A randomized trial of web-based fertility-tracking software and fecundability

Area of Science:

• Reproductive Health
• Digital Health Interventions
• Clinical Trials

Background:

• Fertility tracking apps are increasingly used by individuals trying to conceive.
• Understanding the impact of these digital tools on fecundability is crucial for evidence-based reproductive health guidance.
• The Pregnancy Study Online (PRESTO) cohort provides a platform for evaluating preconception interventions.

Purpose of the Study:

• To assess the effect of randomization to the FertilityFriend.com (FF) mobile app on fecundability.
• To evaluate the association between FF app use and the per-cycle probability of conception.

Main Methods:

• A parallel non-blinded randomized controlled trial nested within the PRESTO cohort.
• 5532 female participants aged 21-45 years attempting conception were randomized (1:1) to receive a premium FF subscription.
• Intent-to-treat and per-protocol analyses using proportional probabilities regression models were conducted to estimate fecundability ratios.

Main Results:

• Intent-to-treat analyses showed no appreciable association between FF randomization and overall fecundability (FR = 0.97).
• Per-protocol analyses indicated a slight positive association with fecundability (FR = 1.06), particularly in subgroups like younger women or those with longer conception attempt times.
• Adherence to the FF app was observed in 72% of randomized participants.

Conclusions:

• Randomization to the FF app did not demonstrate a significant impact on overall fecundability in intent-to-treat analyses.
• Secondary per-protocol analyses suggested potential benefits in specific subgroups, but these findings may be influenced by unmeasured confounding factors.