Metabolomic Prediction of Pregnancy Viability in Superovulated Cattle Embryos and Recipients with Fourier Transform Infrared Spectroscopy

Table 1

Day 60 pregnancy and birth predictions on PCA transformed spectra data derived from metabolomic analysis of spent culture medium (CM) of Day 6 in vivo embryos cultured in vitro for 24 h and transferred fresh to recipients on Day 7 in two laboratories (UNCEIA, France, and UTE-Bos, Spain).

Laboratory	Sample analyzed	Pregnancy endpoint	𝑁	Positive	Negative	𝑘	PCA	Accuracy	Sensitivity	Specificity	AUC
France	Embryo CM	Day 60	26	16	10	3	+	74.6±5.5	75.0±4.2	74.0±8.4	0.751±0.039
		Birth	26	14	12	3	+	68.5±7.6	69.3±7.6	67.5±9.2	0.655±0.075
Spain	Embryo CM	Day 60	23	13	10	3	+	74.8±3.9	67.7±7.1	84.0±6.9	0.718±0.024
		Birth	23	12	11	3	+	66.9±4.2	58.3±6.8	76.3±4.7	0.625±0.032
France + Spain	Embryo CM	Day 60	49	29	20	3	−	64.4±1.4	57.5±2.7	74.4±5.8	0.604±0.029
		Birth	49	26	23	3	−				<0.6

𝑁: culture medium or plasma samples analyzed. Positive: samples that correspond to pregnancy/birth. Negative: samples that do not correspond to pregnancy/birth.
𝑘: adjustable model parameter of 𝑘-nearest neighbor classification algorithm.
PCA: principal component analysis (+: applied; −: did not improve the results when applied).