Subgroup analyses
Since there was statistical heterogeneity for IVF outcomes across
studies (CPR: I2 =47.4, p <0.001; LBR:I2 =62.9, p <0.001), subgroup analyses
and random-effects meta-regression were utilized. In subgroups
classified by treatment type, studies used TA was found to be
statistical heterogeneity (CPR: I2 =61.5, p
<0.001; LBR: I2 =68.3, p =0.001)
(Table 1 ). Therefore, the meta-regression analyses were
restricted to TA methods. With regard to TA and TEAS on CPR, control
type (no acupuncture, sham or placebo) was found to be the potential
source of heterogeneity (p = 0.043, respectively) (Table 2 ).
When compared with no treatment, TA did improve CPR (18 trials, OR=1.85,
95%CI=1.51 to 2.28). However, no significant difference was found
between TA and sham control (penetration: 4 trials, OR=1.89, 95%CI=0.93
to 3.82; non-penetration: 6 trials, OR=1.04, 95%CI=0.76 to 1.43).
Similar findings were observed for LBR results, TA group was
significantly higher than that from no treatment (10 trials, OR=1.36,
95%CI=1.07 to 1.73), but not from sham control group (9 trials,
OR=1.42, 95%CI=0.95 to 2.11). While according to acupuncture sessions,
TA performed for 2 or more than 3 times showed significant effect on CPR
(17 trials, OR=1.51, 95%CI=1.18 to 1.94; 9 trials, OR=1.99, 95%CI=1.52
to 2.60; respectively), while performed for 1 session found no
significance (2 trials, OR=1.47, 95%CI=0.34-6.39). It was also an
increasing improvement for TEAS if three or more treatments were
administered (5 trials, OR=2.34, 95%CI=1.58 to 3.48) (Tables
2-3 ). The additional results of the effects of different acupuncture
methods by baseline CPR, OPR or LBR of no treatment group were shown inFigure S4 . Studies with lower control group rates of CPR showed
larger effects of TA (OR=2.14, 95%CI=1.63 to 2.81) than that with
higher control group rates of CPR (OR=1.61, 95%CI=1.22 to 2.13).