Ignore the comment or change the subject.
Share information on breastfeeding with the other person.
Make a joke about the situation or yourself to lighten the mood.
Show that you are recognizing the person’s viewpoint by asking further questions without agreeing or responding to the criticism.
Be empathetic — show that you understand the other person’s feeling and meaning.
And a new way......
Speed away on a moped to avoid further conflict.
Over at Breitbart they say......A mother in China was pulled over by police after allegedly breastfeeding her baby while driving a moped through the streets in Yuzhou, Henan province. According to witnesses, the child, about 18-months old, was crying as the mother weaved through traffic. "So she suddenly lifted up her T-shirt, whipped out her breast and started to feed him on the move," said one driver. A police spokesman said "She was risking her life, her son's life and the lives of all the other road users...We told her that if she carried on we would confiscate her bike."
I am guessing the police let her go because they had no idea how to actually handle this situation.