The membrane layer sweep rate of success is generally very good after 37 months with twins. Am 37 and destroyed all 5 maternity because of cevix.frist that is incompetent one at 20 weeks didn`t know about i/c.secound at 2 months.third at 21 months with cerclage, had a rupture membranes.forth at 6weeks don`t know what happen and last on 17 april 10 at 20 months with cerclage.Continue reading