I was extremely fertile after my son was still born. I got AF back 5 weeks after I had him, and was pregnant on the second cycle. Miscarried that one, and pregnant again three weeks after the m/c bleeding stopped.
But, with my two living kids that breasted, no. AF came back at 9m with ds1, and dd is 8m and no AF. Can be fertile without ovulating.
Mama to Henry (01.07), Catherine (09.11), Audrey (04.14), Clare (09.15) and our newest addition, coming July 2017!