Table 2.

Cycle and HRT–FET parameters according to estradiol exposure duration.

	Short (8-9 days) exposure	Intermediate (10-11 days) exposure	Prolonged (12-14 days) exposure	p
All cycles	(n=980)	(n=746)	(n=275)
Cycle-related parameters
Stimulation duration (days)	10.6 ± 1.2	10.7 ± 1.2	10.6 ± 1.2	0.651
Number of oocytes retrieved	17.8 ± 9.4	17.1 ± 9.3	17.6 ± 9.9	0.290
Number of metaphase-2 oocytes	13.8 ± 7.7	13.6 ± 7.8	13.9 ± 8.5	0.725
Number of 2PN oocytes	10.9 ± 6.3	10.8 ± 6.3	11.2 ± 6.4	0.547
Number of blastocysts obtained	4.9 ± 3.4	4.7 ± 3.4	5.0 ± 3.7	0.432
E2 level on trigger day (pg/mL)	2855 ± 2248	2901 ± 2221	2958 ± 2244	0.793
P4 level on trigger day (ng/mL)	0.98 ± 0.76	1.01 ± 0.72	0.99 ± 0.83	0.666
EL on trigger day (mm)	10.1 ± 1.8	9.9 ± 1.9	9.9 ± 2.1	0.563
Transfer cycles	(n=959)	(n=717)	(n=259)
HRT-related parameters
Estradiol exposure duration (days)	8.7 ± 0.5	10.5 ± 0.5	12.4 ± 0.6	<0.001
On cycle day 2–3
E2 level (pg/mL)	43 ± 15	43 ± 16	45 ± 15	0.574
P4 level (ng/mL)	0.36 ± 0.23	0.39 ± 0.22	0.39 ± 0.21	0.130
On progesterone initiation
E2 level (pg/mL)	370 ± 158	434 ± 201	400 ± 171	<0.001
P4 level (ng/mL)	0.27 ± 0.19	0.31 ± 0.23	0.28 ± 0.18	0.001
EL (mm)	9.6 ± 1.3	9.7 ± 1.4	9.7 ± 1.5	0.868
Number of blastocyst transferred				0.460
Single blastocyst transfer	800 (83.4)	585 (81.6)	219 (84.6)
Double blastocyst transfer	159 (16.6)	132 (18.4)	40 (15.4)
Quality of blastocysts transferred
High-quality	1.11 ± 0.31	1.10 ± 0.30	1.08 ± 0.26	0.492
Average-quality	1.16 ± 0.36	1.14 ± 0.35	1.17 ± 0.37	0.822

Values are given as mean (± standard deviation) or number (percentage).

NA, Not applicable.