Table 4.

Subgroup analyses for the association between FIN and RPL

					Test for subgroup differences
Subgroup	No. of comparisons	MD (95%CI)	I2 (%)	P-value for heterogeneity	Chi2	P	I2 (%)
Region
Asia	5	1.86 [0.52, 3.19]	89	< 0.00001	4.08	0.40	2
Africa	2	7.92 [-4.78, 20.61]	94	< 0.0001
Europe	2	1.20 [-1.18, 3.58]	87	0.006
America	2	2.72 [1.13, 4.30]	0	0.45
Middle East	5	5.93 [0.71, 11.16]	97	< 0.00001
Definition of RPL
>  = 2	11	2.63 [1.43, 3.83]	89	< 0.00001	0.81	0.37	0
>  = 3	5	4.78 [0.25, 9.31]	97	< 0.00001
Matched confounders
No	8	1.02 [0.76, 1.27]	97	< 0.00001	11.00	0.0009	90.9
Yes	8	2.33 [1.60, 3.05]	55	0.03
Measurement timing
During pregnancy	4	7.82 [1.00, 14.63]	98	< 0.00001	2.55	0.11	60.8
Not during pregnancy	12	2.21 [1.25, 3.16]	82	< 0.00001
Exclusion of known factors
Yes	11	4.42 [2.45, 6.52]	96	< 0.00001	5.25	0.02	81.0
No	5	1.75 [0.58, 2.91]	60	0.04