It is undetermined which blood variables related to iron storage during the first trimester of pregnancy could efficiently predict anemia occurring during the third trimester. Red blood cell count (RBC), hemoglobin concentration, hematocrit, ferritin, iron, and total iron binding capacity (TIBC) were assessed longitudinally during the first, second, and third trimesters of 231 healthy Japanese women. None of the patients had anemia in the first trimester and none used iron supplementation before the second trimester blood test. Anemia was defined as hemoglobin (Hb) < 11 g/dL for the first trimester and Hb < 10.0 g/dL for the third trimester. Forty-seven (20%) women developed anemia in the third trimester. The first trimester RBC, Hb, hematocrit, and ferritin levels were significantly lower in women with third-trimester anemia than those without anemia. The first trimester hemoglobin level exhibited a greater area under the curve of the receiver operating characteristic curve for prediction of the third trimester anemia than other blood variables; the optimal cut-off (12.6 g/dL) of hemoglobin yielded a sensitivity of 83% (39/47). First trimester hemoglobin levels were significantly better predictors of anemia during the third trimester than the indices of iron storage, including serum iron, ferritin, and TIBC levels.

Suicide due to postpartum depression is the most common perinatal-related death and is a social concern in Japan. Nutritional deficiencies during pregnancy may contribute to postpartum depression; therefore, we investigated the relationship between postpartum depression and nutritional status during pregnancy and postpartum. We focused specifically on ketone bodies because they are known to protect brain cells. The relationship between the Edinburgh Postnatal Depression Scale (EPDS) scores and the serum levels of ketone bodies and vitamin D, thyroid function, and iron metabolism was examined. Overall, 126 pregnant women were identified for the study, and 99 were eventually included in the analysis. We defined an EPDS score of ≥9 as being positive for postpartum depression, and serum ketone levels were found to be higher in the group with an EPDS score of ≥9 during the second trimester; however, there were no other significant findings. We may be able to predict postpartum depression from a pregnant woman’s serum ketone levels in the second trimester. There was a positive correlation between the EPDS scores at 3 days and 1 month postpartum (r = 0.534, p < 0.001). EPDS scores assessed in the early postpartum period may be useful for the timely detection of postpartum depression.

Among the physiological changes occurring during pregnancy, the benefits of morning sickness, which is likely mediated by human chorionic gonadotropin (HCG) and induces serum ketone production, are unclear. We investigated the relationship between serum levels of ketone bodies and HCG in the first, second, and third trimesters and neonatal body shape (i.e., birth weight, length, head circumference, and chest circumference) in 245 pregnant women. Serum levels of 3-hydroxybutyric acid peaked in late-stage compared with early stage pregnancy (27.8 [5.0–821] vs. 42.2 [5.0–1420] μmol/L, median [range], p < 0.001). However, serum levels of ketone bodies and HCG did not correlate with neonatal body shape. When weight loss during pregnancy was used as an index of morning sickness, a higher pre-pregnancy body mass index was associated with greater weight loss. This study is the first to show that serum ketone body levels are maximal in the third trimester of pregnancy. As the elevation of serum ketone bodies in the third trimester is a physiological change, high serum levels of ketone bodies may be beneficial for mothers and children. One of the possible biological benefits of morning sickness is the prevention of diseases that have an increased incidence due to weight gain during pregnancy.