Table 4.

Clinical outcomes before and after matching.

	Unmatched			Matched
	Control n = 3973	Case n = 70	P value	Control n = 195	Case n = 65	P value
ET cycles	2134	32		110	32
No. of embryo transferred	2355	35		126	35
1 (%)	88.1 (1881)	90.6 (29)	1.000	85.5 (94)	90.6 (29)	0.565
2 (%)	11.9 (253)	9.4 (3)		14.5 (16)	9.4 (3)
Biochemical pregnancy rate (%)	7.0 (149)	3.1 (1)	0.722	5.5 (6)	3.1 (1)	1.000
Early miscarriage rate (%)	11.4 (114)	7.1 (1)	1.000	1.9 (1)	7.1 (1)	0.372
Clinical pregnancy rate (%)	46.9 (1000)	43.8 (14)	0.726	49.1 (54)	43.8 (14)	0.595
Implantation rate (%)	44.0 (1036)	40.0 (14)	0.637	45.2 (57)	40.0 (14)	0.581

Note:.

ET, embryo transfer.

Categorical variables were presented as% (n).