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IVF Embryo and Gestational Sac Size Variation at Different Gestations According to Embryo Transfer Date
Sughashini Murugesu1, Amy Shearer, Kristofer Linton-Reid
1Queen Charlotte's and Chelsea Hospital (S.M., A.S., D.B., M.M., C.S., S.S., S.S., T.B.), Department of Metabolism, Digestion and Reproduction (S.M., S.S., T.B.), and Department of Cancer and Surgery (K.L.-R., E.O.A.), Imperial College, London, United Kingdom; and Department of Obstetrics and Gynaecology, University Hospitals Leuven, Leuven, Belgium (T.B.).
Diagnosing miscarriage requires specific ultrasound measurements. Current guidelines suggest repeat scans at 7-14 days to confirm diagnosis and avoid false positives.
Area of Science:
- Reproductive Medicine
- Obstetrics and Gynecology
- Diagnostic Imaging
Background:
- Current Royal College of Obstetricians and Gynecologists guidelines define miscarriage diagnosis using transvaginal ultrasound criteria.
- These criteria include an empty gestational sac ≥25 mm or an embryo with crown-rump length (CRL) ≥7 mm without a heartbeat.
- National Institute for Health and Care Excellence (NICE) guidelines recommend a repeat scan after a minimum of 7 days.
Purpose of the Study:
- To review and synthesize current evidence regarding the optimal timing for repeat ultrasound scans in the diagnosis of miscarriage.
- To evaluate the efficacy of different repeat scan intervals in ruling out false-positive diagnoses.
- To inform clinical practice and guideline development for miscarriage diagnosis.
Main Methods:
- Review of existing clinical guidelines and relevant scientific literature.
- Analysis of evidence supporting different repeat scan intervals (7 days vs. 14 days).
- Examination of diagnostic accuracy and false-positive rates associated with current protocols.
Main Results:
- Evidence suggests a repeat scan at 14 days may be beneficial for diagnosing an empty gestational sac to rule out false positives.
- The optimal interval for repeat scanning requires further investigation to balance diagnostic accuracy with patient management.
- Current guidelines vary on the recommended interval for repeat scans.
Conclusions:
- Confirmation of miscarriage diagnosis using ultrasound requires careful consideration of gestational sac and embryo measurements.
- Repeat ultrasound scans are crucial for accurate diagnosis, with a 14-day interval showing promise for empty sac diagnoses.
- Further research is needed to establish definitive evidence-based recommendations for repeat scan timing in miscarriage diagnosis.
