The association of a cervical length of <25 mm in high-risk pregnancies on neonatal morbidity and mortality in preterm infants.

ABSTRACT

PURPOSE: To evaluate and compare the effects of a short cervix (<25 mm) on neonatal morbidity and mortality as opposed to a normal cervical length (≥25 mm). The predictive value of a short cervix on neonatal outcome is also investigated. METHODS: Preterm infants who were admitted to the neonatal intensive care unit and whose mothers had undergone a pre-delivery evaluation for cervical length (CL) and cervical cultures were included in the study. Infants were stratified into two groups based on CL measurements (Group 1, CL < 25 mm; Group 2, CL ≥ 25 mm). RESULTS: A total of 203 infants were included in the final analysis. Group 1 consisted of 105 neonates while Group 2 had 98 newborns. Cervical culture positivity rate was 46.7 % (n = 49) in Group 1 compared to 19.4 % (n = 19) in Group 2 (p = 0.0001). Frequencies of early onset neonatal sepsis (EOS) in Group 1 and Group 2 were 31.5 and 18.4 %, respectively (p = 0.032), whereas respective frequencies of proven sepsis in the two groups were 18.1 and 8.2 % (p = 0.037). A CL < 25 mm was found to increase the risk of cervical culture positivity, EOS and proven EOS by odds ratios of 3.63, 2.03 and 2.48, respectively. CONCLUSIONS: This is the first clinical study to demonstrate a significant link between CL and each of cervical culture positivity, EOS and neonatal morbidity and mortality. Preterm infants born to high-risk mothers with short CL should be monitored closely for the risk of EOS.