Is human fecundity changing? A discussion of research and data gaps precluding us from having an answer

Melissa M. Smarr, Katherine J. Sapra, Alison Gemmill, Linda G. Kahn, Lauren A. Wise, Courtney D. Lynch, Pam Factor-Litvak, Sunni L. Mumford, Niels E. Skakkebaek, Rémy Slama, Danelle T. Lobdell, Joseph B. Stanford, Tina Kold Jensen, Elizabeth Heger Boyle, Michael L. Eisenberg, Paul J. Turek, Rajeshwari Sundaram, Marie E. Thoma, Germaine M.Buck Louis