everyone is different...
some women can conceive whilst exclusively breastfeeding and some can't.
With all of my children, I have not had cycles return until I finished BF so I could not have conceived whilst BF. But you may find your cycles return soon.
Basically though, you might as well not worry about TTC until your cycles DO return because you can't ovulate and NOT get a period. Once you ovulate, you'll either be pregnant or you'll get your period. so if you wait until your cycles return, you will only have missed one single solitary chance at conceiving.

good luck!