When my mom was pregnant with me in 1962, she lived on a diet of coffee and cigarettes; she'd have tuna fish for breakfast, one hard boiled egg for lunch. Her doctor wouldn't 'let' her gain more than I think 14 pounds, because 'he didn't want her coming back after the baby was born complaining about how much weight she gained'. The best part? My mother was an RN, and at this point had been managing the recovery room for several years. But in those days, what Doctor says is gospel.
I changed doctors when at my first prenatal visit, he said "we don't like our girls to gain more than 17 or 18 pounds." Yeah, that's not patronizing in any way.
I have a CW, who is quite thin, both pre and post her two kids. when she was pregnant with one of them, her dr. asked if she was having any snacks, and she said yes, and then asked what. She said oh, a piece of fruit, maybe a few crackers, something like that. Now this CW eats very healthily, and doens't have an extra ounce on her. she's actuallly gained some weight sicne she had her kids, and she looks good; she was quite thin before.
Said dr. poo pooed her and said well, if you feel you NEEd a snack, have a tic tac. Yes, she actually said that. CW switched dr.'s shortly after that, but will still retell the "Dr. Tic Tac" story every now nad then,.