Limitations
Anxiety
A placebo control was not included in the interventional study because of humanitarian considerations. The State–Trait Anxiety Inventory and the Manifest Anxiety Scale were not used in addition to EPDS. Socio-economic status was not assessed. The omega-3 fatty acid contents in the consumed oils were not precisely adjusted. Analysis of blood fatty acids alone did not depict a complete picture of the changes in the brain. The results obtained here may be limited to pregnant women in such regions since Japan is a region where the intake of omega-3 fatty acids is generally higher than in other countries.