8 months old still waking every 2 hours

She wakes up every 2 hours at night the only way to get her back to sleep without crying is to feed her. After I breastfeed her I lay her in her crib and leave out sometimes she go right to sleep and sometimes she cries a little thn go to sleep but she still wakes up every 2 hours. Some night she will have one 3 hour stretch. And i tired pumping and giving her a bottle with cereal in it, thinking it will keep her full and she will sleep longer but nope still every 2 hours. Any suggestion will be great because this mama is tired plus I'm pregnant again so it makes me tired.