[1] Ibis Reprod Hlth, 2067 Massachusetts Ave,Suite 320, Cambridge, MA 02140 USA
[2] Univ Penn, Dept Obstet & Gynecol, 1000 Courtyard,3400 Spruce St, Philadelphia, PA 19104 USA
[3] Amer Coll Obstetricians & Gynecologists, 409 12th St,Southwest,POB 96920, Washington, DC 20090 USA
[4] Univ Calif San Francisco, Bixby Ctr Global Reprod Hlth, Adv New Stand Reprod Hlth ANSIRH, Dept Obstet Gynecol & Reprod Sci, 1330 Broadway,Suite 1100, Oakland, CA 94612 USA