ABSTRACT
BACKGROUND: After the implementation of the universal two-child policy in China, it was more frequent to have long interpregnancy intervals (IPIs) and advanced maternal age. However, the interactions between long IPIs and advanced maternal age on neonatal outcomes are unknown. METHODS: The study subjects of this historical cohort study were multiparas with singleton live births between October 1st, 2015, and October 31st, 2020. IPI was defined as the interval between delivery and conception of the subsequent pregnancy. Logistic regression models were used to calculate adjusted odds ratios (aORs) and 95% confidence intervals (CIs) of the risks of preterm birth (PTB), low birth weight (LBW), small for gestation age, and 1-min Apgar score ≤ 7 in different IPI groups. Relative excess risk due to interaction (RERI) was used to evaluate the additive interaction between long IPIs and advanced maternal age. RESULTS: Compared with the 24 ≤ IPI ≤ 59 months group, the long IPI group (IPI ≥ 60 months) was associated with a higher risk of PTB (aOR, 1.27; 95% CI: 1.07-1.50), LBW (aOR, 1.32; 95% CI 1.08-1.61), and one-minute Apgar score ≤ 7 (aOR, 1.46; 95% CI 1.07-1.98). Negative additive interactions (all RERIs < 0) existed between long IPIs and advanced maternal age for these neonatal outcomes. Meanwhile, IPI < 12 months was also associated with PTB (aOR, 1.51; 95% CI 1.13-2.01), LBW (aOR, 1.50; 95% CI 1.09-2.07), and 1-min Apgar score ≤ 7 (aOR, 1.93; 95% CI 1.23-3.04). CONCLUSIONS: Both short and long IPIs are associated with an increased risk of adverse neonatal outcomes. Appropriate IPI should be recommended to women planning to become pregnant again. In addition, better antenatal care might be taken to balance the inferiority of advanced maternal age and to improve neonatal outcomes.
ABSTRACT
A split plot experiment was conducted in greenhouse to investigate the effects of irrigation lower limit and maize straw returning on the yield, quality, and water use efficiency (WUE) of tomato. Maize straw was applied for 1 (2018, A1), 2(2017, A2), and 3 (2016, A3) years at different amounts (0, 1.5×104, 3×104, 4.5×104 kg·hm-2) and different irrigation lower limits (50%θf, 60%θf, 70%θf, 80%θf, θf was the field water capacity). Variance analysis, entropy-weight and TOPSIS methods were used to examine the responses of yield, quality and water use efficiency (WUE) of tomato. The results showed that tomato yield was enhanced by the increases of irrigation lower limit. The maximum value of yield was observed in the 80%θf treatments, with the maximum average yield of 93.55 t·hm-2 in A1, 87.23 t·hm-2 in A2, and 99.34 t·hm-2 in A3, respectively. WUE and quality of tomato decreased with increasing irrigation lower limit. In the first year of straw returning, the maximum average yield of tomato was 99.60 t·hm-2 in straw returning 1.5×104 kg·hm-2 . In the second and third years, 4.5×104 kg·hm-2 straw returning had the highest average yield of tomato, which was 92.50 and 107.75 t·hm-2, respectively. The maximum WUE was observed with the straw returning of 1.5×104 kg·hm-2 in A1 and A2, while in the A3 treatment it happened in straw returning of 4.5×104 kg·hm-2. The quality index of tomato showed different trends with the increases of straw returning years and amount.
