My wife got NT scan on 12 weeks and 2 days and we came to know that her cervical canal is short of 2.85 cm in scan. When our gynec checked physically then she informed us it is even smaller (around 1cm). She has advised us to go for cervical cerclage. However my wife has placenta previa condition as well which becomes critical situation for cervical cerclage as it might hurt the placenta. Our questions are: 1. How safe is it to wait by following bedrest till the placenta goes up from the cervix os? 2. Can vaginal progesterone help to keep the cervix intact till the time situation becomes suitable for cervical cerclage?