Do the Emotions of Middle-Income Mothers Affect Fetal Development More Than Those of High-Income Mothers?—The Association between Maternal Emotion and Fetal Development

This study examines the relationship between the emotions of mothers and fetal development and explores the modifying effect that family income has on this relationship. Socio-demographic information, maternal depression, stress, positive and negative emotions, and maternal-fetal attachment data were collected at 16–20 weeks of pregnancy. Data on fetal body weight and biparietal diameter indicating fetal development were collected at 33–35 weeks to observe the longitudinal effects of mothers’ emotions on fetal development. We divided subjects into two groups: those with more than 150% of the median income were classified as the high-income group and less than 150% as the middle-income group. T-test, correlation analysis, and multiple regression analysis on maternal emotional status and fetal development were performed for each group. A positive correlation was found between maternal-fetal attachment and negative emotion that was associated with the biparietal diameter and fetal body weight only in the middle-income group. Results of the multiple regression analysis were statistically significant, indicating that maternal-fetal attachment was associated with fetal weight. These results show that the management of subjective emotion is associated with healthy development of the fetus and contributes to health equity.