Table of Contents
- 1 All about hCG Levels
- 1.1 What does the hCG levels mean?
- 1.2 What is a normal hCG level for 6 weeks pregnant?
- 1.3 What does IU l mean in pregnancy?
- 1.4 What are the hCG levels for twins?
- 1.5 How long does it take for hCG to rise?
- 1.6 What should your hCG levels be at 5 weeks pregnant?
- 1.7 What does it mean hCG intact?
All about hCG Levels
Human chorionic gonadotrophin or hCG is a hormone that is produced by the placenta during pregnancy. hCG levels are usually detected via blood or urine tests. Apart from identifying whether pregnancy has occurred or not, hCG levels also help in checking how well pregnancy is progressing at every stage. It also informs about the development of baby. It is a biochemical created initially by the fertilized egg; its production is started soon after the egg travels down the fallopian tube and then to the uterus prior to implantation. Once implantation occurs and pregnancy happens, the placenta is formed and the creation of hCG hormone becomes its responsibility.
hCG Levels During Pregnancy
(in weeks since last menstrual period (LMP))
|3 Weeks LMP||5-50 mIU/ml|
|4 weeks LMP||5 -426 mIU/ml|
|5 weeks LMP||18 – 7,340 mIU/ml|
|6 weeks LMP||1,080 – 56,500 mIU/ml|
|7 – 8 weeks LMP||7,650 – 229,000 mIU/ml|
|9 – 12 weeks LMP||25,700 – 288,000 mIU/ml|
|13 – 16 weeks LMP||13,300 – 254,000 mIU/ml|
|17 – 24 weeks LMP||4,060 – 165,400 mIU/ml|
|25 – 40 weeks LMP||3,640 – 117,000 mIU/ml|
Many women resort to hCG levels calculator that is easily available online on a number of websites. There are numerous at-home tests also available that are quick enough to detect hCG levels after implantation as well. However, it is recommended to confirm pregnancy and follow-up progress through recognized laboratory testing. Almost all of the pregnancy tests available in the market and also those conducted at the laboratories detect pregnancy through evaluating the levels of hCG hormone. The level of hCG hormone is quite critical in determining the status and health of pregnancy and it is important to understand it in great detail.
What does the hCG levels mean?
Even before a female misses her period, her body starts producing hCG hormone and its concentration intensifies on a daily basis as pregnancy progresses. It is possible to detect hCG hormone’s presence in the bloodstream only after 11 days of conception since urine starts excreting hCG. It is produced by the developing embryo inside the uterus and hence, only pregnant ladies produce hCG hormone. Sometimes it is also referred to as pregnancy hormone.
hCG levels basically mean the increment in volume of the hormone. As noted above, hCG hormone keeps increasing on a daily basis and after a lot of research medical specialists have managed to evaluate the reasonable and ideal rate of increment of this hormone that would determine healthy and unhealthy status of pregnancy.
To confirm pregnancy, it is important that hCG levels are above 25 mlU/ml. and any reading that is below or less than 5 mlU/ml would mean that the woman has normal hCG levels not pregnant and the test result will be negative. hCG concentration in the body is measured in milli-international units per milliliter of the blood of the expecting mother.
It’s measurable increment over time is very crucial for the progressing of pregnancy while individual readings don’t matter. Steady and expected rise in hCG levels early on means that the placenta is secreting enough hCG to support and maintain the embryo (also called zygote).
Typically, hCG levels get doubled after every three days and it reaches the peak level by the 11th week of pregnancy. Afterward, it starts declining and remains low for the remaining pregnancy term.
Low and High hCG Levels:
Low levels of hCG can indicate various things such as:
- Miscalculated pregnancy date
- Blighted ovum
- Probable miscarriage
- Ectopic pregnancy
In the same way, high hCG levels also mean different things such as:
- Miscalculated pregnancy dating
- Molar pregnancy
- Multiple pregnancies (Twins, Triplets, Quadruplets, etc.)
It is suggested that hCG levels are rechecked after 48-72hours again to assess the rise or fall in the hormone level. hCG levels aren’t regularly checked but if the mother is experiencing cramping, bleeding or has a history of miscarriages then it is important to monitor hCG levels rise.
What is a normal hCG level for 6 weeks pregnant?
During pregnancy, it is quite normal to get worried at every single twitch and even an unfavorable test result can make expecting moms restless. It is however not out of the ordinary that hCG levels vary enormously on a daily basis and from person to person. Even every pregnancy of a female is different from the previous one.
What is important to note is that the placenta starts secreting hCG merely days after the embryo implants itself into the uterine wall. Initially the hCG levels will be low and it will only show into your system after a week or so. However, within no time it will start doubling after every 30 hours. The rise in hCG hormone reaches its peak between 7-12 weeks starting from the last menstrual period (LMP), after which it begins to decline. During six weeks’ time the idea or predictable level of hCG is between 1,080 to 56,500 mIU/ml.
This increase is rather predictable but according to experts, there is a massive variation in hCG levels even on the very first day of missed period. Some women have 0 mIU/ml, which means their hCG level is non-measurable. Conversely, some have above 400 mIU/ml reading. This means it is perfectly normal for hCG levels to fluctuate in the initial phase of pregnancy. In the same manner, hCG levels miscarriage are drastically low and after observing constant decline, doctors are able to diagnose that the pregnancy is not progressing in a healthy manner.
Therefore, if you are 6 weeks pregnant and your test report shows hCG levels that fall outside of the predicted readings then there is nothing to worry about. In a majority of the cases the pregnancy progresses normally and the levels rise after some time.
What does IU l mean in pregnancy?
IU/L refers to International units per liter. Generally, there are two kinds of hCG tests namely a qualitative test that detects whether hCG is present in the blood or not and quantitative test that measures the exact amount present in the blood. Regardless of the test, the specimen taken as sample is measured as IU/L.
When the health care practitioner feels that the pregnancy is not progressing as expected or it is not viable due to abnormally low or high hCG readings then a quantitative hCG blood test is required. Otherwise, a qualitative test works just fine. If the pregnancy is progressing normally, the hCG hormone will keep increasing at a steady rate starting after 11 days of conception. You will notice that 2 weeks pregnant hCG levels are much higher than the first week levels. Usually, a urine test taken after 12-14 days of conception can detect pregnancy quite reliably. This means hCG levels reach a substantial rise at two weeks pregnancy.
Just like there are two types of blood tests for detecting pregnancy, there are also two types of specimen that can be provided for this purpose. These are Blood pregnancy tests and urine tests. Blood pregnancy tests are also known as serum tests. These can detect the hCG at very low levels in comparison to urine tests as these can detect levels as low as 2-5 IU/L. Comparatively, urine pregnancy tests can detect hCG when the hormone reaches 100 IU/L while the average range of detection by urine tests falls between 25-250 IU/L.
Blood pregnancy tests are not ordered normally and urine tests are mostly preferred. A health practitioner orders blood test only when there is serious medical reason such as to assess hCG levels ectopic pregnancy, that is, when the doctor suspects that the female is having ectopic pregnancy. Otherwise, blood pregnancy tests are not part of routine testing. It must be noted that levels that fall between 5-25 IU/L are deemed inconclusive and levels below 5 IU/L means there is no pregnancy.
What are the hCG levels for twins?
If the mother carries twins then hCG levels twins will be naturally higher than those of a woman carrying a single baby. However, carrying twins cannot be taken as a guarantee for higher hCG levels. There is a huge different otherwise between singleton and twin pregnancy hCG levels and these levels also vary from mother to mother as well as pregnancy to pregnancy.
Women who are having twins or multiple embryos will observe at least 30-35% higher hCG levels than singleton pregnancy. This doesn’t mean that hCG levels twins will start doubling from day one; the elevation will be as gradual as it is in singleton pregnancy and hCG will not be detected before first day of missed period. It must be noted that although many pregnancy ladies want their hCG levels to increase rapidly but according to health experts very rapid increment in this hormone is also a cause of concern. It could be caused by another issue such as rapid growth of placenta tissue instead of the embryo or when the embryo has implanted itself in the ovary. hCG’s concentration is also impacted by some rare types of cancers.
Nonetheless, since developing embryo starts producing hCG, therefore, the level of this hormone in a woman’s body would be particularly high if she is carrying twins, triplets, quadruplets or higher order multiples. hCG comes purely from the developing embryo and not from the body so if there are two embryos, each developing baby will secrete the normal range of hCG as expected but the cumulative concentration of this hormone will be higher when tested.
So, hCG levels although differ drastically between females but these are generally higher in twin pregnancies and the rate will keep on increasing as the pregnancy progresses. As is the case with single pregnancies, with twins too the hCG levels will increase significantly throughout the first three months. The levels will double after 48-72 hours just like it does in singleton pregnancies. One important point to be noted is that since females carrying twins have higher amount of hCG in their urine and blood therefore, they can expect to get a positive pregnancy test much sooner than those carrying single babies.
There is a downside though; females carrying twins will experience more hCG related issues than others. Such as they might experience severe form of morning sickness than those carrying singles because hCG contributes to morning sickness so the higher the level the greater will be the severity.
How long does it take for hCG to rise?
After conception, the developing placenta produces hCG hormone and it takes around two weeks for hCG levels to be high enough to be detected in the urine by either a laboratory test or a home pregnancy test. Therefore, if a woman tests for pregnancy on the very first day of missed period and it gives negative result then it would be appropriate to check the next day if period is still missed. If even after a week there is no sign of period then it is better to get the test done from a laboratory or a clinic because from gestational point of view the women must already be 4 weeks pregnant, and a blood pregnancy test will accurately detect hCG levels at 4 weeks.
Usually, pregnant women are asked to remain careful while studying their hCG levels and never worry too much about the rise of hormone level. That’s because every woman has different kind of pregnancy and the hCG levels will rise at different rates. The rule of thumb is that any rate that is lower than 5mlU/ml means not pregnant and if the levels are 25 mlU/ml or above then there is pregnancy.
At three weeks pregnant, a woman’s hCG levels will fall between 5-50mlU/ml. In early pregnancy the rise in hCG hormone will be quite rapid and later in pregnancy it will slowly decline. The point to remember is that every female’s hCG levels will increase at a different rate and will greatly vary so doctors usually don’t monitor the levels too much except if there is bleeding or pain. When the hCG levels reach 1000-2000 mlU/ml then the doctor will conduct a transvaginal ultrasound to view the formation of gestational sac inside the pregnant female’s body.
There is also a possibility that hCG levels stop rising, which basically indicates that the pregnancy is ectopic or a miscarriage has occurred or is occurring. Similarly, if hCG levels are too high, then it indicates presence of multiple embryos. Other than that, there aren’t any environmental or exterior factors that might affect the hCG levels rise or fall. Furthermore, medications like pain relievers, antibiotics, herbal supplements etc., cannot alter hCG levels and also won’t affect the results of a pregnancy test.
What should your hCG levels be at 5 weeks pregnant?
As already mentioned, normally hCG levels doubles after every 48-72 hours and the rate of increase is approximately 60% after two days. Five weeks pregnant hCG levels will reach 100-10,000 mIU/ml and after 7 weeks it reaches 6,000 mIU/ml. Generally, health practitioners wait until 6-7 weeks to detect the health of pregnancy by assessing the fetal heartbeat.
The levels of hCG rise steadily during the first ten weeks and double after every 1.4-3.5 days’ time especially between week 4 and week 6. More than 6,000 mIU/ml hCG levels will double in four or more days and generally a level of 7200 mIU/ml indicates that the yolk sac has been formed and can be viewed by an ultrasound. After 6-7 weeks, the hCG levels reach 10,800 mIU/ml approximately and this is the time when the ultrasound will detect the heartbeat of the fetus.
Typically, by fifth week of pregnancy females already know that they have become pregnant. If a blood or urine test does not give accurate result at this stage then it is suggested to repeat the test after 2 to 4 days and the result should be compared with the previous levels.
Usually, at five weeks pregnant, hCG levels may or may not be high enough to be detected by home pregnancy tests as the rate of hormonal rise vary from woman to woman. It is almost impossible to predict the exact day and time of ovulation without professional help and regular ultrasounds. This is why there is always a lot of confusion surrounding hCG levels. Many times we believe that a lot of time has passed and start obsessing over low hCG count while pregnancy has taken place only few days back and this is why the rate of rise is low. On the other hand, with the progress of pregnancy, the rapid increase in the levels will slow down to a great extent. However, blood hCG levels are not credible enough to declare a pregnancy as viable or unviable.
What does it mean hCG intact?
HCG hormone has much more to it than we are aware of. We usually consider it as a single molecule while in reality there are various variants of this hormone. Intact hCG is one of the variant of hCG molecule. It is actually the biologically active form of hCG hormone, which is produced by the placenta. The job of Intact hCG is to not only generate but also retain higher concentrations of blood progesterone inside the woman’s body. It is worth noting that high levels of blood progesterone are vital for the pregnancy to progress healthily. Progesterone levels are in fact crucial for maintaining the pregnancy.
Intact hCG is made up of two distinct protein subunits. These subunits are called alpha and beta. Alpha subunit is not that different from hCG because it is part of the three other hormones (which also are completely different from hCG) called thyroid stimulating hormone, follicle stimulating hormone and luteinizing hormone. The three hormones have their own beta subunit as well.
On the other hand, the beta subunit is quite unique to hCG. Free Alpha Subunit of hCG (hCGα) is the alpha unit that has no biological activity and it cannot keep blood progesterone levels high enough to maintain pregnancy. Free Beta Subunit of hCG (hCGβ) is the variant of hCG that also lacks biological activity and overall its concentration in the blood during pregnancy is about 1%.
Full Intact hCG molecule is created when the alpha and beta subunits are linked to each other. When pregnancy occurs a majority of the hCG molecule present in the blood stream is Intact hCG. When the hCG hormone loses its biological activity and the alpha and beta subunits come apart, then Nicked hCG is made. It is created from a chemical bond that gets broken in the beta subunit. During pregnancy Nicked hCG takes about 10% of the total amount of hCG present in the blood.