Maternal depressive symptoms, sleep, and odds of spontaneous early birth: implications for racial inequities in birth outcomes

Abstract

Study objectives: Delivery prior to full term affects 37% of US births, including ~400,000 preterm births (<37 weeks) and >1,000,000 early term births (37-38 weeks). Approximately 70% of cases of shortened gestation are spontaneous-without medically-indicated cause. Elucidation of modifiable behavioral factors would have considerable clinical impact.

Methods: This study examined the role of depressive symptoms and sleep quality in predicting the odds of spontaneous shortened gestation among 317 women (135 black, 182 white) who completed psychosocial assessment in mid-pregnancy.

Results: Adjusting for key covariates, black women had 1.89 times higher odds of spontaneous shortened gestation compared to White women (OR [95% CI] = 1.89 [1.01, 3.53], p = 0.046). Women who reported only poor subjective sleep quality (PSQI > 6) or only elevated depressive symptoms (CES-D ≥ 16) exhibited no statistically significant differences in odds of spontaneous shortened gestation compared to those with neither risk factor. However, women with comorbid poor sleep and depressive symptoms exhibited markedly higher odds of spontaneous shortened gestation than those with neither risk factor (39.2% versus 15.7% [OR (95% CI) = 2.69 (1.27, 5.70)], p = 0.01). A higher proportion of black women met criteria for both risk factors (23% of black women versus 11% of white women; p = 0.004), with a lower proportion experiencing neither risk factor (40.7% of black versus 64.3% of white women; p < 0.001).

Conclusions: Additive effects of poor subjective sleep quality and depressive symptoms were observed with markedly higher odds of spontaneous shortened gestation among women with both risk factors. Racial inequities in rates of comorbid exposure corresponded with inequities in shortened gestation. Future empirical studies and intervention efforts should consider the interactive effects of these commonly co-morbid exposures.

Keywords: depression; depressive symptoms; early term birth; mental health; pregnancy; preterm birth; racial inequities; shortened gestation; sleep.

Figure 1.

Sleep and rates of shortened gestation by race. In a model with PSQI and race and adjusting for age, income, and BMI, compared to women with PSQI ≤ 6, those with PSQI > 6 did not differ significantly in risk for spontaneous shortened gestation (OR [95% CI] = 1.44 [0.80, 2.57], p = 0.22). In this model, Black women were marginally more likely to have higher risk of spontaneous shortened gestation (p = 0.057) (bars indicate 95% confidence intervals).

Figure 2.

Depressive symptoms and rates of shortened gestation by race. In a model with CES-D and race and adjusting for age, income, and BMI, compared to women with CES-D <16, those with CES-D ≥ 16 had significantly greater risk for shortened gestation (OR [95% CI] = 2.28 [1.20, 4.33]; p = 0.01). In this model, Black women had 1.76 times higher odds of spontaneous shortened gestation (95% CI = 0.93, 3.33; p = 0.08) (bars indicate 95% confidence intervals).

Figure 3.

Sleep, depressive symptoms, and rates of shortened gestation by race. Race and risk factor categorization were included in the same model along with covariate controls. Compared to women with neither risk factor, women with both poor sleep and significant depressive symptoms had higher odds of spontaneous shortened gestation (OR [95% CI] = 2.69 [1.27, 5.70], p = 0.01). After accounting for these covariates, black race was not statistically significantly associated with spontaneous shortened gestation in this model (OR [95% CI] = 1.80 [0.95–3.41], p = 0.07) (bars indicate 95% confidence intervals).