Table 1.

Basic characteristics of the EFL and LPS groups

Characteristics	EFL protocol(n = 1401)	LPS protocol(n = 2129)	Standardize diff.	P-value
Maternal age (y)	30.17 ± 4.32	30.06 ± 4.51	0.02 (-0.04, 0.09)	0.47
Paternal age (y)	31.27 ± 5.38	31.21 ± 5.38	0.01 (-0.06, 0.08)	0.775
Maternal BMI (kg/m2)	22.48 ± 3.11	22.67 ± 3.15	0.06 (-0.00, 0.13)	0.068
Antral follicle count	13.69 ± 6.35	13.14 ± 5.83	0.09 (0.02, 0.16)	0.043
No. of oocytes retrieved	11.78 ± 5.05	11.32 ± 5.23	0.09 (0.02, 0.16)	0.01
Primary infertility	712 (50.97%)	1081 (51.01%)	0.00 (-0.07, 0.07)	0.978
Tubal factor	745 (53.18%)	1069 (50.21%)	0.06 (-0.01, 0.13)	0.085
PCOS	163 (11.63%)	160 (7.52%)	0.14 (0.07, 0.21)	< 0.001
Male primary infertility	769 (55.44%)	1161 (54.89%)	0.01 (-0.06, 0.08)	0.749
Fertilization method			0.12 (0.05, 0.19)	< 0.001
IVF	1021 (72.88%)	1436 (67.45%)
ICSI	380 (27.12%)	693 (32.55%)
No. of transferred embryos	1.90 ± 0.30	1.91 ± 0.42	0.01 (-0.06, 0.08)	0.793
Embryo transfer stage			0.09 (0.02, 0.16)	0.011
Cleavage-stage embryo	1279 (91.29%)	1887 (88.63%)
Blastocyst	122 (8.71%)	242 (11.37%)
Gestational age at delivery (wk)	38.52 ± 1.63	38.85 ± 1.68	0.19 (0.11, 0.28)	< 0.001
Time of delivery (wk)
<36	215 (15.74%)	255 (12.18%)	0.10 (0.03, 0.17)	0.003
37–41	1119 (81.92%)	1793 (85.63%)	0.10 (0.03, 0.17)	0.004
≥ 42	0 (0.00%)	14 (0.67%)	0.12 (0.05, 0.18)	0.002
Delivery mode			0.05 (-0.01, 0.12)	0.117
vaginal delivery	293 (21.45%)	405 (19.27%)
cesarean delivery	1073 (78.55%)	1697 (80.73%)
Number of deliveries			0.05 (-0.02, 0.12)	0.127
Singletons	995 (71.02%)	1562 (73.37%)
Multiples	406 (28.98%)	567 (26.63%)
Congenital malformation	23 (1.64%)	50 (2.35%)	0.05 (-0.02, 0.12)	0.149
GDM	44 (3.14%)	19 (0.89%)	0.16 (0.09, 0.23)	< 0.001

Note: Data are presented as mean ± SD for continuous variables or n (%) for categorical variables

BMI = body mass index; PCOS = polycystic ovary syndrome; ICSI = intracytoplasmic sperm injection; IVF = in vitro fertilization; GDM = gestational diabetes mellitus