Intergenerational birth weights among the direct female descendants of US-born and Mexican-born Mexican-American women in Illinois: an exploratory study.

OBJECTIVE: To explore the intergenerational birth-weight patterns of the direct female descendants of Mexican-American women. DESIGN: This is a population-based study. METHODS: Stratified analyses were performed on a transgenerational dataset of 1956-1975 and 1989-1991 Illinois computerized vital records of Mexican-American infants. RESULTS: Among the descendants of generation 1 US-born Mexican-American women (n=1,940), generation 3 females had a birth weight equivalent to that of their generation 2 mothers, (3294 g vs 3283 g); generation 3 infants with unmarried mothers had a birth weight 121 g less than that of generation 2 infants born to unmarried mothers (3163 g vs 3284 g, P<.01); and generation 3 female infants born to teenaged women had a birth weight 70 g less than that of their generation 2 mothers who were born to teenaged women (3178 g vs 3248 g, P<.01). Among the descendants of generation 1 Mexican-born women (n=1,017), generation 3 females had a birth weight equivalent to that of their generation 2 mothers (3335 g vs 3363 g); generation 3 infants with teenaged mothers had a birth weight 108 g less than that of generation 2 infants with teenaged mothers (3264 g vs 3372 g, P<.01). CONCLUSIONS: An intergenerational rise in birth weight does not occur among the direct female descendants of Mexican-American women.