Table 2.

Average metabolite concentrations (mmol/kg) and percent change of significantly different metabolites (16 of 21) in 2nd vs. 3rd trimester amniotic fluid samples

Metabolite	2nd Trimester (Mean ± SD)	3rd Trimester (Mean ± SD)	Percent change	P (Wilcoxon)
Alanine	0.860 ± 0.229	0.228 ± 0.132	−73.5	<0.001
Betaine	0.00846 ± 0.00206	0.0133 ± 0.0058	+56.7	<0.002
Citrate	0.740 ± 0.217	0.399 ± 0.137	−46.0	<0.001
Creatine	0.154 ± 0.084	0.097 ± 0.053	−37.2	0.008
Creatinine	0.0124 ± 0.0058	0.0247 ± 0.011	+99.5	<0.001
GPC	0.0424 ± 0.0407	0.0181 ± 0.0178	−57.4	<0.001
Glutamine	0.219 ± 0.106	0.310 ± 0.166	+41.6	0.029
Glutamate	1.10 ± 0.26	0.319 ± 0.305	−71.0	<0.001
Glucose	5.96 ± 1.66	2.41 ± 1.69	−59.4	<0.001
Isoleucine	0.0847 ± 0.0889	0.0409 ± 0.0512	−51.7	0.043
Lactate	20.0 ± 5.1	15.4 ± 4.1	−23.3	0.001
Leucine	0.0787 ± 0.0318	0.0240 ± 0.0230	−69.5	<0.001
Lysine	0.719 ± 0.196	0.270 ± 0.209	−62.4	<0.001
Pyruvate	0.0659 ± 0.0103	0.0299 ± 0.0286	−54.6	<0.001
Succinate	0.0562 ± 0.0624	0.0842 ± 0.0663	+49.9	0.007
Valine	0.828 ± 0.288	0.323 ± 0.179	−60.9	<0.001

GPC glycerophosphocholine