a healthy pregnancy, the embryo implants in the uterus and the developing placenta causes hCG levels to rise. One to two weeks after conception (3-4 weeks of pregnancy, as dated from the last menstrual period), the hCG levels will be high enough to trigger a positive result on a home pregnancy test. According to the American Pregnancy Association, hCG levels will double every 48-72 hours during early pregnancy. They will typically peak between week eight and 11.
hCG levels can be monitored through a blood test. Quantitative beta hCG levels are determined every 48 hours to monitor pregnancies that are considered high risk. If the levels do not increase at the expected rate, the pregnancy is considered threatened. Slow rising hCG levels may indicate a non-viable intrauterine pregnancy, or may indicate an ectopic pregnancy has occurred. You can read this article that examines more insight and research into non-doubling hCG levels.
What Is an Ectopic Pregnancy?
When an egg is fertilized and implants in any location other than the uterus, the pregnancy is considered ectopic. "An ectopic pregnancy accounts for 1-2% of all pregnancies," says Dr. Tami Prince, an OBGYN at the Women's Health and Wellness Center of Georgia in Greensboro, Georgia. "They represent 2.7% of all pregnancy-related deaths according to the CDC and ACOG. 90% of ectopic pregnancies occur in the Fallopian tubes." Other times, a pregnancy may implant in the abdomen, in an ovary, or on the cervix—these cases are much rarer than a tubal pregnancy.
Spotting, cramping, and abdominal pain are often noted by the pregnant mother. If the pregnancy is far enough along, the ectopic pregnancy may be seen via a transvaginal ultrasound.
Can a baby survive an ectopic pregnancy?
When a pregnancy implants in a location outside the womb, the placenta cannot form normally and the hCG levels will not rise appropriately. The fetus does not get the necessary support it needs to develop. The embryo will rupture long before the fetus is viable.
What Does an Ectopic Pregnancy Feel Like?
According to New Kids-Center, here are some symptoms that you may feel if you are experiencing an ectopic pregnancy.
- A mild to severe pain on the side of your pelvis. This pain may appear suddenly or gradually.
- Vaginal bleeding that may seem different in color to menstrual bleeding. It may be more watery as well.
- Painful bowel movements or even diarrhea.
- Pain in your shoulder that increases when you lay down. This could possibly be internal bleeding that is irritating your organs.
- Fainting. This is related to internal bleeding.
- Heavy sweating.
- Shortness of breath and/or rapid heartbeat.
Do you want to know how quickly your hCG levels are increasing? Try this hCG calculator.
This calculator will determine your doubling time and compare it to the average.
Slow Rising hCG Levels
In some healthy pregnancies, the beta hCG level does not double every 48 hours. However, this is not necessarily a cause for concern. Many women have had low hCG levels and have gone on to have healthy pregnancies. According to Dr. Amos Grunebaum, an OBGYN at Cornell Weill Medical College, you should not put too much stock in having hCG levels determine the viability of a pregnancy. With that said, there should still be some monitoring. A drop in hCG levels ranging around 36% and more could indicate a miscarriage or ectopic pregnancy.
In addition, once hCG levels reach 6,000, the rate of increase begins to slow in all pregnancies. Late in the first trimester, hormone levels begin to plateau—the hCG level may even decrease a bit in the early part of the second trimester to a new, stable level that will be maintained until the pregnancy is complete.
Can a blood test detect an ectopic pregnancy?
A blood test merely gives a reading on hCG levels. A single quantitative hormone level is not useful for the diagnosis of an ectopic pregnancy. Serial measurements must be taken over time to determine how likely a pregnancy is to proceed.
Quantitative beta hCG levels are not diagnostic for an ectopic pregnancy. These levels are simply part of a larger clinical picture – the diagnosis of an ectopic pregnancy includes the evaluation of hCG levels in addition to ultrasonography and a physical exam. If the pregnancy can be visualized in a Fallopian tube (or elsewhere), the ectopic is confirmed. If the pregnancy cannot be visualized at all, the pregnancy might be ectopic, depending on the hCG levels. If the hCG levels are above 1,800 and the embryo cannot be visualized in the womb, the suspicion for an ectopic pregnancy increases dramatically.
Normal vs. Slow Rising hCG
Ultrasound Diagnosis of Ectopic Pregnancy
Tubal Pregnancy Diagnosis
Many women suspect a problem early in pregnancy, as spotting and cramping or abdominal pain are often present. In some tubal pregnancies, there are no early warning signs, and the first sign of trouble may be a ruptured Fallopian tube.
If spotting and cramping are observed, a woman should call her physician immediately. A workup will generally be ordered, including beta hCG levels and ultrasound examinations to determine the location and viability of the pregnancy. If the hormone levels are rising less than 66% over a 48 hour period, an ectopic pregnancy will be suspected.
If the hCG levels are low (less than 1,800), the pregnancy may not be visible on the ultrasound machine. In this case, a woman is often presented with a choice to wait and monitor the pregnancy until it can be observed, or to have a procedure called a Dilation and Curettage (D&C) to determine if there is any pregnancy tissue is in the womb. If there is no tissue in the womb, the pregnancy is determined to be ectopic. This method of determining the location of the failing pregnancy is not preferred, as there is a chance that there is an intrauterine pregnancy, and a D&C will end the pregnancy. If this method is used, and a pregnancy is not found in the womb, the ectopic pregnancy may be treated with methotrexate. Methotrexate is injected and is often successful at ending an ectopic pregnancy without surgery.
If the hormone levels are over 1,800 and the pregnancy can be visualized in a Fallopian tube, the diagnosis is certain and treatment will be scheduled immediately (by methotrexate injection if the pregnancy is in a very early stage, or by removal of the pregnancy and Fallopian tube).
How Long Does It Take for an Ectopic Pregnancy to Rupture?
According to Dr. Antonette Dulay, a perinatologist at Main Line Health in Philadelphia, Pennsylvania, an ectopic pregnancy can rupture anytime between six and 16 weeks. The bleeding after the rupture can be very severe and life-threatening. The longer it takes for a rupture to occur, the more at risk the mother is of a life-threatening occurrance.
Symptoms of an Ectopic Pregnancy
Treatment with Methotrexate
If a tubal pregnancy is an early stage, it may be treated medically (as opposed to surgically). Methotrexate is successful at treating tubal pregnancies when:
- beta hCG levels of 5,000 or less.
- No cardiac activity of the embryo is observed.
- The Fallopian tube is not ruptured or torn.
According to the University of Michigan, methotrexate works by preventing cell division and growth. The embryo breaks down and is passed from the Fallopian tube. If methotrexate is the chosen treatment option, hCG levels will be monitored on a regular basis until they have returned to 0.
"Methotrexate can be given as a single-dose regimen, two-dose regimen, and fixed multiple-dose regimen," says Dr. Prince. "The choice of regimen is guided by the initial hCG levels and discussions with the patient about the risks and benefits of the medication. There are similar success rates for both the single-dose and multiple-dose regimens. The latter is associated with an increased risk for adverse effects." According to Dr. Prince, these side effects include diarrhea, nausea, vomiting, dizziness, and stomatitis. "These side effects are directly related to the fact that methotrexate stops rapidly dividing cells in the body. This includes the linings of the stomach, bowel, and mouth."
According to Dr. Prince, here are some things that should be avoided during treatment.
- Sexual intercourse.
- Medications, foods, or vitamins that contain folic acid. Prenatal vitamins and folic acid supplements should be discontinued during treatment.
- Exposure to sunlight.
- Non-steroidal anti-inflammatory (NSAIDS) medications such as Ibuprofen, Aleve, or Advil as they may interfere with methotrexate.
- Medications and gas-producing foods that may either mask pain or be confused with worsening symptoms.
If the hormone levels begin to drop after the treatment is started, blood tests will be performed weekly until the hCG cannot be detected. This may take anywhere from 1-3 months to occur. "Two rounds of methotrexate are generally given before surgical intervention," says Dr. Prince.
Surgical Treatment for Ectopic Pregnancies
If medical treatment for an ectopic pregnancy fails, or if the tube ruptures or tears, surgical treatment will be required.
According to research from Dr. Vanitha Sivalingam, ectopic pregnancies are the leading cause of first trimester deaths in pregnant women. Between 1980 and 2007, there were 876 maternal deaths in the U.S. related to the condition. A ruptured ectopic pregnancy is a medical emergency and must be treated immediately to save the mother's life. An ultrasound examination will generally show a significant amount of "free fluid" in the abdomen, indicating internal bleeding due to the ruptured Fallopian tube. A salpingectomy (removal of the Fallopian tube) is generally performed to remove the pregnancy and to stop internal bleeding. In some cases, the pregnancy is removed without the removal of the entire Fallopian tube - this procedure is called a salpingostomy.
Both types of surgery may be performed through tiny incisions (laparascopic surgery), though they may sometimes require a larger incision (laparotomy).
hCG levels may be monitored by a physician until the hormone level falls to undetectable levels.
Fertility After Ectopic Pregnancy
If a Fallopian tube is removed via salpingectomy and the other tube is healthy, many women will be able to conceive again. According to the American Pregnancy Association, there is roughly a 60% chance of a successful pregnancy if the Fallopian tube has been left in place.
If, however, the other tube is also affected by scar tissue or other abnormalities, fertility will be significantly impacted. Fertility treatments such as in-vitro fertilization (IVF) may be required to conceive in this scenario.
After a woman has experienced a tubal pregnancy, however, she is at an increased risk for having another ectopic pregnancy. Approximately 10-15% of women with a prior ectopic pregnancy will experience another. For this reason, all future pregnancies must be monitored with beta hCG levels and early utlrasound examinations may be performed to verify the location of the embryo. You can read this personal account of a successful pregnancy following an ectopic pregnancy.
The Author's Experience with a Tubal Pregnancy
I was approximately 5 weeks pregnant and had frequent spotting, so beta hCG levels were ordered by my obstetrician. My first result showed a level of 1,411. Two days later, a repeat blood draw indicated the level had only risen to 1,629. Three days later (over a weekend), the levels rose to 2,100. While the levels were increasing, they were rising so slowly that the pregnancy was considered a failure. I was offered a D&C, but refused since we couldn't visualize the pregnancy via ultrasound. A few days later, I woke to severe pain and rushed to the emergency room - the pregnancy was ectopic and had ruptured. I was bleeding internally and my blood pressure was dropping. I had emergency surgery to remove the Fallopian tube and pregnancy. The physical recovery took approximately one week, and I was told my other tube was not scarred, which improves our chances for conceiving again.
- Dulay, A. T. Ectopic Pregnancy. From Merck Manual.
- Ectopic Pregnancy: Symptoms, Causes, Risks and Treatment. From American Pregnancy Association.
- Grunebaum, A. Normal hCG Levels In Early Pregnancy. From BabyMed.
- Human Chorionic Gonadotropin (HCG): The Pregnancy Hormone. From American Pregnancy Association.
- Methotrexate for Ectopic Pregnancy. From Michigan Medicine.
- Sivalingam, V. N., Duncan, W. C., Kirk, E., Shephard, L. A., & Horne, A. W. (2011). Diagnosis and management of ectopic pregnancy. The Journal of Family Planning and Reproductive Health Care / Faculty of Family Planning & Reproductive Health Care, Royal College of Obstetricians & Gynaecologists, 37(4), 231–240.
- What Does an Ectopic Pregnancy Feel Like? From New Kids-Center.
Tubal Pregnancy Treatment Poll
How was your ectopic pregnancy managed?
Questions & Answers
My hCG level was 843 on Wedsnesday morning. Two days later, it increased by only 1. On Sunday, it went up to 889. Since then, a few days have passed, and it is over 1500. I still have a pregnancy of unknown location, but wondering if I'm still at risk of an ectopic. They are doing more blood tests on Thursday. If it has doubled again, can it be an ectopic pregnancy?
The fact that your hCG doubled from the 23rd of September to the 25th of September is reassuring. It is interesting that your hCG did not double for a few days, but hopefully, your blood test will demonstrate an appropriate rise in level on Thursday. If your hCG continues to double, the chances of an ectopic pregnancy are greatly reduced, and your physician will continue to monitor until the pregnancy can be verified by ultrasound to be intra-uterine.Helpful 7
I received my methotrexate (MTX) shot on six days ago and my HCG was at 2160. After the shot it went up to 3200, which is odd. I was told this was normal three days later. My HCG today (twelfth day after the shot) is at 2979 and has dropped very little since my last test. Is it fine? I was not told about avoiding food rich in folate and have been having oranges and avocados. Could foods rich in folate slow down the drop in beta HCG levels?Helpful 1
I think I'm four weeks and three days pregnant, but my doctor says five weeks. My first hCG was 17; 48 hrs later it was 74; 96 hrs later it was 477. The doctor thinks ectopic; it’s doubling. I had an ultrasound and a visit yesterday. If it’s not at 1000 or higher he wants to give me the injection tomorrow, even without seeing if the baby is in the tube or not. My tubes were clear. I have a history of miscarriages, but I’ve never had an ectopic pregnancy. I’m 41 years old. What do you think?
Your hCG levels are doubling nicely. Since pregnancy dates are often off, I would be leery of ending a wanted pregnancy if they are not certain it is ectopic and cannot see anything in the tube. Does your doctor state why he thinks it is ectopic? With your hCG levels increasing nicely and nothing visualized in the tubes, I would be more inclined to watch (very carefully) and wait. I have had two ectopic pregnancies, and both had hCG levels that increased very slowly (never doubling). While the first one was never visualized, extra fluid could be seen in the ovarian area. I would, at the very least, seek a second opinion on the matter from a different physician. It is possible it is ectopic, and that is a life-threatening emergency, but since the hormone levels are doubling and there are no visual signs of an ectopic, a second opinion is warranted.Helpful 2
I had an ectopic pregnancy in June, 2018. I took six pregnancy tests in the month of August, 2018. Is it possible that I could be pregnant again? Are my HCG levels just slowly rising due to the methotrexate taken in June?
Did your physician monitor your hCG levels after your methotrexate treatment to verify they reached zero after your first ectopic pregnancy? If so, you are likely pregnant again. If your current hCG levels are rising very slowly, it is possible you have another ectopic pregnancy. Please see your physician as soon as possible to determine if your initial ectopic pregnancy never fully resolved or to determine if a second pregnancy has occurred.Helpful 1
Suspected heterotopic pregnancy. My HCG levels were: July 6 - 3300; July 11 - 5500; July 14 - 8900; and July 16 - 200. Can HCG drop that quickly?
That is a very rapid drop-off of HCG levels, and I would consult your physician with any questions about the blood test results. It is possible that the HCG level from an intra-uterine twin was causing the increase in HCG level, and may have become non-viable, causing a dramatic drop in HCG levels. That is a very large decrease in HCG to occur in 2 days, however, so I would ask your attending physician for the reason the level has dropped so dramatically. You may want to have the levels re-tested to rule out a laboratory error. Heterotopic pregnancies are extremely difficult and must be monitored very closely.Helpful 7