Metformin No metformin (n=159)Metformin (n=128) Age34.833 BMI27.227.8 HMG ampoules37.141.1 Oocytes retrieved23.818.8 Embryos tranferred2.83 Clinical pregnancies37.630.5 Moderate and severe OHSS*201 Khattab, Reprod Biomed Online, 2006