Knowledge Library
REI#rei#hcg#early-pregnancyPGY 2/3/4

HCG Trending Rules

When to repeat, when to scan, IVF-specific rules. Use cases: ectopic, anticoagulated, RPL, inappropriate rise.

Source: REI PGY-2 handoff

  • If second HCG and appropriate rise (double every 2 days) → OB ultrasound at 6–7 weeks.
  • If hx ectopic, anticoagulation, or RPL → OB U/S at 5 weeks.
  • If inappropriate HCG rise → repeat HCG in 2 days (if going into weekend, repeat in 4 days).

For IVF (April 2026 update: did not need to present these):

  • 2w5d pregnant at day of transfer of embryo (even if embryo growth until day 7, because embryos are held to day 5 criteria to be appropriate for implantation).
  • Power statement: include blastocyst status (e.g., diploid, if was programed).
Tip: Get the Ferring app on your phone (free). Use to determine gestational age for IUI.

Referenced by handoffs