Table 2.
Time interval (in hours) at each stage of cervical dilatation for nulliparous women
| Study | n | 2–3 cm | 3–4 cm | 4–5 cm | 5–6 cm | 6–7 cm | 7–8 cm | 8–9 cm | 9–10 cm | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| m | 5th | 95th | m | 5th | 95th | m | 5th | 95th | m | 5th | 95th | m | 5th | 95th | m | 5th | 95th | m | 5th | 95th | m | 5th | 95th | ||
| Zhang et al.7 | 1162 | 3.2 | 0.6 | 15.0 | 2.7 | 0.6 | 10.1 | 1.7 | 0.4 | 6.6 | 0.8 | 0.2 | 3.1 | 0.6 | 0.2 | 2.2 | 0.5 | 0.1 | 1.5 | 0.4 | 0.1 | 1.3 | 0.4 | 0.1 | 1.4 |
| Suzuki et al.24 | 2369 | 7.5 | 2.7 | 21.0 | 6.2 | 2.2 | 17.7 | 4.8 | 1.5 | 15.7 | 3.3 | 1.0 | 10.7 | 2.6 | 0.7 | 9.3 | 1.8 | 0.5 | 6.8 | 1.0 | 0.2 | 4.4 | 0.9 | 0.3 | 2.6 |
| Zhang et al.6 | 8690 | — | — | — | 1.20 | — | 6.60 | 0.90 | — | 4.50 | 0.60 | — | 2.60 | 0.5 | — | 1.80 | 0.40 | — | 1.40 | 0.40 | — | 1.30 | 0.40 | — | 1.20 |
| Zhang et al.21 | 27 170 | — | — | — | 1.8 | — | 8.1 | 1.30 | — | 6.40 | 0.80 | — | 3.20 | 0.60 | — | 2.20 | 0.50 | — | 1.60 | 0.50 | — | 1.80 | 0.50 | — | 1.80 |
| Shi et al.22 | 1091 | 2.67 | — | 7.20 | 2.00 | — | 4.20 | 1.71 | — | 4.00 | 1.00 | — | 2.50 | 1.00 | — | 2.30 | 0.90 | — | 2.10 | 1.00 | — | 2.50 | 0.33 | — | 1.00 |
| OT Oladapo et al. (unpubl. data) | 2166 | — | — | — | 2.82 | 0.60 | 13.33 | 1.72 | 0.38 | 7.83 | 1.19 | 0.23 | 6.17 | 0.66 | 0.09 | 4.92 | 0.25 | 0.02 | 3.10 | — | — | — | — | — | — |
| Pooled values | 42 648 | 5.28 | 2.00 | 1.46 | 0.92 | 0.70 | 0.55 | 0.52 | 0.49 | ||||||||||||||||
| Lower confidence bound | 5.07 | 1.89 | 1.39 | 0.89 | 0.68 | 0.53 | 0.50 | 0.48 | |||||||||||||||||
| Upper confidence bound | 5.46 | 2.11 | 1.52 | 0.96 | 0.73 | 0.57 | 0.53 | 0.51 | |||||||||||||||||
| Median rate of dilatation (cm/hour) | 0.19 | 0.50 | 0.68 | 1.09 | 1.43 | 1.82 | 1.92 | 2.04 | |||||||||||||||||
| n | m* | 1SD | 2SD | m* | 1SD | 2SD | m* | 1SD | 2SD | m* | 1SD | 2SD | m* | 1SD | 2SD | m* | 1SD | 2SD | m* | 1SD | 2SD | m* | 1SD | 2SD | |
| Chen et al.23 | 500 | — | — | — | 1.39 | 1.15 | 2.30 | 1.03 | 0.99 | 1.98 | 0.81 | 0.97 | 1.94 | 0.54 | 0.60 | 1.20 | 0.46 | 0.41 | 0.82 | 0.50 | 0.44 | 0.88 | 0.56 | 0.49 | 0.98 |
| Mean rate of dilatation (cm/hour) | — | — | — | 0.72 | 0.97 | 1.23 | 1.85 | 2.17 | 2.00 | 1.79 | |||||||||||||||
—, no data reported; 5th, 5th percentile; 95th, 95th percentile; m, median; m*, mean; SD, standard deviation.