Demographic trends: birth spacing
Vargas, N.A.; Valenzuela, S.; Larrea, B.; MacKenney, J.; Valverde, C.; Valencia, C.
Revista Medica de Chile 117(4): 468-471
1989
ISSN/ISBN: 0034-9887 PMID: 2519406 Document Number: 225039
Results are compared of 2 studies of child spacing undertaken in public maternity hospitals serving middle and lower income populations in the western area of Santiago, Chile. The 1st study surveyed 687 mothers of live-born infants in 1984-85, while the 2nd surveyed 1000 mothers in February-May 1988. All mothers had at least 1 older child. The surveys were undertaken in the 72 hours following delivery. In the 1984-85 and 1988 studies respectively, the birth interval was under 24 months for 19.2 and 21.8%; 24-35 months for 18.9 and 16.0%; 36-47 months for 16.9 and 13.1%; 48-59 months for 11.2 and 9.0%; and 60 months or more for 33.8 and 40.1%. The increase in birth intervals over 60 months was statistically significant. The average birth weight increased from 32.. g to 3330 g between the 2 studies, but the difference was not significant. The average birth weight increased for all birth intervals. The proportion of infants weighing under 2500 g at birth was 5.8% in 1984-85 and 6.9% in 1988. The proportions of mothers who became pregnant despite using a contraceptive method in 1984-85 and 1988 respectively were 28.0 and 30.7% for birth intervals of 24 months or less, 18.3 and 23.1% for intervals of 24-59 months, and 16.8 and 17.5% for intervals of 60 months or more. 22.5% of all infants in the 1988 survey were conceived while their mothers were using a contraceptive method. The factors involved in this apparently high rate, whether related to availability of family planning services, user knowledge, or method efficacy, should be identified and corrected.