The impact of the Wenchuan earthquake on early puberty: a natural experiment

Abstract

BackgroundThe factors influencing pubertal timing have gained much attention due to a secular trend toward earlier pubertal onset in many countries. However, no studies have investigated the association between the Great earthquake and early puberty. We aimed to assess whether the Wenchuan earthquake is associated with early puberty, in both boys and girls.MethodsWe used data from two circles of a survey on reproductive health in China to explore the impact of the Wenchuan earthquake on early puberty , and a total of 9,785 adolescents (4,830 boys, 49.36%) aged 12–20 years from 29 schools in eight provinces were recruited. Wenchuan earthquake exposure was defined as those Sichuan students who had not experienced oigarche/menarche before May 12, 2008. Early puberty was identified as a reported onset of oigarche/menarche at 11 years or earlier. We tested the association between the Wenchuan earthquake and early puberty in boys and girls. Then, subgroup analysis stratified by the age at earthquake exposure also was performed.ResultsIn total, 8,883 adolescents (4,543 boys, 51.14%) with a mean (SD) age of 15.13 (1.81) were included in the final sample. In general, children exposed to the earthquake had three times greater risk of early puberty (boys, RR [95% CI] = 3.18 [2.21–4.57]; girls: RR [95%CI] =3.16 [2.65–3.78]). Subgroup analysis showed that the adjusted RR was 1.90 [1.19–3.03] for boys and 2.22 [1.75–2.80] for girls. Earthquake exposure predicted almost a fourfold (RR [95%CI] = 3.91 [1.31–11.72]) increased risk of early puberty in preschool girls, whereas the increase was about twofold (RR [95%CI] = 2.09 [1.65–2.64]) in schoolgirls. Among boys, only older age at earthquake exposure was linked to early puberty (RR [95%CI] = 1.93 [1.18–3.16]).ConclusionsWenchuan earthquake exposure increased the risk of early puberty in boys and girls, and preschoolers were more at risk than schoolchildren. The implications are relevant to support policies for those survivors, especially children, to better rebuild after disasters.

Developmental Adaptation to Stress: An Evolutionary Perspective

“…Similar effects may occur in response to natural disasters. In a large Chinese study, exposure to the Wenchuan earthquake predicted a fourfold increase among preschool-age girls (under age 7 at the time of exposure) and a twofold increase among school-age girls (age 7 or older at the time of exposure) in rates of early menarche (Lian et al 2018), suggesting an early sensitive period for stress-mediated acceleration of pubertal development. Although earlier puberty is associated with childhood exposure to a variety of psychosocial stressors, the most consistent psychosocial predictor of early puberty in females is a history of sexual abuse (e.g., Magnus et al 2018, Mendle et al 2016.…”

“…Although more research is clearly needed, and the transition toward less positive HPA-HPG coupling may begin quite early in pre-adolescent girls growing up under stressful conditions (Black et al 2018), early HPA-HPG coupling could serve as a mechanism through which childhood stress promotes earlier pubertal development ( Joos et al 2018, Ruttle et al 2015. The Wenchuan earthquake study (Lian et al 2018) suggests that the first 5-7 years of life are a sensitive period for the effects of early life stress on pubertal maturation [as originally proposed by Belsky et al (1991)]. In the context of early life stress (presumably during this sensitive period) and the resulting upregulation of basal cortisol, accelerated positive HPA-HPG coupling in early adolescence may operate as a permissive signal that hastens the onset of puberty.…”

Maternal exposure to Wenchuan earthquake and prolonged risk of offspring birth outcomes: a natural experiment study

“…Although the CLDS was a cross-sectional observational study, the Wenchuan earthquake generated a natural experimental setting to investigate the long-term effects of the earthquake for birth outcomes among the female survivors who became pregnancy years following the devastating earthquake [ 13 , 16 ]. In this natural experiment, the earthquake event that divided the participants into exposed and unexposed groups was unexpected and not under the control [ 17 ].…”

“…The disaster was one of the biggest and deadliest earthquakes in Chinese history, it affected more than 15 million people and left 4.8 million people homeless [ 12 ]. Existing studies assessed the long-term effects of the earthquake on mental health [ 12 ] and puberty timing [ 13 ] among the adolescent survivors. No studies to date, however, have evaluated the long-term effects of 2008 Wenchuan earthquake on birth outcomes, although a hospital-based study showed increased ratios of LBW and PTB within the first 12 months post-disaster in 2 counties affected by Wenchuan earthquake [ 8 ].…”

Cross-cultural evidence does not support universal acceleration of puberty in father-absent households

“…Empirical work on the psychosocial acceleration hypothesis has confirmed that it is a stressful family environment, rather than simple father absence or presence, that seems to have most power to explain early maturation [17 -19]. Psychosocial stress from causes other than family relationships has also been shown to be associated with early puberty in high-income populations [20]; childhood sexual abuse, for example, has shown very consistent associations with earlier puberty [21]. Girls in WEIRD populations from socioeconomically disadvantaged families also experience earlier puberty than those from more advantaged backgrounds, which has been interpreted as further evidence that harsh early environments, with relatively high mortality rates, adaptively accelerate life-history strategy [22,23].…”