Birth intervals and infant mortality in La Cabrera (Spain)

Area of Science:

• Historical Demography
• Reproductive Health
• Family Studies

Background:

• Family reconstitution offers insights into historical reproductive patterns.
• Understanding past reproductive performance is crucial for public health and social science.
• La Cabrera, Spain, provides a unique dataset for this historical demographic analysis.

Purpose of the Study:

• To analyze reproductive performance and infant mortality in La Cabrera, Spain, between 1880 and 1929.
• To identify factors influencing neonatal and postneonatal mortality.
• To determine optimal birth intervals for effective reproduction in this historical context.

Main Methods:

• Utilized family reconstitution for 2293 families (7872 births).
• Analyzed data from 1880 to 1929, focusing on parities 2 to 10.
• Employed logistic regression to assess neonatal and postneonatal mortality risks based on birth intervals and sibling survival.

Main Results:

• 45% of couples achieved effective reproduction with birth intervals of 24–36 months.
• Risk factors for neonatal mortality included birth intervals <17 months, preceding sibling death, and male sex.
• Maternal age and accumulated previous sibling deaths were not significant risk factors.

Conclusions:

• Birth intervals of 24–36 months are associated with the most effective reproduction in historical La Cabrera.
• Specific factors like short birth intervals and sibling mortality significantly increased neonatal mortality risk.
• This study highlights the importance of birth spacing for infant survival in historical populations.