Table 1. Baseline patient characteristics of cycles with at least one measured βhCG resulting in a singleton delivery by mode of conception (n=2,054 cycles; n=1,821 people).

Characteristic	Autologous Fresh IVF (n=1,347)	Autologous Frozen IVF (n=454)	Donor IVF (n=253)
Maternal age (years)	36.1 (33.2–38.9)	35.8 (33.1–38.5)	42.8 (40.1–45.3)
Race
White	1,093 (81.1)	322 (70.9)	202 (79.8)
Asian	106 (7.8)	46 (10.1)	16 (6.3)
Black/African American	49 (3.6)	19 (4.2)	9 (3.6)
Hispanic	26 (1.9)	11 (2.4)	NR
Other	55 (4.1)	28 (6.2)	14 (5.5)
Not reported/unknown	18 (1.3)	28 (6.2)	NR
Married or partnered	1,254 (93.1)	404 (89.0)	212 (83.8)
The highest level of education achieved
College/associate’s degree or less	656 (48.7)	66 (15.4)	84 (33.2)
Graduate degree	504 (37.4)	75 (16.5)	86 (34.0)
Unknown	187 (13.9)	313 (68.9)	83 (32.8)
Gravidity
1	900 (66.8)	196 (43.2)	136 (53.8)
2	232 (17.2)	135 (29.7)	60 (23.7)
3+	213 (15.8)	123 (27.1)	57 (22.5)
Missing	2 (0.2)	0 (0.0)	0 (0.0)
Parity
1	1,274 (94.6)	417 (91.9)	233 (92.1)
2+	71 (5.3)	37 (8.2)	20 (7.9)
Missing	2 (0.2)	0 (0.0)	0 (0.0)
Year of delivery
2000-2005	454 (33.7)	3 (0.7)	56 (22.1)
2006-2011	478 (35.5)	70 (15.4)	72 (28.5)
2012-2018	415 (30.8)	381 (83.9)	125 (49.4)
Infertility diagnosis*
Male factor	294 (21.8)	35 (7.7)	9 (3.6)
Ovarian dysfunction	133 (9.9)	17 (3.7)	15 (5.9)
Tubal factor	104 (7.7)	11 (2.4)	4 (1.6)
Diminished ovarian reserve	65 (4.8)	6 (1.3)	82 (32.4)
Endometriosis	65 (4.8)	6 (1.3)	3 (1.2)
Uterine	34 (2.5)	5 (1.1)	0 (0.0)
Unexplained	426 (31.6)	53 (11.7)	6 (2.4)
Missing	151 (11.2)	304 (67.0)	76 (30.0)
Peak serum E2 (pg/mL)	1,327 (926–1,976)	--	--
No. of embryos transferred	2.0 (2.0–3.0)	1.0 (1.0–2.0)	2.0 (1.0–2.0)