HELP! Pregnant but he's waiting to tell his mom... 👶🏽🙄

So my boyfriend and I just found out that I was pregnant the Sunday before last. I understand that it is still very early in letting everyone know but I have let a few of my family members know about the pregnancy. I want him to tell his mom but he says he's waiting to tell her because he knows his mom talks a lot and once she knows, the whole world will know. He says he's going to tell her when he gets ready to but I'm so anxious for "her" to know at least since my mom knows already. Should I just be patient or should I be concerned? How long should I give him to tell her? Does it take men more time to become immune to what is happening? Lol