Influence of immigration on the weight of newborns in Spain

. FUSTER, V., BLANCO VILLEGAS, M.J., COLANTONIO, S.E., ZULUAGA, P., ROMÁN-BUSTO, J.

Praga, República Checa

Congreso; Vth International Anthropological Congress of Ales Hrdlicka.; 2009

Czech Anthropological Society

Objective: To analyze temporal changes of mean birth weight data regarding variation in age atmaternity and the influence of immigrant women at present residing in Spain.Methods: Information on individual births occurring between 1980 and 2006 (the last yearavailable) was obtained from the Spanish National Institute for Statistics (INE). In the presentanalysis only children born alive corresponding to single maternities were considered to avoid bias regarding multi-parity. In order to be included in this study, mothers had to be residents of Spain.Since 1996 nationality of the mothers (Spanish or immigrant) was taken into account. Male andfemale newborns were analyzed separately regarding parity and maternal age.Results: From 1980 to 2006 the decrease in the average weight of newborns was 155 grams formales and 147 for females. During this time span maternal age progressively increased from 27.1 to30.8. Weight of newborns classified according to the mother’s nationality, has stabilized since2001, regardless of sex, among Spanish women, while foreign mothers gave birth to heavieroffspring. This difference is due to a larger proportion of newborns surpassing 4000g and fewer low weight maternities (1500-2500g) in comparison to Spanish women. Considering weight average, slightly lower values are associated with the first parity. This circumstance is more frequently observed among Spaniards. Maturation of the child, expressed as the duration of the pregnancy, does not appear clearly related to these weight changes.Conclusions: Differences in age at maternity as well as in medical attention received duringpregnancy between both groups of mothers may have had influence on the variation in weight. With the contribution of foreign women to fecundity in Spain, the reduction of the mean weight ofnewborns has been less evident.