2.2.2 All stages of labour
2.2.2.1 Analysis of pain level Five studies assessed incidence of
pain at 3 levels including Ⅰ, Ⅱ and Ⅲ, in which pain at level Ⅲ had the
greatest impact on participants. For meta-analysis, the incidence of
pain at level Ⅲ was converted into a dichotomous variable. We pooled the
studies and found that auricular acupressure significantly reduced the
incidence of pain at level Ⅲ compared to the controls (RR=0.17, 95%CI
[0.13, 0.24], p <0.05), with no heterogeneity
(I2=0%) (Figure 8). Sensitivity analysis indicated
that the results were robust.
2.2.2.2 Duration of each stage of labour Six studies investigated
duration of each stage of labour. Summary results showed a significant
reduction in duration of the first stage in the study groups compared to
the control groups (MD=-2.57, 95%CI [-3.69, -1.45],p <0.05), with statistically significant heterogeneity
(I2=81%, 97%, 99%). Nevertheless, there were no
significant differences in the second and third stage of labour (Figure
9). Sensitivity analysis indicated that the results were robust.
2.2.2.3 Postpartum blood loss Two trials reported postpartum
blood loss. Pooling the data of the studies showed no significant
difference between auricular acupressure intervention and obstetric care
routine, with significant heterogeneity (I2=97%)
(Figure 10). Sensitivity analysis indicated that the results were
robust.
2.2.2.4 Incidence of spontaneous delivery Pooled analysis of four
studies that assessed incidence of spontaneous delivery showed no
significant difference between the study groups and the control groups
with significant heterogeneity (I2=84%) (Figure 11).
Sensitivity analysis indicated that Ye et al.[25]appeared to add to significant heterogeneity. Removing this study
eliminated this heterogeneity (I2=0%), and changed
the effect size of the pooled result (Z = 2.89, P = 0.004), but the
difference is still not significant.
2.2.2.4 Incidence of caesarean section Three studies reported
incidence of caesarean section. A fixed effect model was applied, for
there was no evidence of heterogeneity (I2=0%).
Summary results indicated a lower incidence of caesarean section in
auricular acupressure groups compared to the control groups (RR=0.36,
95%CI [0.20, 0.65], p =0.0006) (Figure 12). Sensitivity
analysis indicated the results were robust.