Many things can be responsible for having a miscarriage like;
Although it is advised that the woman is prepared mentally before trying to make a baby, but you can always try as soon as possible. Ensure that you speak with your doctor about your decision and for their opinion.
Technically, getting pregnant a month after a miscarriage is a good thing; but you should however register for antenatal as soon as possible so that your health care provider can monitor you closely.
I hope this helps?