Table 1.

Demographic and clinical characteristics of FETs in the two groups

Variable	Group A (n=133)	Group B (n=329)	p-value
Maternal age at OPU (yr)	32.00±4.61	31.95±3.86	0.914
Pattern of infertility
Primary	47 (35.3)	116 (35.3)	0.987
Secondary	86 (64.7)	213 (64.7)	0.987
Factor of infertility
Female	77 (57.89)	210 (63.83)	0.234
Male	31 (23.31)	56 (17.02)	0.118
Both	24 (18.05)	63 (19.15)	0.783
Unexplained	1 (0.75)	0	0.115
Clinical pregnancy rate	82 (61.65)	221 (67.17)	0.258
Implantation rate	82 (61.65)	221 (67.17)	0.258
Multiple pregnancy rate	3/82 (3.66)	7/221 (3.17)	0.832
Miscarriage rate	22/82 (26.83)	47/221 (21.27)	0.305
Live birth rate	57/82 (69.51)	172/221 (77.83)	0.134
Birth weight (g)	3,196.84±496.53 (n=57)	3,236.25±519.82 (n=172)	0.609

Values are presented as mean±standard deviation or number (%). Group A, day-5 poor-quality blastocyst transfer group; Group B, day-6 high-quality blastocyst transfer group.

FET, frozen-thawed embryo transfer; OPU, oocyte pick-up.