First of all, what is HCG? HCG stands for human chorionic gonadotropin, and it is a hormone secreted naturally during pregnancy. HCG can be found in the expectant mother’s urine even before she is aware that she is pregnant, even before she is aware that her menstrual cycle is disrupted by pregnancy.
You have probably seen a urine pregnancy test (usually a small plastic stick with a “window”) which is held in the expectant mother’s urine flow to determine whether or not she is pregnant – the test is looking for the presence of HCG to confirm pregnancy.
HCG can also be checked for in the blood, but there is usually no need for this unless there is a specific reason for wishing to confirm a pregnancy earlier than you can with the urine method – even then, the difference in detection rate is so small that it’s never usually required for any reason.
Some expectant mothers become extremely concerned about HCG levels during pregnancy, as it has been linked to the increased risk of miscarriage and birth defects. However, as you will see through the rest of this article, those claims are misleading – HCG doesn’t actually affect any part of your pregnancy and is nothing to be concerned about in itself.
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What Is the Purpose of HCG?
n simple terms, there isn’t one! HCG is produced naturally by the placenta, which has the function of nourishing the growing embryo. Although it is produced as part of this process, it is a by-product, meaning that is isn’t actually required for a healthy pregnancy.
It will not affect the growth of your baby, nor his or her development inside or outside the womb. There is no link to birthdefects, and having low or high levels does not cause miscarriage. There is absolutely nothing that you can do to influence the level of the hormone in your blood or urine, and nor should you seek to – there’s no point!
It can allow physicians to roughly date the pregnancy (you may have heard this referred to as ‘how far along’ the pregnancy is), as there is usually a formula for how much HCG is produced at different points in the pregnancy.
It can be detected by a blood test around 11 days after conception, and in urine roughly 12 days to two weeks afterwards. From this point, you can expect levels to double around every 72 hours; using this formula, physicians are able to make an approximate guess at how far the mother is into her pregnancy.
Levels will peak before 12 weeks or the end of the first trimester, and then slowly decline before forming a baseline which will remain for the rest of the gestation.
Despite this, it is not recommended to use HCG to date pregnancy – it is far more accurate and safer to use ultrasound scanning.
What if My HCG Levels Are“Wrong?”
Well, firstly this isn’t something that you should worry about – if you have reason to be concerned, your physician will discuss this with you. You may have what is referred to as “slow rising” HCG – this simply means that the hormone is being secreted at a lower level than expected (hence why it is not recommended that levels be used for dating scans). Usually, this will rectify itself, and your pregnancy will be perfectly normal.
In some cases, slow to rise HCG can be an indicator of problems, such as ectopic pregnancy. If you believe you could be pregnant and are experiencing any abdominal pain, it is important that you consult a qualified medical practitioner as soon as possible. It is unlikely that your HCG levels would be the first indicator of an ectopic pregnancy, however, and this could only be confirmed with an ultrasound scan.
Lower than expected levels of the hormone might also be an indicator of what is known as a blighted ovum, or of a miscarriage – again, this is not something that should be guessed at, and your obstetrician who is measuring your HCG will always talk to you if either of these is a possibility.
If your HCG levels are much higher than expected there are several possible reasons. The first is simply that you have miscalculated your dates and you are just further along than you expected!
A more unusual reason would be what is known as a “molar” pregnancy, which is where an egg implants into the uterine lining but fails to continue to develop. Again, as with ectopic pregnancy, your physician will advise you if it is a possibility, although it is unlikely.
A far more common reason for high HCG levels is, of course, the presence of multiple embryos – it could be a sign that you are expecting twins or even triplets! Again, this can only be confirmed with a scan, and you should not let high HCG levels concern you unless your physician has told you that there is a reason to be concerned.
So, How Do I Know What My HCG Levels Are?
Well, the short answer is – you won’t! Usually, it’s only normal for HCG levels to be tested if there are concerns about the pregnancy, or, as already mentioned, there is a suspicion of multiple embryos (for example, if you have been taking fertility treatments). Again, if you do require regular testing of your hormone levels, your obstetrician will be able to advise you on this and discuss the reasons for it with you.
Before you rush to your GP and ask for HCG testing regularly throughout your pregnancy, please do remember that it doesn’t affect anything – having high levels is not “good” and nor is having low levels. As there is such a massive normal range, it’s not even always sure what high or low levels are, so there’s no benefit from additional testing to you or your baby – it would just mean extra trips to the hospital or medical center when you don’t need them!
My Friend/Sister/Cousin Is Also Pregnant, and Her Levels Are Much Higher!
First of all, don’t panic! There is a massively wide range of normal when it comes to HCG, and as already explained your levels would probably drop off or increase as expected at some point. There’s no point in comparing your levels (or any other part of your pregnancy for that matter!) to someone else; put simply, everyone is different, and no two pregnancies are alike. This is often true for the same mother, let alone two different people. So, if you find that you do have levels that differ from your friends or the other ladies in your antenatal class, it’s nothing to worry about and is probably completely meaningless.
So What Does All of This Mean?
In summary, HCG is nothing to worry about unless your OBGYN tells you that there is a concern. It’s a naturally occurring by-product of the placenta that is nourishing your growing fetus and has no actual effect on your pregnancy itself.
Having higher or lower levels than are normally expected will not cause any changes in your pregnancy, but may (or may not) be a symptom of something unusual, such as multiple pregnancies (twins or triplets – more than this would be extremely uncommon unless you are on fertility medication).
If you currently have high or low levels of HCG, it’s very likely that they will level out slowly over the duration of your pregnancy, and by the time you get round to giving birth, they will have normalized completely (not that it matters if they don’t!).
HCG is not a hormone that will affect your pregnancy, nor will it make it more or less likely that you will suffer a miscarriage or problems during your gestation. There is nothing that you can do to affect your levels (e.g. there are no supplements, dietary or other measures that you can take to change it), and even if you could do it, it wouldn’t be relevant, as HCG does not affect your pregnancy or baby in and of itself.
Really, the only function of this hormone is to confirm your pregnancy, and after this has happened you should just forget about it unless advised otherwise – you have plenty of other things to think about! If people are comparing your levels to those that they had when they were pregnant, or to what they’ve heard are normal levels, it’s usually pretty safe to say that they can be ignored.
If, after reading this, you are still concerned about your HCG levels, it is best to check with your midwife or OBGYN. It almost without doubt that if your levels were a cause for concern, they would already have alerted you to the fact, and either explained what those concerns are or referred you for further tests. However, pregnancy can be a stressful enough time without worrying over things alone, and if you have genuine concerns talking them over with your healthcare professional is always the best approach.