Stimulation cycle dates calculator
Generates an approximate schedule for an IVF stimulation cycle — from cycle programming through gonadotrophin stimulation, trigger and egg collection. Supports a GnRH antagonist protocol (optionally Norethisterone-programmed, as in the FET calculator) and a long GnRH agonist protocol. All intervals are adjustable; exact dates follow your clinic’s protocol.
Inputs
Schedule
| Date | Cycle day | Action |
|---|
Methods
Dates in the treatment cycle are counted by cycle day (cycle day 1 = the first day of the period). In the antagonist protocol the cycle may be programmed with Norethisterone (day 14–25 of Cycle 1, with a withdrawal bleed ~3 days after stopping marking Cycle 2 day 1) or started directly from the first day of the Cycle 2 period. A baseline scan and gonadotrophin stimulation begin on about cycle day 3, monitoring ultrasound scans follow on cycle days 6, 8, 10 and 12, a GnRH antagonist is added from about cycle day 7–9 (or when the lead follicle reaches ~14 mm), the trigger is given once follicles are mature (around cycle day 12–14), and egg collection follows ~36 hours later. In the long agonist protocol the cycle is usually programmed with Norethisterone (day 14–25 of Cycle 1); a GnRH agonist is started in the mid-luteal phase (~day 21), and once downregulation is confirmed (~11 days) the baseline scan and gonadotrophin stimulation begin alongside the agonist, with the same monitoring, trigger and egg-collection pattern. A fresh Day-5 blastocyst transfer, if performed, is about 5 days after egg collection. Cycle days and intervals are idealised and vary between clinics and patients.