Pregnancy Conditions Associated with Delayed Villous Maturation in Placenta: A Systematic Review and Meta-Analysis
Bibliographic record
Abstract
Background Delayed villous maturation (DVM) also called DVI (distal villous immaturity) is a placental maturation disorder that mainly affects maternal-to-fetal oxygen transfer. Objective We conducted a systematic review and meta-analysis of conditions associated with histopathological findings of DVM based on pathologist assessment after delivery. Search strategy Medline, EMBASE, Web of Science, and MIDIRS databases were searched from inception to December 2023. Selection criteria Peer-reviewed, observational studies including cohort, case-control, and cross-sectional studies reported the histopathological findings of DVM after placenta delivery. Data collection and analysis Two reviewers performed the systematic article screening, bias assessment, and data extraction. Senior authors resolved disagreement between reviewers. The risk of bias scoring was assessed using the Newcastle-Ottawa scale for cohort and case-control studies. The random-effect model was used for meta-analysis since there was clinical and statistical heterogeneity ( I 2 ) across studies. For comparisons with an I 2 value < 50% (low heterogeneity), the fixed-effect model was used. Main result There were 52 included studies considered eligible that reported DVM and linked pregnancy conditions. The conditions associated with DVM in term placentas were gestational diabetes (GDM) [OR(95%CI)=3.75(1.93, 7.29)], pregestational diabetes (PGDM) [OR(95%CI)=2.64(1.65, 4.22)], obesity [OR(95%CI)=1.91 (1.23, 2.98)], stillbirth [OR(95%CI)=5.46 (2.26, 13.20)], preterm birth [OR(95%CI)= 3.48 (1.11, 10.97)], and congenital anomalies [OR(95%CI)= 7.57 (3.91, 14.65)]. Conclusion DVM is a placental abnormality associated with dysmetabolism, particularly pregnancy diabetes, and obesity; and with adverse outcomes including stillbirth and congenital anomalies. In studies with variable DVM definition, it was also associated with preterm birth. Optimising metabolism could avoid preventable harm to the baby.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.011 | 0.032 |
| Meta-epidemiology (narrow) | 0.002 | 0.001 |
| Meta-epidemiology (broad) | 0.017 | 0.030 |
| Bibliometrics | 0.008 | 0.008 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.003 | 0.002 |
| Open science | 0.002 | 0.002 |
| Research integrity | 0.002 | 0.002 |
| Insufficient payload (model declined to judge) | 0.004 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".