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 twelve 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 that the prevalence of abnormal findings after two losses is broadly similar to that after three — so waiting for a third loss delays diagnosis without improving yield. That is the evidence base for the lower threshold.^[6]

The terminology you should be using. The ESHRE early-pregnancy consensus set the vocabulary: pregnancy of unknown location, biochemical pregnancy loss, clinical miscarriage — and C-Gyn 38 asks you to abandon spontaneous abortion, biochemical pregnancy and blighted ovum. Primary recurrent loss means no previous live birth; secondary means a loss series after one.^[1][5]

References20ShowHide

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
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