Table 1.

Patient characteristics and treatment outcomes according to the FET protocol.

Characteristics and Treatment Outcomes	aFET	Ovulatory Cycle-FET (n = 286)	p-Value
	(n = 348)
Body mass index, kg/m2	26.1 ± 5.7	25.3 ± 5.4	0.088
Age, years	35.4 ± 6.5	35.3 ± 6.3	0.76
Infertility			0.66
Primary	96 (28%)	84 (29%)
Secondary	251 (72%)	202 (71%)
Parity			0.42
No	190 (55%)	147 (51%)
Yes	157 (45%)	139 (49%)
Smoker	56 (20%)	47 (19%)	0.91
Alcohol consumption	2 (1%)	5 (3%)	0.26
Cause of infertility (%)
Unexplained	9.4	5.3	0.062
Male factor	45.9	53.8	0.15
Oligo-ovulation	24.2	10.6	<0.0001
Mechanical factor	19	26.5	0.062
Endometriosis	1.5	3.8	0.11
Number of embryos transferred, mean ± SD	1.21 ± 0.46	1.22 ± 0.45	0.22
Last estradiol before transfer	159 (59.7–283)	205 (127–306)	0.003
Last progesterone before transfer decision	0.21 (0.1–0.4)	0.78 (0.29–1.32)	<0.0001
ESHRE score of the transferred embryos, average	2.38 ± 0.86	2.21 ± 0.71	0.042
KID score of the transferred embryos, average	4.68 ± 0.64	4.63 ± 0.67	0.43
ESHRE score for all transferred embryos, average	2.37 ± 0.81	2.17 ± 0.71	0.031
KID score for all available embryos, average	4.67 ± 0.63	4.61 ± 0.64	0.44
Endometrial thickness before transfer (mm)	9.15 ± 2.2	8.84 ± 2.2	0.25
Positive beta hCG per transfer	119/348 (34.2%)	131/286 (45.8%)	0.003
Clinical pregnancy per transfer	95/348 (27.3%)	118/286 (41.3%)	<0.0001
Delivery and ongoing pregnancy	67/348 (19%)	94/286 (33%)	<0.0001
Ongoing pregnancy	31/348 (9%)	43/286 (15%)	0.02
Delivery rate	36/348 (10%)	51/286 (18%)	0.007
Abortion	52/95 (54.7%)	37/118 (33%)	<0.0001
Ectopic pregnancy	2/95 (2%)	4/118 (3%)	0.5
Neonatal birth weight (grams)	3364 ± 497	3130 ± 664	0.13
Fetal anomalies	0	0	NS
Hypertension	1	4	NS
Preterm delivery	1	2	NS
Diabetes	5	3	NS