[1] Natl Inst Child & Human Dev, Reprod Biol & Med Branch, NIH, Bethesda, MD USA
[2] George Washington Univ, Sch Publ Hlth & Hlth Serv, Dept Epidemiol & Biostat, Washington, DC USA
[3] George Washington Univ, Biostat Ctr, Rockville, MD USA
[4] Int Headquarters, Endometriosis Assoc, Milwaukee, WI USA