Revised criteria for the diagnosis of pregnancy failure with endovaginal ultrasound * Crown-rump length
[greater than or equal to] 7 mm without a heartbeat * Mean sac diameter of [greater than or equal to] 25 mm with absence of an embryo * Lack of an embryo [greater than or equal to] 2 weeks after a prior ultrasound demonstrated a gestational sac without a yolk sac * Lack of an embryo [greater than or equal to] 11 days after a prior ultrasound demonstrated a gestational sac with a yolk sac
Given the inherent inter--and intraob-server variation in ultrasound measurements, he and his colleagues favor more conservative criteria for the definitive diagnosis of early pregnancy failure: a crown-rump length
cutoff of greater than 7 mm instead of 5 mm, and a mean gestational sac diameter cutoff of more than 25 mm.
Accuracy of gestational age estimation by means of fetal crown-rump length
The crown-rump length
measurements of fetuses of women who screened positive were significantly shorter than fetuses of women for whom a negative screen result was obtained.
We individually weighed each pup and measured its crown-rump length
using a graduated ruler.
Adam determined that six baseline biomarkers were significantly associated with miscarriage at the 20th percentile: history of subfertility bleeding score of two on a five-point scale, gestational age of the fetus, fetal crown-rump length
of 4 mm, and serum levels of progesterone and hCG (32 nmol/L and 1,500 iU/L, respectively).
The fetus weighed 164 g and had a crown-rump length
An embryo's crown-rump length
and fetal heart rate greater than 100 beats per minute predicted viability at 5-6 weeks post conception in a separate study presented at the annual meeting of the Pacific Coast Reproductive Society in Indian Wells, Calif.
Level II evidence supports use of crown-rump length
in the first trimester, which provides accurate dating and reduces the postdate risk to just 5%, in contrast to the 10%-15% rate with last menstrual period.