Maternal height as a risk factor for Caesarean section due to failure to progress in labour

Aust N Z J Obstet Gynaecol. 1999 May;39(2):152-4. doi: 10.1111/j.1479-828x.1999.tb03360.x.

Abstract

We examined for a regional sample of the New Zealand population, the relationship between maternal height and an increased risk of emergency Caesarean section due to arrested labour, to identify a height below which the risk of Caesarean section increases markedly and to quantify the risk of a Caesarean section for a range of maternal heights. The data of nulliparous singleton pregnancies over the period 1994-1998 was sorted into 2 study groups, one resulting in emergency Caesarean section for arrested labour and the other a group of women who had normal vaginal delivery requiring no intervention. The means and standard deviations of these 2 groups were found and 99% confidence intervals calculated. They were analysed for statistical difference and then a logistical regression calculation tried to identify a height at which the risk of a Caesarean section increased suddenly. There were 81 women in the Caesarean section group and 997 in the normal vaginal delivery group. Mean heights and confidence intervals were 161.0 cm (158.9-163.1) and 164.6 cm (164.0-165.2) respectively. There was a statistically significant difference between these means (p<0.001) but logistic regression analysis showed that risk of Caesarean section increased gradually with decreasing height, and even then did not reach more than 30% risk until a height of less than 140 cm. Low maternal height was associated with increased risk of Caesarean section due to labour arrest. Because the likelihood of having a normal vaginal delivery was still very good (>80 %) at modest degrees of short stature, this risk factor alone is unlikely to affect management. However the combination of other risk factors with maternal height may be of clinical use.

MeSH terms

  • Body Height*
  • Cesarean Section*
  • Female
  • Humans
  • Obstetric Labor Complications*
  • Pregnancy
  • Retrospective Studies
  • Risk Factors