A single serum test for measuring early pregnancy outcome with high predictive value

The normal variabilities of the menstrual cycle

“…It is noteworthy that using a different hCG test that equally detects hCG and hCG-H, we detect the first production of hCG or implantation earlier than the Wilcox group (4 days compared with 6 days), even though our test is notably less sensitive (1 mIU/mL compared with 0.13 mIU/ mL). As published, hCG-H is the principal or only hCG form produced at the time of implantation (18,19,27). The use by Wilcox and colleagues of an hCG test that poorly detected hCG-H may have methodologically limited the earliest detection of hCG.…”

Hyperglycosylated human chorionic gonadotropin and the source of pregnancy failures

“…Measurement of hCG-H concentration is slightly less effective, total hCG (regular hCG þ hCG-H) even less effective, and regular hCG alone the least useful as an indicator. Other studies have shown that hCG-H is a better discriminator for term and failing pregnancies than total hCG from time of the missed menses until 8 weeks of gestation (14,18). During this implantation period, a total hCG (hCG-H plus regular hCG) test will detect 42% of failures at a 2.9% false-positive rate, and an hCG-H test will detect 79% of failures at the same false-positive rate (18).…”

“…During this implantation period, a total hCG (hCG-H plus regular hCG) test will detect 42% of failures at a 2.9% false-positive rate, and an hCG-H test will detect 79% of failures at the same false-positive rate (18). No advantage has been found in measuring hCG doubling time over a single measurement of total hCG (18).…”

“…Other studies have shown that hCG-H is a better discriminator for term and failing pregnancies than total hCG from time of the missed menses until 8 weeks of gestation (14,18). During this implantation period, a total hCG (hCG-H plus regular hCG) test will detect 42% of failures at a 2.9% false-positive rate, and an hCG-H test will detect 79% of failures at the same false-positive rate (18). No advantage has been found in measuring hCG doubling time over a single measurement of total hCG (18).…”

“…As for the role of implantation in pregnancy outcome, an imbalance in hCG-H could be at the root of many pregnancy failures. Multiple studies now have shown that unduly low proportions of hCG-H mark spontaneously aborting pregnancies, from the time of the missed menses until failure (14,17,18).…”