A borderline result is generated by some assays when the hCG level is between 5 and 25 mIU/mL. Samples reported as borderline are considered indeterminate, and clinicians should request a repeat test within 48 to 72 hours or obtain a quantitative serum hCG.
False positive/borderline results may be seen after undetected early spontaneous abortion, post delivery/miscarriage, post hCG injections or fertility drugs, post blood transfusion, in some malignancies (e.g. ovarian tumour/molar pregnancy) and in patients with interfering antibodies.
"Low hCG levels may represent a very early pregnancy or a pregnancy that is ending in miscarriage," says Dr. Lang. Other causes include blighted ovum (the fertilized egg fails to develop properly) and ectopic pregnancy (the embryo implanted somewhere outside of the uterus—usually the fallopian tube).
It has been previously suggested (10) that a 53% rise after 2 days will identify 99% of pregnancies that are viable, when the initial hCG <5000 mIU/mL. The current data suggest that this is likely true for women with an initial hCG value below 1500.
There's a wide range of normal when it comes to hCG levels, so high or low numbers don't usually cause concern. In fact, up to 25% of healthy pregnancies don't have hormone levels that double every two days, says Michele Hakakha, M.D., an obstetrician and co-author of Expecting 411.
Dropping hCG levels in the first trimester over the course of two to three days is usually the sign of an impending miscarriage. This is especially true for people experiencing symptoms of miscarriage such as heavy vaginal bleeding. Decreasing levels of hCG in the second and third trimester usually aren't a concern.
That said, hCG levels vary from person to person and pregnancy to pregnancy, so hCG levels are not definitive to determine a twin pregnancy. Some people have high hCG levels and only give birth to one baby; others have exceptionally low hCG levels and give birth to multiples.
It can be tempting to try remedies or foods that purportedly help raise your hCG levels. Unfortunately, there's no way to change your hCG levels or make them go up. What's more, hCG levels reflect information about your pregnancy, but changing them wouldn't address the cause of any potential problems.
Day by day, the measure of the hormone increases. However, there would only be a slight increase during the first three days after implantation. A rapid increase in the hCG levels is noticed after almost 6 days. From day 9 to day 12, the hCG levels are supposed to be at their peak.
What does a borderline result mean? A borderline result means that the test was between. normal and abnormal.
Borderline. Take no action – This means that the doctor has looked at the result and deemed it to be just outside of the normal range and the result is not concerning. Abnormal, but expected.
Laboratory Tests
An abnormal pregnancy is identified by the level of β‐hCG not doubling in 48 hours; a 66% rise in the β‐hCG level over 48 hours represents the lower limit of normal for a viable intrauterine pregnancy (IUP). Fifteen percent of viable IUPs have a less than 66% increase in β‐hGC in 48 hours.
PRL pulses caused a progressive inhibition of spontaneous HCG pulsatility. In conclusion, stress-related hormones affect placental HCG secretion in vitro. The involvement of these factors in impairing early pregnancy development is suggested.
While mean hCG follows a log-quadratic trajectory during the first week of detectability, there is high variability across pregnancies. Later implantation may reflect characteristics of the uterus or conceptus that slow hCG production.
The hCG levels in female-bearing pregnancies increase significantly, whereas they decrease in male-bearing pregnancies [1–3].
With detailed statistical analysis (ROC curve) they concluded that an hCG level of 76 mIU/mL was a suitable cut-off point for predicting viable pregnancy with 80% sensitivity and 82% specificity. The positive predictive value for a viable pregnancy at this level was 87% and the negative predictive value was 74%.
What are the symptoms? Low hCG levels that result from a miscarriage or an ectopic pregnancy are usually accompanied by abdominal pain, with or without vaginal bleeding.
Blood test results are about 99 per cent accurate and can detect lower amounts of hCG than urine pregnancy tests. The two main types of blood pregnancy test include: Quantitative blood test – measures the exact amount of hCG in the blood and can give you an estimate of how far along the pregnancy has progressed.
They also stated that the greatest concentration of maternal urinary hCG was present from the 6th to the 14th week of pregnancy when nausea and vomiting were mostly encountered.
Before 22-24 weeks, a non-viable pregnancy is when a baby delivered has no chance of survival, even if there is still a heartbeat in the uterus.
The addition of folic acid to the perfusate mitigated the decrease in hCG. Conclusions: Formic acid rapidly transfers across the placenta and thus has the potential to be toxic to the developing fetus.