Table 1.
Methodological quality assessment of included studies
| Study | Sequence generation | Allocation concealment | Blinding | Incomplete outcome data | Selective reporting bias | Other bias |
|---|---|---|---|---|---|---|
| Raziel A (2006) [28] | IVF identity number | Unclear | Unclear | Yes | Yes | Unclear |
| Nargund G (2001) [16] | Unclear | Unclear | Unclear | Yes | Yes | Unclear |
| Bjercke S (2000) [17] | Unclear | Yes | Unclear | Yes | Yes | Unclear |
| Mansour RT (1994) [13] | Unclear | Unclear | Yes | Yes | Yes | Unclear |
| Jamieson ME (1991) [29] | Unclear | Unclear | Unclear | Yes | Yes | Unclear |
IVF in vitro fertilization