Related Experiment Video
Updated: Apr 5, 2026
Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts
Published on: January 29, 2018
[Secular variation of births, weight and length at birth: Local perspective]
Hugo Amigo1, Patricia Bustos2, Claudio Vargas2
1Doctor en Salud Pública, Departamento de Nutrición, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
Insights
Birth rates declined significantly at Limache Hospital between 1974 and 2011, while infant anthropometric measurements, including birth weight and length, showed significant improvements. These trends in birth outcomes are crucial for public health interventions.
Area of Science:
- Public Health
- Pediatrics
- Epidemiology
Background:
- Analysis of birth outcomes and anthropometric measurements is essential for understanding population health trends.
- Longitudinal data from a single institution can provide valuable insights into demographic and health shifts.
Purpose of the Study:
- To analyze trends in live births and anthropometric measurements (birth weight and length) at Limache Hospital from 1974 to 2011.
- To identify changes in the incidence of low birth weight and low birth length over the study period.
Main Methods:
- Time series analysis of 17,574 births.
- Modeling trends using linear and logistic regressions with splines to detect changes by decade.
- Statistical analysis to assess significance of observed trends.
Main Results:
- A significant decline in annual births was observed from the 1970s through the 1990s.
- Mean birth weight increased by 266 grams, and mean birth length increased by 1 cm between the 1970s and 2000-2011.
- Incidence of low birth weight decreased from 8% to 1.1%, and low birth length decreased from 7.6% to 2.1%.
Conclusions:
- Live births decreased, while anthropometric measurements at birth improved significantly at Limache Hospital during the study period.
- Findings highlight the need for targeted public health interventions.
- Potential selection biases should be considered when interpreting these birth outcome estimates.
Objective:
To analyse the outcomes of births and anthropometric measurements at birth of children born between 1974 and 2011 at Limache Hospital (Valparaíso, Chile).
Patients And Method:
Times series were constructed of births, weight and length at birth, and low weight and length at birth. The trend was modelled with linear and logistical regressions using splines to represent breaks in the trend by decade.
Results:
The series includes 17,574 births. There was an increase in births per year in the 1970s (30/year) and declines in them to 17 and 22 births/year in the 1980s and 1990s, respectively (P<.001), with no significant trend thereafter. Newborns from 2000 to 2011 weighed 266 grams more than those in the 1970s (P<.001), and have now reached a mean weight of 3,530 g. Low birthweight fell from 8% in the 1970s to 1.1% after 2000. Birth length increased by 1cm in the 37 years studied, with a reduction of low birth length from 7.6% to 2.1% during the period.
Conclusion:
Live births in the Limache Hospital declined, and anthropometric measurements at birth improved in the years analysed. This information is useful in developing interventions, taking into account the possible selection biases that could distort these estimates and their interpretation.
Related Concept Videos
01:52Regression Toward the Mean
02:32Variation: Normal Distribution, Range, and Standard Deviation
01:22Applications of Life Tables
00:57Population Growth
01:20Variation in Acceleration due to Gravity near the Earth's Surface
The difference between the true and apparent weights is proportional to the square of the Earth's...
01:11Normal Distribution