i am 16 week pregnent, concived on 5th IUI , 1st time pregnent and only 25 year old female, how long I must takeTab. dubagest 300SR, Tab. Duphaston & Tab. Oosure, even though it is written that you should use Tab. dubagest 300SR for 12 weeks, my doctor is still prescribing all above Tab, and asked to continue till 18th week ?????? Is all safe ???