Overbearing MIL

La
My mother-in-law, who lives 20 minutes from us, calls my husband multiple times a day. I can understand if it is something serious, but it's for no reason...she'll ask "what are you doing?" Every time she calls and that's pretty much it. My husband even gets aggravated by it sometimes. And she'll invite herself over. It's not "can I stop by?" Or "are you busy?" It's "I'm coming over in a little while." It drives me nuts. 
Last night, for example, we went out on a "date night" to cheddar's and were  going to Best Buy afterward. As soon as our food comes, his phone rings. He answers it and it's his mom, letting him know she wants to come over. She asks what he's doing. He tells her we are at cheddar's, then says "well, come on." I guess she had mentioned she wouldn't mind eating out, too. She asks what we're doing AGAIN and my husband sighs and says "what do you do at a restaurant? We're eating." He then says "I know" and hangs up. I asked what the "I know" was for and he said she told him I need to be careful about Zika. Uh, duh! 
I guess it's the fact that I'm 18 weeks preggo and trying to soak up our last date nights and time together but her constant calls aggravate me to no end. And they're so random!!! My folks live 2.5 hours away and they don't call me several times a day, or even every day.
Can anyone else relate?? I can't say anything to my husband because he already thinks I don't like his mother.