What Causes Problem In Conceiving After Fibroid Operation?

Hi. I am 41 years old and have a 15 yr old daughter. In the past 5 years I have had 3 miscarriages. the last 2 were in yr 2009 and the doctors said i had fibroids. I had the fibroids removed in April 2010 but I am unable to conceive yet. What can be the problem. Before the operation, pregnancy used to be quite easy