My husband is attracted to bigger women

While my husband and I were dating we broke up for a few months because he said he was physically attracted to bigger/ thicker women. Then, he came back around and we started dating again and few months after that he propose and now we’re married. However, after I had my baby he keeps mentioning that he wants me to be the same size I was while I was pregnant. I’m 5’5” and 140. When we were dating I was was 125. When I was pregnant I was 189. Well I noticed lately that when we go out, he checking out women that are bigger/thicker. And now it’s causing me to have some insecurities that I didn’t have before. I love the size I am now and do not want to gain weight for him. He has some areas that I would not normally find attractive like his bald head, skin complexion (I like darker men) and his gut. I am lost on how to handle this situation. Men check me out all the time with or without him. I also don’t make it noticeable if I glance at an attractive guy. Ladies, please help me out on how to handle this situation. What should I do?