Stillbirth pattern in an isolated Mediterranean population: La Alpujarra, Spain

This study attempted to analyze the effect of several factors on the stillb irth pattern in a relatively isolated rural population, La Alpujarra (Spain ), during the first half of the 20th century. The study was a retrospective analysis from a total sample of 2199 births to 525 mothers, allowing for b irth year of mother, maternal age, parental inbreeding, family size, birth order, sex, single/twin delivery, and birth interval. Binomial probability distribution of stillbirths provided no evidence for any significantly incr eased risk in relation to family size. Analysis of covariance (ANCOVA) of s tillbirth risk in affected families indicated a significant effect for sex of the child, parental consanguinity, and birth year of mother. Logistic re gression showed increased risk in twin delivery and pregnancy order one, bu t not for birth order other than one. Multivariate analysis of variance (MA NOVA) testing for differences between affected and unaffected families supp orted a temporal decrease of stillbirths during the period studied. Althoug h the birth interval average was significantly shorter in affected families (p < 0.0001), this association did not hold, in a more detailed analysis, for individual intervals in these families (p = 0.20). There was no signifi cant effect of maternal age on stillbirths in the whole sample or limited t o first pregnancies. These results suggest that birth order one and twin de livery were the main determinants of the stillbirth pattern in La Alpujarra . Furthermore, our data indicate that the decline in stillbirth rate began before medical facilities for perinatal care became available, which was no t until after 1950. The temporal decrease in stillbirth rates may therefore be related to an increasing social attention to deliveries rather than to prenatal care medical facilities.