Hi, Fertyl is a drug which we use to increase the No. of Ova to increase for ovulation. it increases your chances of pregnancy, if you are not getting pregnant because of ovulation problem. As it increase the number of ova, there are more chances that more than one ovum can get fertilize. So chances of twin pregnancy increases relatively as compared to those women who become pregnant naturally. Chances of Dizygotic twins ( Unidentical twins) would be 10 out of 100 pregnancies which result due to These drugs, as compare to 0.3% to 4% ( depends on Race, age and parity). Usually chances of Identical twins do not increase with these drugs. Doses of fertyl also do not directly affect the chances of Multiple pregnancy as usually we increase the dose when smaller dose is not giving the desired result. You must also take Vitamin D, which has proven beneficial effect on fertility in recent studies. I hope I have answered your question. If you have any further query, you are most welcome. Best wishes Dr Hamdani