Ultrahuman's smart ring adds "medical-grade" cycle tracking – for a price

Ultrahuman announced a major step forward in women’s health tracking by acquiring viO HealthTech, the medical tech company behind the clinically validated OvuSense fertility platform.

Alongside the acquisition, the brand is launching Cycle & Ovulation Pro, a paid plug-in for the Ultrahuman Ring AIR that promises the most accurate ovulation tracking available on a smart ring with "over 90%" accuracy.

The feature doesn't assume a standard 28-day cycle and supports irregular cycles and common conditions like PCOS, endometriosis, or thyroid disorders.

The underlying tech is adapted from viO’s OvuSense platform, which is a class II medical device cleared by the FDA and validated in 13 clinical studies.

That same algorithm has been reengineered to work passively through the finger via Ultrahuman’s wearable, meaning you don't need any invasive sensors to gain better insights.

The Pro plugin uses a combination of temperature data and pattern recognition to deliver insights like early or late ovulation, short luteal phases, and even proprietary signals that could indicate issues like missed ovulation or miscarriage risk.

Users can also tag symptoms, moods, and lifestyle factors, making the plugin a genuinely useful long-term wellness tool.

Troubled waters

The announcement comes at a peculiar time when companies like Whoop are battling the FDA over wellness features that the regulatory body deems misleadingly medical.

With wearables getting more and more sophisticated, it's getting increasingly difficult to draw the line where wellness features end and where medical ones begin.

Ultrahuman's Cycle & Ovulation Pro uses a non-medical smart ring to provide information verified by a medical-grade device.

As a result, no matter how closely it can guess things, the feature will always be a guesstimate, at best.

A clinically-backed edge in a stylish form factor

Ultrahuman CEO Mohit Kumar says the update represents the “most accurate women’s health tool available,” combining 15 years of medical-grade research with “comfort and style.”

It’s a rare move in the wearable world: not just adding features for women, but acquiring the tech and expertise needed to deliver real physiological insights.

For anyone already using the Ultrahuman Ring AIR, or considering making the switch from Oura Ring 4, this is a compelling new reason to wear one.

The new PowerPlug is available now in the US, UK, EU, Australia and Canada, and it’s priced at $3.99/month or $39.99/year.

For users who don’t need the advanced insights, the free Cycle & Ovulation PowerPlug remains available.