Can maternal height predict shorter cervical length in asymptomatic low-risk pregnant women?

To evaluate the association between maternal height and cervical length in the first and second trimesters in low-risk asymptomatic pregnant women.

Maternal height and cervical length of 146 asymptomatic women with singleton pregnancies at low risk for preterm birth were measured during the first and second trimesters. Preterm birth was defined as birth before <37 gestational weeks. Correlations between maternal height and cervical length measurements were determined using Pearson correlation analysis. The women were also divided into three groups based on height percentiles: <25% (Group I), 25-75% (Group II) and >75% (Group III). Cervical lengths were compared among groups. Correlations between cervical length and maternal height and statistically significant differences in cervical length among height percentile groups were the main outcomes.

Maternal height was positively but weakly correlated with first and second trimester cervical lengths (p=0.047, r=0.167 and p=0.039, r=0.197 respectively). The mean first trimester cervical lengths were significantly different between the groups (p=0.04). There were no significant differences, however, in the mean second trimester cervical lengths among the three groups although the difference was close to significance (p=0.06).

Although our results indicate a relationship between maternal height and cervical length in our population, maternal height seems to have only limited value in identifying women to be screened for shorter cervical length in a low risk asymptomatic population.