Season of birth affects short‐ and long‐term survival

Abstract

Recent research findings have highlighted the importance of early life conditions as risk factors for adult diseases and therefore determinants of subsequent survival. Given that individuals born during different seasons in seasonal environments experience different early-developmental conditions, an analysis of the effects of the season of birth on survival is considered an effective approach in clarifying the influence of early life conditions on survival in later life. In the present study, we analyzed the long-term effects of early developmental conditions in a historical population in which both nutritional levels and the burden of infectious diseases showed a seasonal variation. Using a semi-computerized linkage process, we were able to match birth and death data for 4,646 individuals born between 1634 and 1870 in the village of Es Mercadal (Minorca Island, Spain). To determine ecological differences associated with the season of birth, we first evaluated the association between season of birth and early life survival. This analysis helped us to determine seasonal variations in early life conditions such as infectious burden and nutritional levels. The season of birth had a significant effect on long-term survival in the birth cohort 1800-1870: summer births had a lower risk of death after age 15. We explain these results in terms of lower susceptibility to degenerative diseases in adult years due to superior in utero nutrition for summer births. These findings support the fetal origin hypothesis which states that the early life environment plays a key role in shaping the subsequent phenotype and risk of adult disease.

Is Cardiovascular Mortality Related to the Season of Birth?

“…Of note, the latter finding excludes that differing death rates throughout the months of the year are the basis for the observed relationship solely due to arithmetical reasons. The observations parallel other investigations demonstrating a statistically significant relationship between season of birth and survival from all causes, even if the seasonal distribution is not consistent in all of these studies (5,6).…”

Prenatal factors associated with the neonatal line thickness in human deciduous incisors

“…This influence concerns many biological features, among others: fecundity, conceptions and births (Leslie and Fry, 1989;Lam et al, 1994;Malina and Himes, 1977;Panter-Brick, 1996), sex ratio at birth (Nonaka et al, 1999), children's birth parameters (McGrath et al, 2005), infant mortality (Doblhammer and Vaupel, 2001), adult mortality (Moore et al, 1997), height and weight in later life (Banegas et al, 2001;Henneberg and Louw, 1993;Kościński et al, 2004;Krenz-Niedbała et al, 2011;Shephard et al, 1979;Weber et al, 1998), cardiovascular conditions in adulthood (Doblhammer and Vaupel, 2001;Painter et al, 2005), life expectancy and the probability of death at older ages (Doblhammer and Vaupel, 2001;Gagnon, 2012;Muñoz-Tudurí and García-Moro, 2008), and even the incidence of certain neurodegenerative diseases, such as multiple sclerosis (Doblhammer et al, 2005; G Model JCHB-25372; No. of Pages 13 Salzer et al, 2010;Wiberg and Templer, 1994;Willer et al, 2005) or Parkinson's disease (Gardener et al, 2010;Mattock et al, 1988).…”

Season of birth and the risk of type 2 diabetes in adulthood: a prospective cohort study of 0.5 million Chinese adults

“…Factors exhibiting seasonal variation include, but are not limited to, exposure to sunlight, food availability and eating habits, and outdoor physical activity [4][5][6][7][8]. Only a few studies conducted in white populations living in relatively high-latitude regions have examined the association between the season or month of birth and type 2 diabetes in adulthood, with mixed results [9][10][11].…”