Why do I very briefly stop breathing at night as I am falling asleep?

As I am falling asleep, sometimes I will "skip" a breath. It will last for less than a second, and it will happen as I am falling asleep, at the stage of sleep where those dreams of falling and jump waking back up happen. I do not believe it is sleep apnea; I had that as a child from oversized tonsils (now removed) & this is no where near that from what I remember of it, especially because the period of not breathing lasts way under what is normally considered for it. My partner has not noticed any change in my sleeping other than the insomnia I have developed.

My insomnia developed due to my pregnancy, I am about 14 weeks along. This weird breathing thing has happened for at least a couple of months now. It is not my first pregnancy, I had twins almost exactly 2 years ago but did not experience this (although I did have the insomnia). It happens in a weird state of half-consciousness I always enter before I fall asleep due to my insomnia that I've never felt other than when experiencing the insomnia.

It is a very odd sensation and one that I am not concerned about health-wise so I do not think a doctor's visit is necessary especially with everything going around, just pure curiousity but don't really know how to search it. I am curious if there are other things that may cause this besides sleep apnea. I tend to be very interested in how the human body works and it is the only reason I am asking, again no concerns for my baby or I.