Table 2: Methodology, findings, and main conclusions derived from metabolomics studies on maternal and neonatal urine.

Population studyGestational age at examinationMetabolomic analysisMain resultsSignificance/take-home messagesReferenceAuthor, year

48 GDM cases versus 23 controlsThird
trimester
MSIncreased urinary excretion of P-IPG, positive correlation with blood glucoseMetabolomic identification of P-IPG is a potential marker of insulin resistance, may predict fetal growth alterations in GDM patients[33] Scioscia et al., 2007

9 PE cases versus 84 controlsFirst
trimester
Elisa-based assayRapid raise of P-IPG (sensitivity and specificity of 88.9% and 62.7%, resp.)Metabolomics by multiple assessment of samples might predict preeclampsia [32] Paine et al., 2010

3083 pregnancies positive to the screening of Smith-Lemli-Opitz syndromeSecond
trimester
GC/MS 16α-OH-DHEA, urine total estriol. Fetal steroid sulfatase deficiency 98% detection rate, 95% CI 92–99Metabolomics analysis of Maternal urine steroids is effective in detecting STSD. Possible use for diagnosing ADHD and CGDS (common in association with STSD) [31] Marcos et al., 2009

75 pregnancies (13 healthy)Potential of the tandem use of MS and NMR for metabolomics studies of urine and amniotic fluid in pregnant women
13 fetal malformations Hippurate, amino acids
20 predisposition to GDM Second
trimester
UPLC-MS NMRNo relevant changes[30] Graça et al., 2012
6 preterm deliveryMethionine, phenylalanine, hystidine, hexose (possibly glucose)

26 preterm FGR versus 30 preterm appropriate for gestational age Neonates1H NMRMyoinositol, sarcosine, creatine, and creatinineMetabolomics might identify FGR and contribute to the clinical management of FGR neonates[34] Dessì et al., 2011

GDM: gestational diabetes mellitus; MS: mass spectrometry; P-IPG: inositol phosphoglycan P type; PE: preeclampsia; GC/MS: gas chromatography-mass spectrometry; STSD: steroid sulfatase deficiency; ADHD: attention deficit-hyperactivity disorder; CGDS: contiguous gene deletion syndrome; UPLC-MS: ultra performance liquid chromatography-mass spectrometry; NMR: nuclear magnetic resonance spectroscopy; 1H NMR: proton nuclear magnetic resonance spectroscopy; FGR: fetal growth restriction.