EGU25-19569, updated on 15 Mar 2025
https://doi.org/10.5194/egusphere-egu25-19569
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
The influence of transient air pollution exposure on preterm birth: A case-crossover analysis with high spatio-temporal resolution assessment in the Rotterdam-Rijnmond region, The Netherlands 
Medha J Pfaff1, Benjamin Y Gravesteijn2, Nienke W Boderie3, Sef van den Elshout4, Lizbeth Burgos Ochoa5, Loes CM Bertens6, Famke JM Mölenberg1, Fabio Porru7, Alex Burdorf1, and Jasper V Been6,8
Medha J Pfaff et al.
  • 1Erasmus University Medical Center, Department of Public Health, Netherlands (m.pfaff@erasmusmc.nl, f.molenberg@erasmusmc.nl, a.burdorf@erasmusmc.nl))
  • 2University of Amsterdam, Medical Center, Department of Obstetrics and Gynaecology, Netherlands (b.y.gravesteijn@amsterdamumc.nl)
  • 3Public Health Service Brabant, Netherlands (n.boderie@ggdhvb.nl)
  • 4DCMR Environmental Monitoring Service Rijnmond, Department of Air quality, Netherlands (sef.vandenelshout@dcmr.nl)
  • 5Tilburg School of Social and Behavioral Sciences, Department of Methodology, Netherlands (l.burgosochoa@tilburguniversity.edu)
  • 6Erasmus University Medical Center Sophia Children's Hospital, Department of Obstetrics and Gynaecology, Netherlands (l.bertens@erasmusmc.nl, j.been@erasmusmc.nl)
  • 7Erasmus University Rotterdam, Student Wellbeing Project, Netherlands (fabio.porru@eur.nl)
  • 8Erasmus University Medical Center Sophia Children's Hospital, Department of Pediatrics, Netherlands (j.been@erasmusmc.nl)

Background
Air pollution, a leading risk factor for mortality, is linked to adverse birth outcomes, including preterm birth (PTB). This study investigated the association between the transient exposure to three pollutants (Particulate Matter with a diameter < 10 µm (PM10), Nitrogen Dioxide (NO2) and Ozone (O3)) and PTB during the week before delivery. As previous research in the study area mainly investigated chronic or long-term exposure to air pollution and is subject to confounding, the current work presents an important contribution to the literature.

Methods
This case-crossover-study included 13’058 singleton preterm deliveries (< 37 weeks) in the Rotterdam-Rijnmond region, the Netherlands, between 2003 and 2019. Daily averaged pollutant concentrations, derived through dispersion modelling by the local environmental service (DCMR) were spatiotemporally linked to the residence of birth parents. We conducted conditional logistic regression to derive odds ratios (ORs) and 95% confidence intervals (CIs) for the association between an interquartile range (IQR) increase in pollutants and PTB across individual lag days. Moreover, we performed subset analyses based on season (warm vs. cold), socioeconomic status (SES; lowest vs. highest quintile) and spontaneous PTB cases only.

Results
During the warm season (May-October), an interquartile range (IQR) increase in O3 was linked to a 3%, respectively 4%, rise in the odds of preterm birth (PTB) on the two days preceding delivery, for the general study population and the spontaneous PTB subgroup. For the low-SES subset, increased odds of PTB were observed by 9% on lag day 6 (ORlag6 1.09, 95% CI 1.02 -1.16).
In the cold season (November-April), an IQR increase in NO2 was associated with a 4-10% increase in PTB odds during the week before birth, peaking around lag days 1 and 2 (ORlag1 1.10, 95% CI 1.05-1.15; ORlag2 1.10, 95% CI 1.06-1.15). Meanwhile, the low-SES subgroup saw a 10% rise during the three days preceding delivery (ORlag1-3 1.10, 95% CI 1.00 – 1.19), whereas for the spontaneous PTB subgroup, a rise of 6% was found at lag6 (ORlag6 1.06, 95% CI 1.00, 1.12). Similarly to ozone, PM10 was associated with a slight increase in odds of 3% close to the delivery date (ORlag0-1 1.03, 95% CI 1.00, 1.06). No significant findings were derived for the subset analyses.  

Conclusion
The results suggest that short-term exposure to all three pollutants is associated with increased risk of PTB. Furthermore, the findings point to the heightened vulnerability of the low-SES and spontaneous PTB subgroups, despite their relatively small sample size. With the high spatiotemporal resolution of the utilized air quality data and the robust case-crossover design underlining the validity of the results, future studies should ideally incorporate information about time of onset of labor and indoor air quality data to tackle potential issues of non-differential exposure misclassification.  

How to cite: Pfaff, M. J., Gravesteijn, B. Y., Boderie, N. W., van den Elshout, S., Burgos Ochoa, L., Bertens, L. C., Mölenberg, F. J., Porru, F., Burdorf, A., and Been, J. V.: The influence of transient air pollution exposure on preterm birth: A case-crossover analysis with high spatio-temporal resolution assessment in the Rotterdam-Rijnmond region, The Netherlands , EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-19569, https://doi.org/10.5194/egusphere-egu25-19569, 2025.

Corresponding supplementary materials formerly uploaded have been withdrawn.