Evidence map›Paper›PMID 41588912›Full record

ArticleBJOG : an international journal of obstetrics and gynaecology2026

Temporal Patterns in Preterm Birth Subtypes and Perinatal Survival, 2000-2023: Population-Based, Repeated Cross-Sectional Time-Series.

Ka Wang Cheung, Tiffany Sin-Tung Au, Tat On Chan, Annie Shuk Yi Hui, Po Lam So, Daniel Wong, Tsz Kin Lo, Wai Lam Lau, Choi Wah Kong, Teresa Wei Ling Ma and 2 more

Abstract read
In one paragraph

Article in BJOG : an international journal of obstetrics and gynaecology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

12 authors.

Ka Wang CheungDepartment of Obstetrics and Gynaecology, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong SAR, China.ORCID https://orcid.org/0000-0003-1207-6494
Tiffany Sin-Tung AuDepartment of Obstetrics and Gynaecology, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong SAR, China.
Tat On ChanDepartment of Obstetrics and Gynaecology, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong SAR, China.
Annie Shuk Yi HuiDepartment of Obstetrics and Gynaecology, Prince of Wales Hospital, the Chinese University of Hong Kong, Hong Kong, Hong Kong SAR, China.
Po Lam SoDepartment of Obstetrics and Gynaecology, Tuen Mun Hospital, Hong Kong, Hong Kong SAR, China.
Daniel WongDepartment of Obstetrics and Gynaecology, Pamela Youde Nethersole Eastern Hospital, Hong Kong, Hong Kong SAR, China.
Tsz Kin LoDepartment of Obstetrics and Gynaecology, Princess Margaret Hospital, Hong Kong, Hong Kong SAR, China.
Wai Lam LauDepartment of Obstetrics and Gynaecology, Kwong Wah Hospital, Hong Kong, Hong Kong SAR, China.
Choi Wah KongDepartment of Obstetrics and Gynaecology, United Christian Hospital, Hong Kong, Hong Kong SAR, China.
Teresa Wei Ling MaDepartment of Obstetrics and Gynaecology, Queen Elizabeth Hospital, Hong Kong, Hong Kong SAR, China.
Ying Rong LiDepartment of Obstetrics and Gynaecology, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong SAR, China.
Mimi Tin-Yan SetoDepartment of Obstetrics and Gynaecology, Queen Mary Hospital, The University of Hong Kong, Hong Kong, Hong Kong SAR, China.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectiveEvaluate the rate and trend of preterm birth (PTB) and the associated perinatal survival in Hong Kong.

designPopulation-based, repeated cross-sectional time series.

settingAll public maternity hospitals. POPULATION: 845 640 singleton and 26 748 twin deliveries from 2000 to 2023.

methodsTwo analyses were performed (i) spontaneous PTB (sPTB) vs. iatrogenic PTB (iPTB), (ii) spontaneous PTB with no preterm prelabour rupture of membranes (PPROM) (sPTB-noPPROM) versus. PTB following PPROM (PTB-PPROM) vs. iPTB.

main outcome measuresPTB rate and perinatal survival.

resultsSimply dividing PTB into sPTB and iPTB demonstrated increasing PTB rates for both types amongst singleton and twin pregnancy. Subclassification of sPTB into sPTB-noPPROM and PTB-PPROM demonstrated a downward trend in sPTB-noPPROM while PTB-PPROM increased significantly (singleton: sPTB-noPPROM average annual percent change (AAPC) -0.96, 95% CI -1.67 to -0.41; PTB-PPROM AAPC 3.4, 95% CI 2.89 to 4.18; iPTB AAPC 2.01, 95% CI 1.57 to 2.45; twin: sPTB-noPPROM AAPC -2.62, 95% CI -4.09 to -1.58; PTB-PPROM AAPC 3.05, 95% CI 2.46 to 3.72; iPTB AAPC 2.75, 95% CI 1.82 to 3.69). PTB-PPROM and iPTB were the leading causes of PTB for singleton and twin pregnancy, respectively. Hypertensive disorders were the predominant causes of iPTB for both singleton and twin pregnancy while iPTB indicated by maternal illnesses reduced over time. Reduction of neonatal mortality rates were noted amongst iPTB for singleton < 37 weeks and twin pregnancies at 34

conclusionsPerinatal survival improved despite increasing PTB rates. The trend of PTB should be interpreted in the context of perinatal health indicators, and categorisation of PTB could aid with truly reflecting and explaining the trends and patterns of PTB within a population.

Indexed as

Perinatal MortalityPremature BirthAdultCross-Sectional StudiesFemaleHong KongHumansInfant, NewbornPregnancyPregnancy, TwinPremature Rupture of Fetal Membraneslow birth weightmortalityprematuritypreterm labourstillbirth

Identifiers

PMID41588912
PMCPMC13040435

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.