Table 1.

Univariate and biomarker identification studies of candidate metabolites for pregnancy endpoints birth and day-62 in culture medium (CM) of embryos transferred with vitrified/warmed embryos (CM samples from N = 36 ETs).

	p Value		Pregnancy	Univariate Study			Biomarker Discovery Study
Metabolite	BB 1	Day-6-E 2	Endpoint	p-Value	Open	Pregnant	p-Value	FCh	ROC-AUC	Open	Pregnant
Glyceryl monostearate	0.406	0.077	Birth	0.023	2454 ± 698	940 ± 468	0.060	2.829	0.670	11/17	11/18
Capric acid	0.364	0.742	Birth	0.048	329 ± 68	188 ± 45	0.021	4.472	0.728	10/17	15/19
Palmitic acid	0.507	0.341	Birth	0.089	17,719 ± 2992	12,460 ± 1978	0.051	5.381	0.669	12/17	12/19
Stearic acid	0.350	0.188	Birth	0.019	75,827 ± 9612	51,951 ± 6356	0.016	5.899	0.743	13/17	14/19
Stearic acid	0.350	0.188	D-62	0.023	75,692 ± 11,580	52,453 ± 6092	0.022	5.612	0.733	11/15	14/21

Tendencies 0.05 < p < 0.09 are in bold. p values from major effects are shown: bull breed (BB ¹) and embryonic stage on Day-6 (Day-6-E ²). FCh: Log fold-change in concentrations (open/pregnant). p values: Kruskal-Wallis test (Glyceryl monostearate) or General Linear Model (GLM) procedure (Capric, Palmitic, and Stearic acids), Bonferroni correction (p < 0.05) (Univariate study) and T-test (Biomarker discovery study). In contrast, glyceryl monostearate (one sample deleted as out layer 1200× mean value), capric acid, and stearic acid concentrations were significantly lower in embryos that reached birth (p < 0.05), and palmitic acid tended to decrease (Table 1). None of those metabolites was affected by bull breed, but glyceryl monostearate concentrations tended to differ at Day-6 between morula and blastocyst stages (p = 0.077). ROC-AUC: Receiver Operator Characteristic—area under curve.