<qa>  What is the size of the sample size?This is a double blind- a randomized controlled study of prophylactic LMWH in women at low risk for VTE following a cesarean section procedure. The sample size is 300 patients, Eligible, consenting, and randomized participants will receive once-daily injections of study drug 4,500 IU Tinzaparin Sodium Innohep within 12- to 24-hours postpartum and continue for two weeks versus Placebo in the other arm and follow for six 6 weeks postpartum. 