Hello....first thing you should know is- infertility means unable to concieve even after one year of unprotected regular Sex. If that's the case it may be due to numerous causes, in womens- it might be due to uterine abnormality,hormonal imbalance, fibroid in uterus,sometimes infection like T.B would have scarred fallopian tube which might be a cause,certain medications, obesity etc...consult nearest infertility specialist for detailed clinical examination they will do the needful.