Menstrual Cycle Study

Study for the Development of Biometrics-informed Menstrual Cycle Algorithms

A data collection study to develop algorithms to estimate menstrual cycle phases.

Study Overview

• Status: Completed
• Conditions: Menstruation; Ovulation

• Study Type: Observational
• Enrollment (Actual): 143

Contacts and Locations

Study Locations

• United States
  • California
    • San Diego, California, United States, 92103
      • Artemis Headlands LLC (Artemis Institute for Clinical Research)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Healthy, menstruating individuals between 18 to 42 years of age who meet eligibility criteria from one or more clinical research sites in the United States.

Description

Inclusion:

• Adults who are between 18 - 42 years old at enrollment and menstruate
• Capable of giving informed consent in Spanish or English
• Menstrual cycle lengths between 21- 45 days
• Have tracked menstruation for at least 3 menstrual cycles out of the prior 6 months
• Willing to wear a wrist-worn wearable device continuously for 6 months
• Willing to use an ovulation predictor kit for 6 months
• Willing to report vaccine history
• Owns a smartphone compatible with the study and has access to wi-fi

Exclusion:

• A citizen of the European Union or United Kingdom
• Trying to conceive during the six-month study period
• Have used specific forms of birth control in the 3 months prior to the study or planning on using specific birth control methods during the study duration
• Participant has undergone hormonal treatment in the past 3 months or planning to do so during the study
• Known history of health-related issues that affect their menstrual cycle, history of pelvic radiation, vasomotor symptoms, endometriosis, fibroids, polyps, ovarian cysts or known history of health-related issues that affect the physiology
• Currently (or within the past 3 months) engaged in health impacting behaviors
• Have been breastfeeding or pregnant in the past 6 months prior to the study
• On medications or taking substances that could affect their menstrual cycle or physiology
• Travel frequently such as crossing more than two time zones at least once every 2 weeks
• Have a known sleeping disorder or consistently work night shifts

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
All Participants; Up to 150 participants will be enrolled at one or more clinical research sites in the United States. Participants will be healthy, menstruating individuals between 18 to 42 years of age who meet all eligibility criteria.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Ovulation Day Estimation	The algorithm's estimated ovulation day compared to the reference urinary ovulation predictor kits (OPK).	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Menstruation Day Estimation	The algorithm's estimated menstruation date(s) compared to participants' self-reported menstruation date(s).	6 months

Collaborators and Investigators

• Sponsor: Fitbit LLC
• Investigators: Principal Investigator: Daniel Johnson, DO, Artemis Institute for Clinical Research

Study record dates

Study Major Dates

• Study Start (Actual): July 25, 2023
• Primary Completion (Actual): August 30, 2024
• Study Completion (Actual): August 30, 2024

Study Registration Dates

• First Submitted: August 13, 2023
• First Submitted That Met QC Criteria: August 13, 2023
• First Posted (Actual): August 21, 2023

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: December 17, 2024
• Last Verified: September 1, 2024

More Information

Terms related to this study

• Other Study ID Numbers: GH-FH-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• product manufactured in and exported from the U.S.: No