Seasonality of birth in India
- PMID: 721846
- DOI: 10.1017/s0021932000011901
Seasonality of birth in India
Abstract
PIP: The article compares seasonal variation in conception in Baroda and Manipal, both at sea level on the west coast of India. The maximum seasonal difference in mean monthly temperature is 3.5 degrees C in Manipal, and 11.3 degrees C in Baroda. Both are industrialized towns, Manipal serving the surrounding taluk of Udupi. Clinical records were obtained from local hospitals; it must be remembered that birth registration in India is compulsory. The number of births in each month were aggregated for the period under review and adjusted to standard month of 30 days, from which an annual mean was calculated. A similar procedure was used to find mean annual temperature. A few relationships are apparent: 1) conception correlates inversely with temperature at both places, 2) abortions and stillbirths are higher in the hottest weather at both places, 3) in Baroda, but not in Udupi, the maximum prematurity rate occurs 5 months after the hottest weather. The links between weather and variations in human reproduction are not clear. Although patterns are not consistent, the conception rate appears to be low at times of maximum temperature. A number of biological and social factors, such as a rise in testicular temperature, can lead to oligospermia. Maternal body temperature can affect the life of spermatozoa, and climate influences the frequency of coitus. Implications from these variations must be taken into consideration in designing new family planning services.