Should o be concerned?

SO left his phone open on the bathroom counter this morning when we went for work. He texted a co worked asking if she worked today. She then replied "how are you gorgeous" and then "have i ever had you over to my house". He replied to her "no i have never been". I am pretty concerned about the way she is talking to him. Do i bring it up to him? I think he will be irritated i was snooping. I want to text her and ask whh shes calling him gorgeous and basically inviting him over imo. I am 7 months pregnant and it has been rough us lately. What do you think i should do ???😭