1. Is early age at menarche a risk factor for endometriosis
Is early age at menarche a risk factor for endometriosis? A systematic review and meta- analysis of case-control studies 
Kelechi E. Nnoaham, M.D., Premila Webster, M.D., Jharna Kumbang, M.D., Stephen H. Kennedy, M.R.C.O.G., Krina T. Zondervan, D.Phil. 
Fertility and Sterility 
Volume 98, Issue 3, Pages e6 (September 2012)
DOI: /j.fertnstert
Copyright © 2012 American Society for Reproductive Medicine Terms and Conditions

2. Figure 1
Forest plot of 18 included studies evaluating association between early menarche and endometriosis.
Fertility and Sterility  , e6DOI: ( /j.fertnstert )
Copyright © 2012 American Society for Reproductive Medicine Terms and Conditions

3. Figure 2
Meta-analysis of included studies presented by rigor of control for potential confounders.
Fertility and Sterility  , e6DOI: ( /j.fertnstert )
Copyright © 2012 American Society for Reproductive Medicine Terms and Conditions

4. Supplemental Figure 1
Scatter plot of Newcastle-Ottawa scale (NOS) score and study effect sizes. CI = confidence interval.
Fertility and Sterility  , e6DOI: ( /j.fertnstert )
Copyright © 2012 American Society for Reproductive Medicine Terms and Conditions

5. Supplemental Figure 2
Funnel plot, using data from 18 case-control studies of early menarche and endometriosis risk, with effect sizes displayed on the horizontal axis.
Fertility and Sterility  , e6DOI: ( /j.fertnstert )
Copyright © 2012 American Society for Reproductive Medicine Terms and Conditions

6. Supplemental Figure 3 Egger plot. CI = confidence interval.
Fertility and Sterility  , e6DOI: ( /j.fertnstert )
Copyright © 2012 American Society for Reproductive Medicine Terms and Conditions