What to Do If You Miss a Dose of 6 mg Oral Estrace During FET
If you miss a dose of your 6 mg oral Estrace during a fully medicated frozen embryo transfer cycle, take the missed dose as soon as you remember and continue your regular schedule, even if this means taking two doses on the same day.
Timing-Based Action Plan
The appropriate response depends on how long it has been since you should have taken your dose:
If Less Than 24 Hours Late
- Take the late dose immediately 1, 2, 3
- Continue taking remaining doses at your usual time (you may take two doses on the same day if needed) 1, 2, 3
- No additional precautions are necessary 4, 1, 2
If 24-48 Hours Late (One Missed Dose)
- Take the most recent missed dose as soon as possible 1, 2, 3
- Discard any other missed doses 4, 1, 2
- Continue your regular schedule at the usual time 1, 2, 3
- Contact your fertility clinic to discuss whether your embryo transfer timing needs adjustment, as maintaining adequate endometrial preparation is critical for FET success 5, 6
If More Than 48 Hours Late (Two or More Missed Doses)
- Take the most recent missed dose immediately 1, 2, 3
- Discard other missed doses 4, 1, 2
- Contact your fertility clinic immediately before proceeding, as significant gaps in estrogen supplementation may compromise endometrial thickness and receptivity 5, 7
Important Context for FET Cycles
Critical distinction: The guidelines cited above 4, 1, 2, 3 are designed for combined oral contraceptives (which contain both estrogen and progestin for contraception), not for estrogen-only protocols used in FET cycles. However, the basic principle of taking missed doses promptly still applies.
Why FET Is Different
- In FET cycles, you are taking estrogen to build and maintain endometrial thickness for embryo implantation, not for contraception 8, 5, 7
- Consistent estrogen levels are essential to maintain adequate endometrial development (typically ≥8 mm thickness) 8, 5
- Research shows that endometrial thickness directly correlates with pregnancy success in FET cycles 5, 7
Key Clinical Considerations
- Studies demonstrate that step-up estrogen regimens (starting lower and increasing) can achieve optimal endometrial thickness of 9-10 mm 5
- Missing doses may result in suboptimal endometrial development, potentially requiring cycle cancellation or delay 8, 5
- Your clinic may need to perform an ultrasound to verify adequate endometrial thickness before proceeding with transfer 8, 5
When to Contact Your Clinic
Always contact your fertility clinic if:
- You have missed more than one dose 5, 6
- You are within 7 days of your scheduled embryo transfer 5
- You experience any unusual bleeding or spotting 1
- You have any concerns about your medication schedule 6
Your clinic may need to check your serum estradiol levels and endometrial thickness via ultrasound to ensure the cycle can proceed safely 5, 7, 6.