Relation of cervical length at 22-24 weeks of gestation to demographic characteristics and obstetric history

• Main Authors: Palma-Dias R.S., Fonseca M.M., Stein N.R., Schmidt A.P., Magalhães J.A.
• Format: Article
• Language: English
• Published: Associação Brasileira de Divulgação Científica 2004-01-01
• Series: Brazilian Journal of Medical and Biological Research
• Subjects: Cervical length; Preterm delivery screening; Transvaginal sonography; Perinatal medicine
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000500016

Preterm delivery is the main cause of neonatal death and ultrasonographic cervical assessment has been shown to be more accurate than digital examination in recognizing a short cervix. This is a cross-sectional study, involving 1131 women at 22-24 weeks of pregnancy, designed to determine the distribution of cervical length and to examine which variables of demographic characteristics and obstetric history increase the risk of a short cervix (15 mm or less). The distribution of maternal demographic and obstetric history characteristics among patients with cervical length £15 mm was analyzed and compared to the findings for the general population. Risk ratios (RR) between subgroups were generated from this comparison. Median cervical length was 37 mm and in 1.5% of cases it was 15 mm or less. The proportion of women with a short cervix (<=15 mm) was significantly higher among patients with a low body mass index (RR = 3.5) and in those with previous fetal losses between 16-23 weeks (RR = 33.1) or spontaneous preterm deliveries between 24-32 weeks (RR = 14.1). We suggest that transvaginal sonographic measurement of cervical length be performed as part of a routine midtrimester ultrasound evaluation. There are specific variables of demographic characteristics and obstetric history which increase the risk of detecting a short cervix at 22-24 weeks.