Table 2.

Birth outcomes by number of oocytes retrieved, oocyte source, and day of transfer for cycles with transfer of one embryo.

Oocyte Source	Day of Transfer	# Oocytes Retrieved	N	Length of Gestation (mean weeks, SD)	Birthweight (Mean grams, SD)	Z-score (Mean, SD)	Percent SGA	Percent LBW
Autologous	Days 2–3	1–5	1132	38.5±2.0	3261±559	−0.04±0.96	9.1	8.3
Oocytes		6–10	773	38.5±2.0	3279±566	0.01±0.97	7.3	7.6
		11–15	396	38.2±2.4	3161±625	−0.12±0.97	9.6	12.6
		16–25	300	38.6±1.9	3289±582	−0.04±1.04	10.7	8.7
		≥26	104	38.7±1.7	3339±526	0.06±0.88	5.8	6.7
		p Value for trend		0.69	0.84	0.72	0.83	0.44
		Adjusted p value*		0.90	0.86	0.85	0.89	0.34
Donor	Days 2–3	1–5	27	38.6±1.6	3223±585	−0.15±1.14	14.8	14.8
Oocytes		6–10	58	38.0±2.8	3318±688	0.23±1.04	8.8	8.8
		11–15	59	38.2±2.6	3323±668	0.20±0.94	5.1	6.8
		16–25	64	38.3±2.6	3395±549	0.21±0.96	7.8	6.3
		≥26	31	38.3±2.2	3207±612	−0.06±0.98	6.5	16.1
		p Value for trend		0.85	0.86	0.75	0.31	0.73
		Adjusted p value*		0.82	0.80	0.77	0.25	0.65
Autologous	Days 5–6	1–5	241	38.0±2.2	3276±593	0.20±0.96	4.2	7.1
Oocytes		6–10	1001	38.1±2.1	3285±552	0.14±0.97	5.9	7.2
		11–15	1545	38.1±2.1	3262±577	0.11±0.93	5.4	7.3
		16–25	2336	38.1±2.1	3251±578	0.08±0.96	7.2	8.1
		≥26	942	37.9±2.4	3231±620	0.12±0.95	6.4	9.6
		p Value for trend		0.04	0.02	0.23	0.10	0.02
		Adjusted p value*		0.05	0.07	0.54	0.18	0.04
Donor	Days 5–6	1–5	9	38.8±1.1	3461±552	0.18±1.17	11.1	0.0
Oocytes		6–10	140	37.9±2.6	3177±640	0.03±0.97	8.0	12.1
		11–15	345	38.1±2.5	3259±620	0.11±0.94	4.7	11.9
		16–25	752	38.3±2.1	3268±588	0.07±1.00	8.9	10.0
		≥26	481	38.1±2.4	3255±614	0.10±0.93	6.9	8.9
		p Value for trend		0.54	0.81	0.78	0.52	0.16
		Adjusted p value*		0.56	0.76	0.89	0.57	0.14

^*The p value for trend was adjusted for female age and prior births.