Predictors of cephalopelvic disproportion in labour a tertiary hospital in Bayelsa state, Nigeria
Background: Cephalopelvic disproportion (CPD) is a disparity between the fetal head and maternal pelvis, usually in the absence of fetal or maternal jeopardy. It is a very common complication during labour, and it is associated with a very high caesarean section rate. Delay in intervention could lead to obstructed labour. Short stature, fetal macrosomia and pelvic abnormalities are common risk factors. The aim of this study was to determine the influence of maternal height, age, clinical pelvimetry, and birth weight on cephalopelvic disproportion in the Niger Delta University Teaching Hospital, Bayelsa State.
Materials and Methods: This is a retrospective case controlled analysis of 5,205 parturients who received antenatal care, and delivered at the Niger Delta University Teaching Hospital, from January 2010 to December 2015. Of these, 588 patients who had cephalopelvic disproportion were identified. Data concerning their maternal age, parity, height, pelvimetry, gestational age at delivery, and fetal demographic characteristics were collected and analyzed. This was compared to a control group of 588 parturients who were randomly selected among parturients who had spontaneous vaginal delivery (SVD) during the study period.
Results: A total of 5,205 women delivered during the period of study, out of these, 588 women had cephalopelvic disproportion, giving a rate of 11.3%. Majority of the women who had CPD were nulliparous (47.6%). Women who were 150.0 cm tall or less were 3 times more likely to have cephalopelvic disproportion in labour than those who were over 150.0cm tall. P = 0.001, Odds Ratio = 3.69 [CI, 2.49 -5.47]. Women who delivered babies with birth weight ≥ 4000 grams had significantly more cephalopelvic disproportion, than those who delivered babies with birth weights of 2501 – 3999 grams. Odds Ratio = 0.22, p = 0.001 [CI, 0.14 -0.33]. There is a significant negative correlation between maternal height and parity with cephalopelvic disproportion. [r = -295, p = 0.001] and [r = -197, p = 0.001] respectively. There is also a significant positive correlation between birth weight and gestational age at delivery with CPD [r = 0.24, p = 0.001] and [r = 0.149, p = 0.001]. Linear regression analysis of the independent variables reveal that maternal height was the biggest
predictor to CPD. Coefficient of determination R2 = 0.089(8.9%), F= 112.2, p = 0.001. Conclusion: Short stature is independently associated with an increased risk of intrapartum caesarean section in Nigerian women. We advocate for an early recourse to caesarean section to avoid undue morbidity.
Key words: maternal height, parity, age, birth weight, cephalopelvic disproportion, caesarean section.