ContextAlthough shortened cervical length has been consistently associated with
spontaneous preterm birth, it is not known when in gestation this risk factor becomes
apparent. ObjectiveTo determine whether sonographic cervical findings between 16 weeks'
and 18 weeks 6 days' gestation predict spontaneous preterm birth and whether serial
evaluations up to 23 weeks 6 days' gestation improve prediction in high-risk women. Design,
Setting, and ParticipantsBlinded observational study performed between March 1997 and …

The National Institutes of Health has recommended administration of antenatal
corticosteroids to all patients at risk of preterm delivery. A single course is known to be
effective, but many clinicians routinely repeat corticosteroid therapy until 34 weeks'
gestation. The efficacy and safety of single vs. weekly courses of antenatal corticosteroids
were evaluated in a multicenter trial. Pregnant women eligible for the study were between
24 and 32 weeks' gestation and had experienced preterm labor, preterm premature rupture …