Salient points regarding CL at 20–24 weeks
1 The measurement must be scrupu- lously performed under a standardized protocol.
2 Studies do not demonstrate the
efficacy of screening with CL in a low-risk population.
3 Funneling will increase the likelihood of PTB as an independent predictor, but it is no better a clinical performer than CL alone.
4 A dynamic cervix is probably a fore- runner of permanent shortening and may require a longer examination time todetect it.
5 Empiric early cerclage at 13 week is not a useful option in patientsat risk for cervical insufficiency.
6 Some highly selected patients,
representing a very small percentage of those with short CLs in the second trimester,may benefit from cerclage.
7 Any patient with a short CL should be worked up for intrauterine orintracervical infection. I think that the rarepatient who might benefit from a cerclage
should havea preprocedure amnio- centesis and fluid culture, particularly looking for ureaplasma. The ability to do a cervicalIL-8 may negate the need to sample amniotic fluid.