Objective: To evaluate the pattern of cervical dilatation in live singleton pregnancies with spontaneous onset of labor and to compare any differences among nulliparas (P ara 0) and multiparas (Para >or=1).
Material and methods: Descriptive statistics are presented for 238 consecutive labor patients with spontaneous onset, >or=37 weeks gestation, live singleton pregnancy and who had spontaneous vertex delivery at the University of Ilorin Teaching Hospital, Nigeria, from May 2004 to June 2004. Pre-labor rupture of membrane and referred cases were excluded.
Results: The mean cervical dilatation on presentation and duration of labor before presentation in labor ward among nulliparas were 5.40 cm and 6.66 hours; and among multiparas, 6.45 cm and 5.15 hours, respectively, the overall mean being 6.12 cm and 5.63 hours, respectively. The average time spent to achieve full cervical dilatation from time of arrival in labor ward was longer in nulliparas (4.80 hours) than in multiparas (3.60 hours) (t test not significant; P> 0.05). Overall mean total length of first stage of labor was 9.36 hours, while the total length of first stage of labor was 11.03 hours and 8.53 hours for nulliparas and multiparas, respectively (difference is significant; t test P< 0.05). Significant negative correlation existed between parity and total length of first stage of labor. Mean cervical dilatation rate in labor ward (active phase) was higher in multiparas (1.83 cm/h) than in nulliparas (1.76 cm/h), but the difference was not significant (t test P> 0.05). No significant correlation existed between rate of cervical dilatation and maternal age, gestational age and fetal size.
Conclusion: It is evident from this study that higher the parity the shorter the length of first stage of labor; however, significant difference existed only in the first half of first stage of labor between nulliparas and multiparas. Mean rate of cervical dilatation was greater than the WHO-specified and Philpott's lower limit of 1 cm/h in active phase of labor.