Helminth infection, fecundity, and age of first pregnancy in women Aaron D. Blackwell1,2,3,*, Marilyne A. Tamayo4, Bret Beheim2,5, Benjamin C. Trumble1,2,3,6,7, Jonathan Stieglitz2,5,8, Paul L. Hooper2,9, Melanie Martin1,2,3, Hillard Kaplan2,5, Michael Gurven1,2,31Department of Anthropology, University of California Santa Barbara, CA 93106, USA.2Tsimane Health and Life History Project, San Borja,