The two recent readers shared their stories with us regarding early pregnancies complicated by “low hormone levels” and subsequently loss of their babies. Many questions arise regarding what it means to have low human chorionic gonadotrophin (hCG – the ‘pregnancy test’ hormone) or progesterone levels and what can be done about it, if anything? Do low levels mean you will lose a pregnancy? Can low levels indicate other potential problems with a pregnancy? All of these are frequently asked questions relevant to many of our readers and I will try to address them after responding to our readers’ questions below…
• At Thu Dec 20, 03:24:00 PM 2007, siniamejia said…
I am approximately 5 weeks pregnant, and had my levels of hCG checked (because I was bleeding). My doctor said my levels were really low and also my progesterone levels were low and that it looks as if this pregnancy will not turn out to be healthy. My levels were 114 Saturday and only 145 today (5 days later). He says that I should have a D&C but I refused, so he told me that I will miscarry or should. I am so upset right now because I do not want to be the one to make the decision to have that done. I feel like maybe there still is hope and maybe a couple of days from now the bleeding will stop and the numbers will increase. I am still praying and I still have hope that my baby could still make it, but my doctor really doesn’t think so. I am so hurt, I never even imagined this. I have a 8 year old son and a 5 year old daughter, which were both high risk pregnancies. My son was born at 24 weeks and weighed 1 pound at birth. He is completely healthy and normal. With my daughter, I had early contractions the whole pregnancy, not to mention that I couldn’t hold food down and needed an IV everyday in the hospital. Could this mean that my husband and I can’t have anymore children. I am still young and I lost a lot of weight. I exercise and maintain a healthy life, why could this be happening to me? It’s so painful, emotionally. Please help. Thanks.
• At Fri Dec 21, 05:54:00 AM 2007, Kenneth F. Trofatter, Jr., MD, PhD said…
To siniamejia Dec 20: There is always hope, but I am afraid your doctor is correct in telling you this pregnancy will not make it. Your hormone levels are not only low, they have not risen appropriately. You have had two other children, and even if those pregnancies were complicated, that probably has nothing to do with what is going on with this pregnancy. The most common cause of an isolated miscarriage in a woman who has previously had successful pregnancies is a chromosomally abnormal baby. Fifteen to 20% of all pregnancies miscarry and MOST of those are babies that are not chromosomally normal. It is still your baby, and I know you will be sad and you will go through wondering about what "could I have done to prevent this and what could have been", but this is certainly no reason to think that you cannot ever have another baby.
With regard to a D&C, as long as you are not bleeding heavily or have any evidence of infection, you are not in any danger and don't need to do anything else at this time. Waiting is just fine under these circumstances. My only other concern is with your history of weight loss and hyperemesis with your last pregnancy. Some women who lose an excess amount of weight (and I do not know if that is true in your case) will become nutritionally depleted and/or hormonally ‘imbalanced’ and not ovulate regularly. This could also deleteriously impact your pregnancy success but if you are having regular cyclic periods, then this is not likely to be the issue in your case. My best wishes to you and thanks for reading. Dr T
• At Thu Dec 20, 10:58:00 AM 2007, Anonymous said… Hi, my wife just miscarried our 7 week old baby. Her hCG levels were about 2,000 at that time. The doctors said that her levels were pretty low when we did the first the pregnancy test two weeks ago. My question is could we have been able to prevent this miscarriage if they placed her on progesterone supplements early on in the pregnancy? Could there have been anything we could have done to prevent this miscarriage?
• At Fri Dec 21, 06:00:00 AM 2007, Kenneth F. Trofatter, Jr., MD, PhD said…
To Anonymous Dec 20: Progesterone probably would not have helped at the point it was found to be “low” and may actually have been contraindicated. If you have had other children, the most likely reason for the miscarriage is that the baby was chromosomally abnormal. Most of those babies are lost in first trimester. If this was a first pregnancy, or if your wife has any other medical problems, there may be other explanations - usually hormonal or immunologic in nature. I am sorry for your loss, but this is one situation in which you should not kick yourselves for having done anything 'wrong.' Miscarriage is always sad - wondering what was, what could have been, and what could we have done different, but if there are no underlying medical conditions to have contributed to the miscarriage, then the odds are you will be successful in the future. My thoughts and best wishes are with you. Thanks for reading! Dr T
As a focus for further discussion related to these queries, let’s start with progesterone. Following ovulation, what’s left of the follicle (the corpus luteum) begins to make the hormone progesterone that helps to prepare (decidualize) the lining of the uterus (the endometrium) to receive the fertilized egg, aiding attachment and implantation of the early embryo. With implantation, the fetal trophoblast cells start producing the hormone hCG that sends a ‘message’ back to the corpus luteum to ‘stay healthy and keep making progesterone.’ Production of progesterone by the corpus luteum is necessary to support the development of the placenta during the first 7-8 weeks of the pregnancy. After that point under normal circumstances, the placenta itself takes over progesterone production at a level sufficient to maintain the pregnancy.
Decreased progesterone production following ovulation or inadequate production of hCG or placental progesterone has been found to accompany pregnancy abnormalities that result in miscarriage. Defective production of these hormones may precede by weeks the identification or loss of an abnormal pregnancy (Hahlin, et al., Hum Reprod 1990;5:622–626) or ectopic (tubal) pregnancy (Yeko, et al., Fertil Steril 1987;48:1048–1050; Ledger, et al., Hum Reprod 1994;9:157–160). Indeed, there is good evidence to suggest that serum progesterone measured in early pregnancy is the most reliable single predictor of pregnancy outcome in natural conceptions (Al-Sebai, et al., Br J Obstet Gynaecol 1995;102:364–369; Daily, et al., Am J Obstet Gynecol 1994;171:380–383) even in the absence of a pregnancy detected by ultrasound (Elson, et al., Utrasound Obstet Gynecol 2003;21:57–61). Ioannides and colleagues (Human Reprod 2005;20:741-6) demonstrated that even in IVF pregnancies supplemented with progesterone, a single serum progesterone on day 14 post-oocyte retrieval and fertilization (4 weeks gestation), could “highly (but not completely) differentiate between normal and abnormal pregnancies.” Women with viable intrauterine pregnancies “had significantly higher serum progesterone levels (median: 430, 95%CI: 390–500 nmol/l) compared to those who had either an abnormal pregnancy (72, 48–96 nmol/l; P<0.001) or failed to conceive (33, 28–37 nmol/l; P<0.001).” It is interesting to point out that as the result of their findings, they hypothesized “that endogenous progesterone is already sufficient in viable pregnancies and that exogenous progesterone administration will not rescue a pregnancy destined to result in a miscarriage.”
Although progesterone is highly effective at differentiating normal from abnormal pregnancies, it is still not routinely used at most institutions for this purpose because of the expense, inexperience of provider interpretation, and the more widespread availability and high reliability of quantitative hCG testing. hCG can usually be detected by routine blood assays within 10-11 days following conception (7-8 days by highly sensitive assays) and in the urine at 12-14 days (just preceding or coincident with the time of expected menstruation). Serial quantitative blood testing of hCG is a useful approach to evaluation of early intrauterine pregnancy viability and ectopic pregnancies. In 80-90% of normal pregnancies, hCG levels will double every 48-72 hours, peak at 8-11 weeks gestation and then fall off to a stable lower level for the rest of the pregnancy.
If hCG levels are low for a calculated gestational age, this can indicate a nonviable or ectopic pregnancy. However, it is generally recommended that decisions regarding viability not be made by a single hCG level alone. It could be low simply because the pregnancy is not quite as far along as expected (e.g., in circumstances when women ovulate later in their cycles than expected or are not “sure” of their last menstrual period) or as the result of normal variation in hCG levels in different women and different pregnancies. More ominous are situations in which the hCG is not rising appropriately over time.
However, at low levels of hCG, the woman is rarely in immediate danger, even if she has an ectopic pregnancy, so the prudent approach in situations in which the pregnancy is desired is to simply wait, repeat the hCG levels periodically, every 2-3 days, and perform an ultrasound to look for evidence of an intrauterine pregnancy when the hCG level is at the point where that becomes possible. Usually a gestational sac can be seen within the uterine cavity between 4 and 5 weeks and when the hCG is in the range of 1000-2000 mIU/mL. By 6 weeks, a ‘fetal pole’ is usually visible and the hCG is > 5000 mIU/mL; and by 7 weeks, fetal cardiac activity is readily detectable and the hCG is > 20,000. I can relate many personal experiences with patients who started out with an unexpectedly low hCG that went on to have normal, healthy pregnancies, so patience is a virtue under these circumstances.