Cervix length measurement by transvaginal ultrasonography
The utility of transvaginal cervix length measurement
for assessing the risk of preterm birth has been
well documented in a structured analysis of 14 trials
that included a total of 2258 pregnant women (12).
The accepted cutoff value for cervix length is ≤ 25
before GW 24 (OR 2.76, 95% CI 2.41–3.17). The
predictive value of a negative test is high (92%);
this implies that pregnant women who are found
not to have a shortened cervix can be reassured,
and unnecessary therapeutic measures can be
avoided.
demonstrated (OR 0.79, 95% CI 0.66–0.95), but due
to considerable methodological deficiencies, these
results cannot be generalized (11).