Short‐term fetal nutritional stress and long‐term health: Child height

Abstract

Objective: This study examined the impact of in utero exposure to Ramadan, the Islamic fasting month, by trimester on height at ages 0 to 18 for a sample of children from Tehran, Iran. If exposure to Ramadan is associated with significant nutritional stress to the fetus, the fetus's adaptive responses to nutritional insufficiency could manifest as changes in height during childhood, long before any effects on aging or disease risk at older ages.Methods: Children who were exposed and not exposed to Ramadan in utero were compared to identify any systematic difference between their parents' and households' characteristics (including height, age, education, and indicators of wealth). Also, the seasonal pattern of food consumption in Tehran was analyzed. Finally, the association of child height with prenatal exposure to Ramadan was measured, controlling for seasonality and parent and household.Results: Ramadan associated fasting in the second trimester of gestation was associated with 0.091 age-adjusted SDs (ie, 0.60-0.67 cm) decrease in children's height at age 10 years or older. The negative association was largest in male children and was approximately 1 cm at age 12 years or older among male children. Conclusion:Maternal Ramadan fasting in the second trimester, the critical period for long bone development, was associated with decreased height. Exposure to ritual fasting is important because approximately 75% of all Muslim children are exposed to Ramadan in utero.

Long-Term Outcomes of in Utero Ramadan Exposure: A Systematic Literature Review

“…Six studies were conducted in South East Asia (all in Indonesia) [21][22][23][24][25][26], one in South Asia (Pakistan) [27], two in Eastern Mediterranean region (Iran) [28,29], two in Africa (one in Burkina Faso [12] and one in Ethiopia [30]) and three in Europe (one in England [31] and two in Denmark [32,33]). Two studies had a cross-regional focus including 39 countries in Eastern Europe, Africa, Eastern Mediterranean, Asia, and North America [34,35].…”

“…All studies used retrospective longitudinal data for analysis. Six manuscripts used nationally representative data from the Indonesian Family Life Survey (IFLS) [21][22][23][24][25]; one used data from the district-based Punjab Multiple Indicator Survey (MICS) [27]; two used school register data [28,31]; one used data from the Urban Health Equity and Assessment Response Tool (Urban HEART) [29]; two used Danish administrative records [32,33]; one study used Michigan (United States) natality data and census data for Iraq and Uganda [34]; one used data from the Nouna Health and Demographic Surveillance System in northwestern Burkina Faso [12]; one used data from the Ethiopia Demographic and Health Survey [30]; and one analyzed data collected from 98 demographic and health surveys [35].…”

“…Studies investigated the children of Muslim parents [21,23,30,[32][33][34], children of Ramadan-exposed Muslim mothers (experiencing Ramadan during pregnancy, with unknown fasting status) [21,22,[24][25][26][27]29,31,35], and children of Ramadan fasting mothers [28]. All studies included non-exposed control groups represented by children of non-Muslim parents [21,23,30,[32][33][34], children of non-exposed mothers (no Ramadan during pregnancy) [21,22,[24][25][26][27]29,31,35], and children of non-fasting Muslim mothers [28]. Most studies targeted more than one age group, although some others targeted only children [27,29,31], adolescents [32], and adults [22,34].…”

“…All studies included non-exposed control groups represented by children of non-Muslim parents [21,23,30,[32][33][34], children of non-exposed mothers (no Ramadan during pregnancy) [21,22,[24][25][26][27]29,31,35], and children of non-fasting Muslim mothers [28]. Most studies targeted more than one age group, although some others targeted only children [27,29,31], adolescents [32], and adults [22,34].…”

“…Most studies [12,[21][22][23][24][25][26][27][29][30][31][33][34][35] used an intention-to-treat design by estimating the Ramadan exposure based on an individual's date of birth, calculating if Ramadan overlapped with the pregnancy, assuming a full-term birth (individual's mother's fasting status unknown). One study used questionnaire data asking mothers about fasting throughout their pregnancies, defining in utero Ramadan exposure as fasting for at least 27 days during pregnancy [28].…”