TY - JOUR

T1 - Winter, spring, summer or fall

T2 - temporal patterns in placenta-mediated pregnancy complications — an exploratory analysis

AU - Jeppegaard, Maria

AU - Rasmussen, Steen C.

AU - Anhøj, Jacob

AU - Krebs, Lone

PY - 2024

Y1 - 2024

N2 - Purpose Placenta-mediated pregnancy complications, like growth restriction and hypertensive disorders, are leading causesof maternal, fetal and neonatal morbidity and mortality in high-income countries. The purpose was to investigate if there is aseasonal variation in placenta-mediated pregnancy complications (small for gestational age, intrauterine growth restriction,preeclampsia, preterm birth and intrauterine fetal death).Methods This is a Danish cohort study including all singleton deliveries at gestational week 22 up to and including week 41conceived from December 2006 to November 2016 (N=555,459). We used statistical process control charts to visualize dataand to test for patterns of non-random variation in data over time for pregnancies with risk factors (BMI, diabetes, in vitrofertilization, maternal age>40 years, primipara, previous caesarean and smoking) and each of the following outcome: fetalgrowth restriction, hypertensive disorders, preterm birth and intrauterine fetal death. The study was approved by the DanishData Protection agency; REG-039-2019.Results We found a seasonal pattern in hypertensive disorders during pregnancy with dips in pregnancies conceived in thefall season and highest risk by conception in the spring and summer season. We found no apparent seasonality in cases ofpreterm delivery, small for gestational age and intrauterine mortality. Individual risk factors (e.g. smoking and obesity) forplacenta-mediated complicated over time were in consistency with the general trends.Conclusions We found a signifcant seasonal variation in the risk of hypertensive disorders of pregnancy with highestrisk by conception in the spring and summer season. This study found no seasonal variation in other placenta-mediatedcomplications.

AB - Purpose Placenta-mediated pregnancy complications, like growth restriction and hypertensive disorders, are leading causesof maternal, fetal and neonatal morbidity and mortality in high-income countries. The purpose was to investigate if there is aseasonal variation in placenta-mediated pregnancy complications (small for gestational age, intrauterine growth restriction,preeclampsia, preterm birth and intrauterine fetal death).Methods This is a Danish cohort study including all singleton deliveries at gestational week 22 up to and including week 41conceived from December 2006 to November 2016 (N=555,459). We used statistical process control charts to visualize dataand to test for patterns of non-random variation in data over time for pregnancies with risk factors (BMI, diabetes, in vitrofertilization, maternal age>40 years, primipara, previous caesarean and smoking) and each of the following outcome: fetalgrowth restriction, hypertensive disorders, preterm birth and intrauterine fetal death. The study was approved by the DanishData Protection agency; REG-039-2019.Results We found a seasonal pattern in hypertensive disorders during pregnancy with dips in pregnancies conceived in thefall season and highest risk by conception in the spring and summer season. We found no apparent seasonality in cases ofpreterm delivery, small for gestational age and intrauterine mortality. Individual risk factors (e.g. smoking and obesity) forplacenta-mediated complicated over time were in consistency with the general trends.Conclusions We found a signifcant seasonal variation in the risk of hypertensive disorders of pregnancy with highestrisk by conception in the spring and summer season. This study found no seasonal variation in other placenta-mediatedcomplications.

U2 - 10.1007/s00404-023-07094-6

DO - 10.1007/s00404-023-07094-6

M3 - Journal article

C2 - 37353564

VL - 309

SP - 1991

EP - 1998

JO - Archives of Gynecology and Obstetrics

JF - Archives of Gynecology and Obstetrics

SN - 0932-0067

IS - 5

ER -