Normal AHI (2.4) but elevated RDI (7.3)? CPAP or not?

[sleepysleepsleep]

[color=var(--newCommunityTheme-bodyText)]I’m a 33 year old normal weight woman. Also 31 weeks pregnant. I suspected I might have apnea from my Apple Watch which showed oxygen dips into the high 80s or low 90s at night a few times a week. Finally looked into it recently and did an at home online sleep study (Lofta). They said my AHI is 2.4 (oxygen nadir of 91%) and my RDI is 7.3, and based on my RDI they recommend a cpap. I totally believe them on the RDI front because I recorded myself sleeping one night and I had about 7-8 very deep sighs an hour. [/color]

[color=var(--newCommunityTheme-bodyText)]I wouldn't be surprised if my pregnancy contributes to any of this, but it's worth noting that my Apple watch shows the same pattern of dips even before I got pregnant. 
I want my baby to get as much oxygen as he can during my remaining pregnancy but I’m worried about using a cpap when it’s not totally necessary (saw someone say it can induce central sleep apnea, cause a hypoxic state or barometric trauma to the lungs in people who don’t really need one). Also, if apnea is mostly present during the first few hours of the night would wearing a cpap the rest of the night be necessary? I even bought an actual oximeter and wore it the other night, which showed 8 desaturation events from 1-2 AM but not for the rest of the night. [/color]

[gainerfull]

Based upon your AHI / RDI difference it sounds like you're having quite a few RERAs (respiratory related arousals) which are fragmenting your sleep. If I were you I'd get started with CPAP therapy as soon as feasibly possible however using it only for partial nights is not going to help much.

Your best bet is to acquire a data capable CPAP machine like the Resmed Airsense 10 or Resmed Airsense 11 vAUTO, record your sleep data to an SD card and import it into OSCAR. Once you have a couple of nights you can return here and post the results so members can make recommendations to optimize your therapy.

I also have battled RERAs for a long time and have recently dramatically improved my sleep by switching to constant pressure mode. Also, it's great your apple watch caught your sp02 desaturation but you may consider picking up the Wellue O2 Ring from amazon which can record a full night's sleep and polls more frequently in order to aid in optimizing your therapy.

[Gideon]

[color=var(--newCommunityTheme-bodyText)] but I’m worried about using a cpap when it’s not totally necessary (saw someone say it can induce central sleep apnea, cause a hypoxic state or barometric trauma to the lungs in people who don’t really need one). Also, if apnea is mostly present during the first few hours of the night would wearing a cpap the rest of the night be necessary? I even bought an actual oximeter and wore it the other night, which showed 8 desaturation events from 1-2 AM but not for the rest of the night. [/color]

barametric trauma. unless you have VERY unhealthy lungs you should be ok.  IF that are that bad you already know about it.
Central Sleep Apnea, honestly just the use of a CPAP can cause that.  Our bodies trigger to breath, simply put, come from our need to remove CO2 and byproducts from our body.  CPAP will improve the efficiency of your breathing generally increasing your oxygen sats with the potential of central being caused by removing too much CO2.  These are typically brief and generally not a big deal as your breathing starts up as soon as the CO2 levels rise.

Basicly don't fear these issues as they are manageable. It is not uncommon for pregnant women to need CPAP.