Effects of anemia during the third trimester of pregnancy on postpartum depression and pregnancy outcomes in pregnant women older than 35 years: a retrospective cohort study.

BACKGROUND

There is no study on the impact of anemia on postpartum depression and outcomes in mothers older than 35 years, which makes the nursing of these pregnant women with anemia more difficult.

METHODS

We retrospectively collected the demographic and clinical characteristics of pregnant women older than 35 years at conception between August 2014 and December 2019. Hemoglobin less than 110 g/L was defined as anemia. Postpartum depression was assessed according to Edinburgh Postnatal Depression Scale. A subgroup analysis was performed by dividing anemia into mild anemia or moderate and severe anemia. All participants were followed up for at least 3 months postpartum and their pregnancy outcomes were recorded. The existence of postpartum depression was evaluated at 4 weeks postpartum. The risk factors of anemia during the third trimester of pregnancy and the impacts of anemia on postpartum depression and pregnancy outcomes were analyzed using multivariable logistic regression analysis.

RESULTS

A total of 519 pregnant older than 35 years women were included in this study, including 281 without anemia and 238 with anemia. No significant difference was found in the incidence of postpartum depression between anemia and non-anemia groups (18.9% vs. 12.8%, P=0.057), while the anemia group had significantly higher incidence of preterm delivery, prolonged labor, and caesarean section. The subgroup analysis found that significantly pregnant women with older age in the moderate or severe anemia subgroup had postpartum depression than those in the mild anemia subgroup (23.2% vs. 12.5%, P=0.038). A higher rate of preterm delivery, prolonged labor, and caesarean section was recorded in the moderate or severe anemia subgroup (8.3% vs. 20.4%, P=0.012; 30.2% vs. 43.0%, P<0.001; 20.8% vs. 40.1%, P=0.002). Moderate or severe anemia, the presence of depression during the first trimester of pregnancy, unplanned pregnancy, and fewer parity were identified as risk factors of postpartum depression in pregnant women older than 35 years with anemia.

CONCLUSIONS

Anemia has significant impacts on pregnancy outcomes in pregnant women older than 35 years. Furthermore, moderate and severe anemia will significantly increase the incidence of postpartum depression, which should be corrected at an early stage to minimize its negative effects.