I’ve tried ŌURA x Natural Cycles, but when I switched to iPhone earlier this year (yes, again), I was excited to only wear the Apple Watch instead of having a fitness watch and a ring like I did when I was on Android.

So what was my experience like with the Apple Watch and Natural Cycles for ovulation confirmation?

As always with a new method for temperature measurement, I didn’t expect the first few cycles to be of any use, but on the other hand, Natural Cycles has nearly 2 years of data, so I hoped it might perform a little better than it actually did.

Cycle 1

Temperatures were all whackadoo with this cycle. It was actually a bit distressing.

I got a positive LH test on CD 17, so I thought I could call it on CD 19 or so, but temperatures in Natural Cycles had no discernible pattern, which is unusual for me.

If we look at the same cycle in Apple Health (above), the temperatures look a little less wild, but more importantly, Apple Health confirmed ovulation on CD 18, which is around what I would have guessed based on LH.

I figured this was the first cycle, so maybe the next cycle would be better.

Cycle 2

The Natural Cycles app suggested that I switch from wearing my watch on the outside of my wrist (like I normally do) to inside of the wrist just when I sleep. They claim this gives more stable temperatures.

I tried it, and that was definitely my experience. But I still didn’t get a confirmation of ovulation on this cycle!

This sure looked like a shift to me, so I’m not sure why Natural Cycles didn’t mark this as confirmed. Based on the temperatures and the cervical mucus pattern (not shown in this graph), I called this one confirmed at CD 16.

The Apple Health graph mirrored the Natural Cycles graph but seemed to more or less agree with me, showing ovulation occurred on CD 17.

I have a couple guesses why Natural Cycles didn’t mark this ovulation as confirmed.

• Theory 1: The temperature shift wasn’t drastic enough to be considered a “real” shift.
• Theory 2: I didn’t get a positive LH test.

It could also be both of these factors. I was also traveling this cycle, so that could have had something to do with it.

But again, Apple Health had no problem identifying my ovulation day on CD 17, so it was frustrating that Natural Cycles didn’t seem to be doing its job.

When I first saw this, I thought perhaps my cycle and temperatures are changing due to my age, though it’s a bit too early for that. But with the next two cycles, that doesn’t seem to be the case for now.

Cycle 3

I didn’t realize how stressed I was about having unconfirmed ovulations until I got a confirmation this cycle.

The weird thing is, it doesn’t look like the temperatures had a proper shift, and I didn’t get a positive LH on this cycle either. If I ovulated when Natural Cycles says I did, then I missed the optimal time for taking an LH test, so that would explain the negative LH tests.

This isn’t the only cycle that has a confirmation for ovulation without having a clear shift, but that negates my first theory on why I didn’t get a confirmation on Cycle 2 (above).

Apple Health’s ovulation confirmation is on CD 20, which is a day after Natural Cycles, but they’re still close enough.

It’s still weird that they confirm ovulation without a visible temperature shift, but I guess that’s what I’m paying for, right?

Cycle 4

I wasn’t planning to included a fourth cycle in this post, but a cycle managed to fly by while I procrastinated editing this post, so here’s an extra, just for fun.

Natural cycles confirmed ovulation on CD 17, but only after I marked my period for the next cycle. Before that, Natural Cycles guessed ovulation occurred between CD 14 and 20, which is a huge window.

Apple Health shows ovulation on CD 15, which is more in line with cervical mucus, although technically cervical mucus could dry up a day or two before ovulation.

Closing thoughts

I’m going to keep using Natural Cycles, but it’s pretty annoying to not feel confident in the temperatures or algorithm. For years I measured waking temperature orally, and somehow I was more confident back then than now, when I’m using an algorithm and smart device to measure.

Also, wearing the Apple Watch on the inside of my wrist as Natural Cycles suggests is actually uncomfortable. The watch has to be pretty snug so it has adequate contact for measurements and doesn’t slide around, but because of that, it presses against the nerve there, and it gets consistently uncomfortable for me.

We’re using different birth control now, but if we were still fully relying on this method for that, I probably would switch back to the ŌURA ring since I couldn’t place my confidence in these temperatures or algorithm. Tracking cervical mucus has always been part of tracking for me, so that helps, but it doesn’t feel like enough.

More in the Natural Cycles series

First Impressions of the Natural Cycles App

Is ŌURA x Natural Cycles worth it?

ŌURA x Natural Cycles Review: How does it compare to fertility awareness charting?

Temp Tech Showdown: How do Apple Watch Series 8, ŌURA x Natural Cycles, and oral temping compare for fertility awareness?

What happened in Natural Cycles when my ŌURA battery failed?

More about the menstrual cycle

Phases of the Menstrual Cycle

What does temperature have to do with ovulation?

---

Resources and links

This content may contain affiliate links for products I use and believe in. If you subscribe or make a purchase after clicking one of these links, I’ll earn some money at no extra cost to you. I deeply appreciate your support so I can keep doing what I love — providing helpful content to readers like you! Thank you!