In fact, many women will not gain weight after pregnancy. As long as they go to the hospital for regular checkups, doctors now generally tell them when and how much weight gain is reasonable. Of course, some people don't eat much because of morning sickness, or because they are thinner, so they don't eat fat.
Let's start with the first one. People who use scientific and reasonable methods to control their diet during pregnancy generally know more about modern life. You can look at the food of celebrities during pregnancy. I have seen what Christine ate during her pregnancy before, and the nutrition is very balanced. In fact, the calories are not very high, such as boiled vegetables, chicken breast, boiled eggs and so on. And there is no oil and water. It is estimated that it is also beneficial for the child to absorb nutrition, so she doesn't look fat when she is pregnant.
Also, morning sickness is very serious. We all know that pregnant women's morning sickness is their pregnancy reaction. In severe cases, they will spit out everything they eat, which is very uncomfortable. I met a relative of mine who was like this when she was pregnant. She is not a very thin person because she is haggard and even loses weight after morning sickness. People like this can't help it. She can't eat anything, but she must see a doctor to recuperate.
There are also those who are ultra-thin and not fat. People like this can't help it. You can only envy them. They often don't get fat after eating all kinds of nutritious soups made by their mother-in-law, but if they are thoroughly studied, there may be traces to follow, but I'm not an expert, so I won't say much.
So now pregnant women are not based on obesity, as long as they have comprehensive nutrition.