Background: Climate change with global warming and frequent extreme summer heat could
negagatuively impact pregnancy outcome, but it is still not well understood.

Objective: To assess the association between ambient temperatures of the last 4 weeks of
pregnancy with higher risk for preterm stillbirth.

Material and Methods: Study included all pregnant women with preterm stillbirth (20 to 37
weeks of gestation) treated in the Clinic for Ob/Gyn University Clinical Center of Serbia
durig a ten-year period (2010 to 2019). We used meteorological data (minimal, mean and
maximal temperatures) per year and month for the city of Belgrade which are provided by
Republic Hydrometeorological Sociate yof Sebia and are freely available.
Results: During the study period 409 stillbirths occurred in our Clinic (1.02% of all
deliveries). Gestational week of stilbirth ranged from 18 to 33 (mean +/- SD = 23.8 +/- 2.9).
Mean temperatures ranged from -3.3C (January 2017) to 27 (July 2012). Rates of stillbirths
were simmilar in spring and summer compared to autumn and winter months (233 vs. 186;
p=0.317) as well as if temperatures were <15C and ≥15C (200 vs. 209, p=0.854). Moreover,
there was no trend in stilbirths rates in regards to ambient temepratures of the last 4 weeks of
pregnancy (p=0.435).

Conclusion: Risk for preterm stillbirth was not associated with ambient temperatures of the
last 4 weeks of pregnancy.