The effect of maternal age and duration of labor on perinatal and neonatal outcomes: a retrospective cohort study.

BACKGROUND

This study aimed to investigate the effect of maternal age and duration of labor on perinatal and neonatal outcomes. The results of this study are expected to provide a basis to aid maternal and child health care personnel to implement health education for late childbearing women.

METHODS

This was a retrospective observational study, wherein 9,241 parturients were included from 2016 to 2018. Parturients were divided into three groups based on age: <28 (n=2,911), 28-30 (n=3,631), and >30 (n=2,699) years. According to the total duration of labor, those who did not undergo cesarean section (CS) were subgrouped into <420 minutes (n=4,065) and ≥420 minutes (n=4,094) groups. A multivariate logistic regression model was used to investigate associations between age/total duration of labor group factors to different postpartum outcomes, including a switch to emergency CS, puerperal morbidity, abnormal fetal heart rate, and meconium-stained amniotic fluid (MSAF).

RESULTS

The rates of postpartum outcomes significantly differed in maternal age groups, including switch to emergency CS (9.07% 13.03% 11.23%; P<0.001), puerperal morbidity (6.32% 6.46% 5.00%; P=0.035), and abnormal fetal heart rate (25.34% 28.21% 25.67%; P=0.017). Of the comparisons between labor time groups, it was found that participants with longer labor time were also significantly higher in the use of episiotomy/forceps (46.61% 69.77%; P<0.001), bleeding amount (381.35±108.02 389.60±146.40 mL; P=0.004), oxytocin use (25.03% 39.56%; P<0.001), puerperal morbidity (1.98% 6.86%; P<0.001), abnormal fetal heart rate (20.07% 25.15%; P<0.001), and MSAF (26.53% 31.91%; P<0.001). Multivariate logistic regression analysis showed that as age increased, the ORs of switching to emergency CS (1.58 and 1.87, both P<0.001) and having abnormal fetal heart rate (1.20 and 1.38; both P<0.01) also increased. Participants with longer labor time groups the ORs of puerperal morbidity (2.33; P<0.001) and MSAF (1.13; P=0.023) also increased.

CONCLUSIONS

With the adjustment of covariates. Higher maternal age seems associated to the risk of switching to emergency CS and having abnormal fetal heart rate; longer total duration of labor seems associated to the risk of puerperal morbidity and MSAF.