Fulfill every craving, keep her off her feet. Have plenty of healthy food around at all times. Be careful of gestational diabeties, that can be very dangerous.
When she was pregnant she ate well but nothing out of the ordinary.
She got huge during her second pregnancy. Just imagine a short lady with an ass so fat that when she sat in a lawn chair it squeezed through the arms of the lawn chair.
Wife gained only about 10-15 pounds for our first child together two years ago. Course, she was already 300 so it didn’t matter. Our little man is happy and healthy. She put on about a hundred pounds for her first pregnancy years ago, though.
Checking back in here to add that certain birth control methods can cause and keep weight gain propensity around a while. Years ago, my wife’s second pregnancy happened despite her receiving the “depo” shot beforehand. She got pregnant anyway, and as she puts it, changed her body to make it look like she’d been fat her whole life when she really hadn’t been.
While is tempting to take advantage of hormones during pregnancy to encourage weight gain and enjoy your partners body filling out to its maximum extent the priority should always be ensuring a healthy pregnancy for the sake of the baby.