Talk:Abnormal Development - Maternal Hyperthermia
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Cite this page: Hill, M.A. (2021, July 26) Embryology Abnormal Development - Maternal Hyperthermia. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Abnormal_Development_-_Maternal_Hyperthermia
Sass L, Urhoj SK, Kjærgaard J, Dreier JW, Strandberg-Larsen K & Nybo Andersen AM. (2017). Fever in pregnancy and the risk of congenital malformations: a cohort study. BMC Pregnancy Childbirth , 17, 413. PMID: 29221468 DOI.
Fever in pregnancy and the risk of congenital malformations: a cohort study.
Abstract BACKGROUND: In a variety of animal species, hyperthermia in pregnancy has been recognized as teratogenic. Hyperthermia interferes with protein synthesis via heat-shock proteins, which can entail membrane disruption, cell death, vascular disruption, and placental infarction. This can induce severe fetal malformations or death. Fever during pregnancy, especially during embryogenesis, has also been associated with congenital malformations in human offspring. The purpose of this large cohort study of clinically recognized pregnancies was to investigate whether fever during first trimester was associated with an increased risk of congenital malformations in the offspring. METHODS: The Danish National Birth Cohort is a population-based cohort of 100,418 pregnant women and their offspring recruited in 1996 to 2002. Information on fever during pregnancy was collected prospectively by means of two telephone interviews. The study population comprised the 77,344 pregnancies enrolled in the Danish National Birth Cohort where self-reported information on fever during first trimester of pregnancy was available. Pregnancy outcomes were identified through linkage with the National Patient Registry. Congenital malformations within the first three and a half years of life were categorized according to EUROCAT's classification criteria. Logistic regression models were used to estimate the associations between fever in first trimester and overall congenital malformations and congenital malformations by subgroups. RESULTS: Eight thousand three hundred twenty-one women reported fever during first trimester (10.8%) and 2876 infants were diagnosed with a congenital malformation (3.7%). Fever during first trimester did not affect the risk of overall fetal congenital malformation (OR 0.99, 95% CI 0.88-1.12). The subgroup analyses indicated slightly higher risk of congenital anomalies in the eye, ear, face and neck (OR 1.29, 95% CI 0.78-2.12) and in the genitals (OR 1.17, 95% CI 0.79-1.12), whereas lower risk of malformations in the nervous system (OR 0.47, 95% CI 0.21-1.08), the respiratory system (OR 0.56, 95% CI 0.23-1.29) and in the urinary subgroup (OR 0.58, 95% CI 0.35-0.99) was suggested, the latter constituting the only statistically significant finding. CONCLUSIONS: Overall, this study did not show any association between maternal fever in pregnancy and risk of congenital anomalies. KEYWORDS: Congenital anomalies; Congenital malformations; Fever; Hyperthermia; Pregnancy PMID: 29221468 PMCID: PMC5723098 DOI: 10.1186/s12884-017-1585-0
Climate extremes and the length of gestation
Environ Health Perspect. 2011 Oct;119(10):1449-53. Epub 2011 Jun 9.
Dadvand P, Basagaña X, Sartini C, Figueras F, Vrijheid M, de Nazelle A, Sunyer J, Nieuwenhuijsen MJ. Source Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain. email@example.com
BACKGROUND: Although future climate is predicted to have more extreme heat conditions, the available evidence on the impact of these conditions on pregnancy length is very scarce and inconclusive.Objectives: We investigated the impact of maternal short-term exposure to extreme ambient heat on the length of pregnancy. METHODS: This study was based on a cohort of births that occurred in a major university hospital in Barcelona during 2001-2005. Three indicators of extreme heat conditions based on 1-day exposure to an unusually high heat-humidity index were applied. Each mother was assigned the measures made by the meteorological station closest to maternal residential postcodes. A two-stage analysis was developed to quantify the change in pregnancy length after maternal exposure to extreme heat conditions adjusted for a range of covariates. The second step was repeated for lags 0 (delivery date) to 6 days. RESULTS: We included data from 7,585 pregnant women in our analysis. We estimated a 5-day reduction in average gestational age at delivery after an unusually high heat-humidity index on the day before delivery. CONCLUSION: Extreme heat was associated with a reduction in the average gestational age of children delivered the next day, suggesting an immediate effect of this exposure on pregnant women. Further studies are required to confirm our findings in different settings. Comment in Environ Health Perspect. 2011 Oct;119(10):A443.
Environ Health Perspect. 2011 Oct;119(10):A443.
Pregnancy tends to make women more vulnerable to heat stress. Added fat deposits and the attendant decrease in the ratio of body surface area to body mass mean a woman’s body is less able to cool off by losing heat to the environment. Heat stress has been linked in earlier studies to induction of uterine contractions, increased secretion of the childbirth-related hormones oxytocin and prostaglandin F2, and increased levels of heat-shock protein 70 (which has been linked to preterm delivery). A new study now suggests maternal exposure to extreme heat may have an immediate effect on pregnancy duration [EHP 119(10):1449–1453; Dadvand et al.].
Comment on Environ Health Perspect. 2011 Oct;119(10):1449-53.