Repair techniques, symptom and fertility outcomes, niche measurement on ultrasound.
This page is written for clinicians and referrers and is not advice for individual patients. If you are a patient, the plain-language page is Caesarean scar niche .
Each week the literature is searched for new papers on caesarean scar niche, screened to the few that meet the evidence bar, and each one is verified on PubMed before it is summarised. I read every entry and give one verdict: whether the paper changes what I tell patients or do in theatre, supports current practice, or leaves it unchanged. Papers appear here newest first, grouped by the week they were found, with the study design, the main result and its effect size, and the reason for the verdict. Abstracts are not reproduced; the summaries are my own.
Digest of 5 November 2026
Search window 30 October 2026 to 5 November 2026
Hysteroscopic and keyhole niche repair compared: hysteroscopy is shorter and has fewer complications, keyhole leaves a thicker wall, and symptoms and pregnancy do not differ, but they are chosen for different women
Meta-analysis of ten comparative studies (one randomised trial of 30 women, one prospective study, eight retrospective) with 798 women, 361 hysteroscopic and 437 laparoscopic, searched to May 2026.
Finding
Hysteroscopy gave fewer overall complications (2 studies, 200 women; OR 0.24, 95% CI 0.07 to 0.82), a shorter operation (56 minutes less, 21 to 90), less blood loss (38 mL less, 28 to 47), a shorter stay (2.84 days less, 1.75 to 3.93) and lower cost ($1,310 less). Residual myometrial thickness rose less after hysteroscopy (mean difference -2.60 mm, -4.11 to -1.09; 4 studies, 357 women; I2 94%). Abnormal bleeding (OR 1.17, 0.58 to 2.36; 5 studies), pelvic pain, dysmenorrhoea, niche depth and subsequent pregnancy (OR 1.07, 0.52 to 2.18; 4 studies, 164 women) did not differ.
Supports current practiceweak evidence
Consistent with his 3 mm division of labour, and too confounded to move a woman from one operation to the other.
What it means
It fits how he already divides the work: hysteroscopy for 3 mm or more of muscle, which trims and drains but does not thicken, and keyhole repair for a thin wall, which rebuilds it.
Conflicts of interest: No funding statement was found in the full text retrieved.
Reviewed by Mr Jan, .
Digest of 29 October 2026
Search window 23 to 29 October 2026
Monofilament or multifilament suture for closing the womb at caesarean: no difference in spotting four to six years later
Secondary long-term follow-up of a randomised trial of 300 women randomised to monofilament or multifilament absorbable suture for uterine closure at caesarean; 117 (39%) were interviewed 4 to 6 years later (51 monofilament, 66 multifilament) and offered a voluntary transvaginal scan, which 21 had.
Finding
Postmenstrual spotting, the primary outcome, was similar: 23.5% against 22.7%, RR 1.04 (95% CI 0.53 to 2.01); other gynaecological symptoms did not differ. Of 21 scanned, 13 had a niche; niches of 4 mm or more were less frequent with monofilament, RR 0.42 (0.18 to 0.97), and a subsequent pregnancy was more frequent with monofilament (29.4% against 12.1%, RR 2.43, 1.12 to 5.27). The authors call these secondary differences exploratory.
No changeweak evidence
Long-term symptoms were the same with either suture, and the niche and pregnancy differences come from very small, exploratory subgroups.
What it means
Suture material does not seem to change long-term spotting after a caesarean, and the hint that monofilament leaves fewer large niches rests on 21 scans.
Conflicts of interest: Funding is not stated in the abstract.
Reviewed by Mr Jan, .
Review of surgical causes of a caesarean scar niche: no technique proven, and a call for screening that the evidence does not support
Systematic review of surgery-related factors in niche formation after caesarean: number of suture layers, locked or unlocked closure, inclusion of the endometrium and suture material.
Finding
Most studies show no superiority of single- or double-layer closure for niche incidence; the authors conclude that optimising hysterotomy technique may reduce niches and their complications, and that all women having a caesarean should be screened for a niche and told of its possible complications.
No changeweak evidence
No new evidence on technique, and the screening recommendation is unsupported.
What it means
It confirms that no closure technique has been shown to prevent a niche.
Conflicts of interest: Funding is not stated in the abstract.
Reviewed by Mr Jan, .
Barbed or monofilament closure at a first caesarean: no clear difference in later conception or pregnancy outcomes
Retrospective single-centre matched cohort at a university hospital in Genoa: 486 women with at least 36 months of follow-up after a primary term caesarean, 162 with continuous unlocked double-layer barbed closure matched 1:2 to 324 with monofilament closure, with outcomes from records and structured interviews.
Finding
Of 205 women trying to conceive, 62 of 73 (84.9%) after barbed and 114 of 132 (86.4%) after monofilament closure conceived; median time to conception 11 against 9 months, adjusted HR 0.72 (95% CI 0.39 to 1.31). Live birth and the outcomes of 148 later deliveries showed no consistent difference; placental and scar complications were too rare to compare.
No changeweak evidence
No clear difference, and the design cannot establish safety.
What it means
Barbed closure at caesarean does not appear to harm later fertility, but the study cannot say it is as safe for the scar.
Conflicts of interest: Funding is not stated in the abstract.
Reviewed by Mr Jan, .
Hormone treatment after niche repair: about one in four women stopped early because of side effects
Retrospective single-centre cohort in Germany of 74 women who had laparoscopic-assisted caesarean scar repair in 2020 to 2023 and were advised temporary progestin (desogestrel, dienogest or unspecified) to suppress periods while the scar healed; 70 answered a questionnaire in 2024.
Finding
Of women with treatment information, 43 of 55 (78.2%) started the progestin; 15 of 61 (24.6%) stopped early because of side effects and 15 of 64 (23.4%) had vaginal bleeding lasting more than 14 days. Mean side-effect intensity was 3.43 (SD 2.99) out of 10; fatigue, irritability and low mood were the most common. Whether the treatment improves healing is unknown.
No changeweak evidence
It describes side effects of a treatment with no proven benefit for healing, which supports not adding it routinely.
What it means
Where hormone suppression is used after a keyhole niche repair, women can be told that about one in four stop early because of side effects and about one in four have prolonged bleeding, and that no study shows it helps the scar heal.
Conflicts of interest: Funding is not stated in the abstract.
Reviewed by Mr Jan, .
Every paper on this site's evidence pages is also available as open data at /evidence/papers.json. The search and screening rules are on the evidence index.
Last reviewed .Reviewed by Mr Haider Jan, Consultant Gynaecologist.
For patients: Caesarean scar niche
The plain-language page on what the condition is, how I assess it and the choices, written for the women I see.
