Recurrent pregnancy loss

She has brought a folder. Inside are three ultrasound reports, a printed list of tests she found online, and a question she has asked two doctors already: "Why does this keep happening?" She is 34, she has had three losses, and the last clinician told her to come back after the next one. The fellowship-level answer is not a longer test list. It is knowing which four tests are worth doing, which tests are worth refusing, and how to say both without dismissing her.^[1][4]

Overview and definition — the change that matters

The threshold moved, and the exam has moved with it. ^[1][2]

• ESHRE: recurrent pregnancy loss is the loss of two or more pregnancies, excluding ectopic and molar pregnancy. The 2023 update reviewed 1419 new papers and found no evidence to revise it.^[1]
• RANZCOG C-Gyn 38 (Version 1, March 2025): two or more intrauterine losses up to 20 weeks, whether or not a gestational sac was seen and whether or not the losses were consecutive — with the term reserved for losses confirmed as intrauterine.^[1][2]
• RCOG Green-top 17 (2023): retains a three-loss framing in its title population. Name the difference at the station rather than pretending it does not exist.^[2]

Why the number matters clinically, not just semantically. Systematic review found abnormal findings for uterine anomalies and antiphospholipid syndrome are no different after two losses than three — with less certainty for chromosomal, thrombophilia and thyroid testing — so waiting for a third loss delays diagnosis without clear gain. That is the evidence base for the lower threshold.^[6]

The terminology you should be using. The ESHRE early-pregnancy consensus set the vocabulary from clinical findings and transvaginal ultrasound — and C-Gyn 38 asks you to abandon spontaneous abortion, biochemical pregnancy and blighted ovum. Name each loss by what was seen, not by a folk term.^[1][21]

References21ShowHide

1. [1]Bender Atik R, Christiansen OB, Elson J, et al. ESHRE guideline: recurrent pregnancy loss: an update in 2022 Hum Reprod Open, 2023.PMID 36873081
2. [2]Regan L, Rai R, Saravelos S, Li TC; Royal College of Obstetricians and Gynaecologists Recurrent MiscarriageGreen-top Guideline No. 17 BJOG, 2023.PMID 37334488
3. [3]Coomarasamy A, Dhillon-Smith RK, Papadopoulou A, et al. Recurrent miscarriage: evidence to accelerate action Lancet, 2021.PMID 33915096
4. [4]Quenby S, Gallos ID, Dhillon-Smith RK, et al. Miscarriage matters: the epidemiological, physical, psychological, and economic costs of early pregnancy loss Lancet, 2021.PMID 33915094
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12. [13]Dhillon-Smith RK, Middleton LJ, Sunner KK, et al. Levothyroxine in Women with Thyroid Peroxidase Antibodies before Conception N Engl J Med, 2019.PMID 30907987
13. [14]Chan YY, Jayaprakasan K, Zamora J, et al. The prevalence of congenital uterine anomalies in unselected and high-risk populations: a systematic review Hum Reprod Update, 2011.PMID 21705770
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19. [20]Farren J, Jalmbrant M, Falconieri N, et al. Posttraumatic stress, anxiety and depression following miscarriage and ectopic pregnancy: a multicenter, prospective, cohort study Am J Obstet Gynecol, 2020.PMID 31953115
20. [21]Royal Australian and New Zealand College of Obstetricians and Gynaecologists. Miscarriage, Recurrent Miscarriage and Ectopic Pregnancy (C-Gyn 38), Clinical Guideline, Version 1. RANZCOG, 2025.Source
21. [22]Doyle AJ, Cox C, Breen KA Antiphospholipid syndrome and pregnancy-a hematologic perspective. Res Pract Thromb Haemost, 2026.PMID 41890553