≥8 mm
endometrial thickness target for transfer
ERA
personalises transfer timing for 25–30% of patients
Trilaminar
endometrial pattern associated with best outcomes
D9–12
post-transfer beta-hCG blood test timing
FET Cycle Timeline
Phase-by-phase guide to a medicated frozen embryo transfer cycle.
Baseline (Day 1–2)
- →Baseline ultrasound to confirm endometrial lining has shed and ovaries are quiet
- →Blood test: oestradiol, progesterone, LH (confirm suppression if on downregulation)
- →Begin oestrogen supplementation as per protocol (oral, patch, or vaginal)
Lining Development (Day 2–12)
- →Oestrogen builds endometrial lining — target trilaminar pattern ≥8 mm
- →Monitoring ultrasound Day 8–10 to assess lining thickness and pattern
- →Continue all supplements: Vitamin D, omega-3, CoQ10, folate
- →Maintain hydration 2–2.5 L/day — supports endometrial blood flow
- →Acupuncture (if using) — typically 2–3 sessions in the week before transfer
Progesterone Start (Day 12–15)
- →Progesterone begins — this is the most critical timing point
- →Natural FET: progesterone starts after confirmed ovulation (LH surge +1 day)
- →Medicated FET: progesterone starts on a fixed day per clinic protocol
- →ERA-personalised FET: progesterone start adjusted to your specific window
- →Avoid vigorous exercise from progesterone start — focus on gentle walking
Transfer Day
- →Drink 500 ml water 1 hour before transfer — full bladder aids ultrasound guidance
- →Wear comfortable, warm clothing — avoid cold exposure
- →Bring support person if permitted by clinic
- →Ask embryologist: embryo grade, expansion stage, and any observations
- →Post-transfer: rest for 30–60 minutes at clinic, then gentle activity is fine
Two-Week Wait (Day 0–14 post-transfer)
- →Continue all medications as prescribed — do not stop without clinic instruction
- →Gentle walking is fine — avoid high-intensity exercise
- →Maintain hydration and anti-inflammatory diet
- →Blood test (beta-hCG) at Day 9–12 post-transfer depending on clinic protocol
- →Manage psychological stress — cortisol does not prevent implantation but affects wellbeing
Endometrial Support Supplements
Discuss all supplements with your specialist before starting.
Vitamin D3
Target 100–150 nmol/L
Vitamin D receptors on endometrial cells regulate implantation-related gene expression including HOXA10 and LIF
Omega-3 (DHA/EPA)
2 g/day
Reduces endometrial inflammatory cytokines; improves uterine blood flow; supports prostaglandin balance
L-arginine
2–3 g/day
Nitric oxide precursor — improves uterine blood flow and endometrial thickness in thin lining cases
Vitamin E
400–600 IU/day
Antioxidant that protects endometrial cells; some evidence for improving thin endometrium alongside L-arginine
Low-dose aspirin
100 mg/day (practitioner-guided)
Improves uterine blood flow via antiplatelet effect; commonly used in FET protocols for thin lining or recurrent failure
Active folate (methylfolate)
800 mcg–1 mg/day
Required for endometrial decidualisation and early embryo development; methylfolate bypasses MTHFR variants
Your Action Plan
FET Preparation Checklist
0/17 completed
Before Your FET Cycle Begins
Confirm Vitamin D level — supplement to reach 100–150 nmol/L before cycle start
Start omega-3 DHA/EPA 2 g/day if not already taking
Confirm active folate (methylfolate) in prenatal supplement
Ask your clinic about ERA testing if this is a second or subsequent FET
Discuss progesterone type and route with your specialist (oral, vaginal, IM injection)
During Lining Development
Maintain hydration 2–2.5 L/day
Adopt anti-inflammatory diet — avoid alcohol, reduce processed foods
Gentle movement only — walking, yoga, stretching
Prioritise sleep 7–9 hours — melatonin supports endometrial receptivity
Reduce psychological stress — consider acupuncture, meditation, or breathwork
Avoid NSAIDs (ibuprofen) unless prescribed — can impair implantation
Transfer Day & Two-Week Wait
Drink 500 ml water 1 hour before transfer
Continue all prescribed medications without interruption
Gentle walking is safe and beneficial — avoid bed rest
Avoid hot baths, saunas, and extreme temperatures
Do not test early with home pregnancy tests — wait for clinic blood test
Have a plan for the result — both positive and negative outcomes