Hi gentlemen. I'm sorry to invade your board, but I could really use some male perspective right now. I am 39 weeks, so I'm seriously not sure if I just have hormones and anxiety going on right now, or if this is a legit concern.
My boyfriend, and father of the baby (both of our firsts) is a commercial diver. He has been out on an inland job for about 2 months now. I am not a big phone talker. Usually our conversations are 5 minutes or less. Our normal pattern was to check in once while he was on his way to work early in the morn, and once when he got off work and I was on my way to work in the evening. I work night shift as a nurse. He started working out and going to the gym for 1.5-2 hours after work about a month ago. On days that I worked, I would just text him a quick note and he responded after he got back from the gym since I had to be at work before he got back from the gym. However, over the past 2 weeks, he has straight up been ignoring my evening calls. I only call once, and you either call me back or don't.
About 2 weeks ago. I mentioned to him that I really enjoy the brief time that I get to talk to him everyday. Normally, I would blow this off, but since it has been going on for more than a few days at this point, I'm starting to get paranoid that he is hiding something. This isn't something I'm going to text to him, I don't want to upset him before he goes in to work during our brief early morning conversation, and since he is not answering my evening calls anymore...I'm lost and just getting more upset and convinced something is going on. Sorry this is so long, but any ideas or opinions would be greatly appreciated. Thank you.

Re: Male perspective?
It could be any number of things to be honest, ranging from the more likely, that he's stressing out due to work or because stuff is about to get real with you on the verge of delivering to worst case scenario of he's cheating.
You need to have a face to face conversation with the man to address the change, preferably before your water breaks.