Table 2.

Likelihood of Embryos Transferred ≥3 versus 1–2 by Maternal Age Categories^*

		All		<35 years		35–40 years		>40 years
	N, pregnancies	6,073		2,392		2,764		917
Variable	Categories	AOR	95% CI	AOR	95% CI	AOR	95% CI	AOR	95% CI
Mother’s Age	<35	1.00	Reference
(years)	35–40	3.84	3.30, 4.47
	>40	15.50	12.21, 19.67
Diagnoses	Male factor	0.65	0.55, 0.77	0.53	0.38, 0.73	0.65	0.52, 0.80
	Ovulation disorders	0.76	0.62, 0.94			0.67	0.50, 0.89
	Tubal factor	1.23	1.02, 1.47			1.30	1.04, 1.63
	Other factor	1.22	1.02, 1.45	1.82	1.31, 2.54
Oocyte Source	Autologous	1.00	Reference					1.00	Reference
	Donor	0.15	0.09, 0.25					0.34	0.18, 0.65
ICSI	No	1.00	Reference	1.00	Reference	1.00	Reference
	Yes	1.45	1.23, 1.71	2.00	1.43, 2.81	1.40	1.13, 1.73
Assisted Hatching	No	1.00	Reference	1.00	Reference	1.00	Reference	1.00	Reference
	Yes	1.79	1.56, 2.07	1.87	1.40, 2.49	1.67	1.39, 2.00	1.63	1.10, 2.42
Embryo State	Fresh	1.00	Reference	1.00	Reference	1.00	Reference
	Thawed	4.17	2.90, 5.99	17.63	6.75, 46.05	3.01	1.91, 4.75
Day of Transfer	5–6	1.00	Reference	1.00	Reference	1.00	Reference	1.00	Reference
	2–3	4.34	3.21, 5.88	7.03	2.84, 17.37	4.34	2.96, 6.34	4.72	2.77, 8.04

^*Models adjusted for all factors in the table