Typically, formula-fed infants who are growing well no longer need to feed at night by 6 months. Breastfed infants may continue a little bit longer, but typically no longer feed at night by 9 months. If your baby has been falling asleep independently at bedtime for a month but still waking to feed, you may want to consider weaning at night. Be aware that if you are breastfeeding, this may lead to a reduction in milk supply.
"My 3-month-old doesn't sleep through the night, and it's fine with me. I keep her in her crib or a bassinet until her 3 a.m. feeding, and then she joins my husband and me until we get up for work. She won't go in her crib unless she's already asleep, usually from nursing and rocking, but she'll fall asleep in her bassinet beside our bed. She's happy and we're happy, and even if it goes against the wisdom of the experts, it's working for us."
"There are good times to sleep-train and periods when it may be less likely to work," says developmental psychologist Isabela Granic, Ph.D., coauthor of Bed Timing: The 'When-To' Guide to Helping Your Child to Sleep. "This is because infants and toddlers go through mental growth spurts that make them especially clingy, fussy, and prone to night wakings. They're learning new cognitive skills and often don't sleep as well."