OBJECTIVE:

To clarify the relationship between
maternal height and cesarean rate due to cephalopelvic disproportion (CPD) in
singleton pregnancies among ethnic groups of relatively short stature.

METHODS:

A retrospective cohort study was
performed on Thai singleton pregnancies at gestational age of more than 34
weeks. Logistic regression analysis was performed to correlate the maternal
height and a risk for CPD. The short stature was defined by a cut-off value at
5th percentile ranking. Odds ratio for CPD was determined.

RESULTS:

Of 11,026 recruited, 9,198 were available
for analysis. Considering cut-off value of 145 cm, short stature was
significantly associated with higher rate of CPD with odds ratio of 2.4 (95% CI
1.8-3.0). The odds = exp(4.048 - 0.042 × Ht). After control of other variables,
the relationship between maternal height and rate of CPD was still high.

CONCLUSION:

Mothers with short stature were
significantly correlated with a higher rate of CPD, even after control of birth
weight, parity and type of attendance. Clinical points could be drawn from this
study including (1) definition of short statue must be developed for particular
geographic or ethnic groups. In Thai population, using 145 cm as a cut-off
value, odds of CPD is 2.4; (2) Probability of CPD may be estimated by maternal
height as a single variable or multiple variables using logistic regression
equations.