Additional file 1: Supplementary Figure 1. Principle component analysis reveals DHEA+4 (arrow) as a potential outlier and was removed from subsequent analysis. Supplementary Figure 2. (a) MS/MS spectra of pyridine at increasing eV. (b) Follicular fluid testerosterone levels as measured by metabolomics. DHEA+, POR subjects on DHEA supplementation and DHEA- control without DHEA supplementation. Supplementary Figure 3. (a) Dot Plots of Linoleic acid and L-Valine after removal of women with endometriosis (N=5), (b) ROC curves of Linoleic acid and L-Valine after removal of women with endometriosis (N=5). Supplementary Figure 4. Histograms of estradiol, anti-müllerian hormone (AMH), DHEA-sulphate and insulin Growth Factor-1 (IGFBP-1) concentrations as determined by immunoassay. NS, not significant. Supplementary Figure 5. Scatter plots of (a) progesterone with IGF-1 (Pearson r: 0.6757, p<0.01), (b) linoleic acid with estradiol (Pearson r: 0.7016, p<0.01), (c) linoleic acid with IGF-1 (Pearson r: 0.8203, p<0.01), (d) glycerophosphocholine negatively correlated with AMH (Pearson r: -0.5815; p<0.05), (e) valine with serum-free testosterone (Pearson r: -0.8774; p<0.0001). Linear regression lines are shown.