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Proposed Algorithm Changes (Pregnancy Configuration)

Audience: algorithm authors and clinical collaborators. This summarizes proposed behavior changes based on the pregnancy protocol and current device plan (OmniPod DASH + Dexcom G7). It is intentionally non‑technical.

Summary

The pregnancy configuration keeps the core algorithm structure intact, but shifts glucose targets lower and increases meal dosing aggressiveness. These changes aim to improve pregnancy‑specific time‑in‑range while maintaining safety through alarms and fallback behavior.

Proposed Changes vs. Standard Configuration

1) Lower glucose targets - Add lower target options centered around 90 mg/dL and 100 mg/dL (in addition to the usual 110/120/130 mg/dL targets). - These lower targets are the primary pregnancy‑configuration change.

2) Meal dosing fraction increased - Increase the meal controller fraction from ~75% of learned meal requirement to ~90%. - Rationale: more aggressive post‑meal control during pregnancy while still avoiding full correction‑style dosing.

3) Unchanged core algorithm structure - No new controllers or major structural changes are proposed. - The algorithm still adapts continuously based on observed glucose and insulin use. - The default insulin action time (tmax) remains 65 minutes (fixed).

4) CGM downtime behavior retained - If CGM is unavailable, allow fingerstick BG as CGM input. - Basal fallback uses weight‑based dosing early, then adaptive basal after sufficient history (>= 24 hours).

Operational Context (Non‑Algorithm)

These are delivery‑system behaviors to support safe operation but are not algorithm changes: - Offline mode: if no valid CGM + algorithm run for ≥ 15 minutes, fall back to a predefined basal on the pump and notify the user. - When CGM resumes, algorithm outputs immediately override offline basal. - Device integration is via Dexcom G7 and OmniPod DASH (no Beta Bionics hardware).

Open Questions for Review

  • Are the 90/100 mg/dL targets and 90% meal fraction sufficient, or should additional safety limits be added for specific gestational stages?
  • Should meal fraction vary by meal type (breakfast vs. dinner) or remain uniform?
  • Are additional safeguards needed during rapid insulin‑resistance changes in late pregnancy?

Status

These are proposed changes derived from the pregnancy protocol and have not been finalized or validated in clinical use within this app.