[1] Sao Paulo State Univ Julio Mesquita Filho, Botucatu Med Sch, Postgrad Program Tocogynecol, Sao Paulo, Brazil
[2] Sao Paulo State Univ Julio Mesquita Filho, Botucatu Med Sch, Dept Gynecol & Obstet, Sao Paulo, Brazil
[3] Sao Paulo State Univ Julio Mesquita Filho UNESP, Botucatu Trophoblast Dis Ctr, Botucatu Med Sch Hosp, Botucatu, SP, Brazil
[4] Harvard Med Sch, Dept Obstet Gynecol & Reprod Biol, Boston, MA 02115 USA