Changes of maternal dietary intake, bodyweight and fetal growth throughout pregnancy in pregnant Japanese women

Aim The associations among changes in dietary intake, maternal bodyweight, and fetal growth during the course of pregnancy were investigated in a prospective cohort study carried out on 135 Japanese women. Material and Methods Dietary intake was analyzed using digital photos of meals taken over 3 consecutive days, in the first, second and third trimester, and was compared with maternal bodyweight, estimated fetal bodyweight by ultrasound examination, and birthweight. Results Surprisingly, the mean total calorie intake remained below 1600 kcal/day during pregnancy, much lower than the value recommended in the 2010 edition of 'Dietary Reference Intakes for Japanese'. Dietary intake was similar throughout despite the recommendation of extra intake in late pregnancy. Maternal dietary intake did not correlate with fetal growth, although maternal bodyweight in the second trimester positively correlated with estimated fetal bodyweight in the third trimester. Maternal bodyweight before pregnancy positively correlated with birthweight. Conclusions Maternal bodyweight as well as eating habits established before pregnancy may have a considerable effect on fetal growth. There is an urgent need to improve the diet of Japanese women of child-bearing age, especially during pregnancy.