LAUSR

A number of studies have reported that pre-pregnancy overweight status is associated with offspring obesity, yet only a few studies have examined pre-pregnancy underweight status as it associates with offspring health. The aim of the present study was to assess the effect of pre-pregnancy underweight status in a mother on health outcomes in her offspring. To this end, the primary outcome examined in the present study was underweight status in the offspring, with a secondary outcome of offspring low bone mass. The present retrospective cohort study, conducted from 2008 to 2011, targeted a source population of all students registered as fifth-graders at three public elementary schools in Hamamatsu and Fukuroi cities. Maternal height and weight before and after pregnancy and offspring weight and height at birth were obtained from the Maternal and Child Health Handbook. Offspring weight and height at age 10 years were measured using standard procedures. Offspring total body less head (TBLH) bone mineral content (BMC) was determined with a dual-energy X-ray absorptiometry scanner. Pre-pregnancy underweight status was found to be associated with an increased risk of an underweight status in female offspring (OR = 2.88, 95% CI 1.06–7.81). Offspring TBLH BMC in the underweight mother group was significantly lower than that in the non-underweight mother group. We determined that pre-pregnancy underweight status was more likely to lead to an underweight status and low TBLH BMC in school-aged offspring.