Low-dose aspirin to prevent preeclampsia and growth restriction in nulliparous women identified by uterine artery Doppler as at high risk of preeclampsia: A double blinded randomized placebo-controlled trial

The effects of low-dose aspirin on preterm birth: a systematic review and meta-analysis of randomized controlled trials

AIM

To conduct a systematic review and meta-analysis of all randomized controlled trials (RCTs) that evaluated the efficacy of low-dose aspirin (LDA, ≤ 160 mg/day) on preventing preterm birth (PB).

METHODS

Five databases were screened from inception until June 25, 2023. The RCTs were assessed for quality according to Cochrane's risk of bias tool. The endpoints were summarized as risk ratio (RR) with 95% confidence interval (CI).

RESULTS

Overall, 40 RCTs were analyzed. LDA significantly decreased the risk of PB < 37 weeks (RR: 0.91, 95% CI 0.87, 0.96, p < 0.001, moderate certainty of evidence) with low between-study heterogeneity (I2 = 23.2%, p = 0.11), and PB < 34 weeks (RR: 0.78, 95% CI 0.61, 0.99, p = 0.04, low certainty of evidence) with high between-study heterogeneity (I2 = 58.3%, p = 0.01). There were no significant differences between both groups regarding the risk of spontaneous (RR: 0.94, 95% CI 0.83, 1.07, p = 0.37) and medically indicated (RR: 1.28, 95% CI 0.87, 1.88, p = 0.21) BP < 37 weeks. Sensitivity analysis revealed robustness for all outcomes, except for the risk of PB < 34 weeks. For PB < 37 weeks and PB < 34 weeks, publication bias was detected based on visual inspection of funnel plots for asymmetry and statistical significance for Egger's test (p = 0.009 and p = 0.0012, respectively).

CONCLUSION

LDA can significantly reduce the risk of PB < 37 and < 34 weeks. Nevertheless, further high-quality RCTs conducted in diverse populations, while accounting for potential confounding factors, are imperative to elucidate the optimal aspirin dosage, timing of initiation, and treatment duration for preventing preterm birth and to arrive at definitive conclusions.

The optimal dosage of aspirin for preventing preeclampsia in high-risk pregnant women: A network meta-analysis of 23 randomized controlled trials

This study aimed to assess the effectiveness and optimal dosage of aspirin in preventing preeclampsia in high-risk pregnant women. Traditional and network meta-analyses were conducted on data from 23 randomized controlled trials involving 10 547 pregnant women. The findings demonstrated that aspirin significantly reduced the incidence of preeclampsia (OR = 0.66, 95%CI [0.58, 0.75]), with the best preventive effect observed at a dosage of 80-100 mg/day (OR = 0.51, 95%CI [0.36, 0.72]). No significant differences were found in the occurrence of postpartum hemorrhage (OR = 1.03, 95%CI [0.79, 1.33]), small for gestational age (OR = 0.83, 95%CI [0.50, 1.35]), placental abruption (OR = 0.96, 95%CI [0.53, 1.73]), and intrauterine growth restriction (OR = 0.63, 95%CI [0.45, 1.86]) between women taking aspirin and those taking placebos. Different doses of aspirin showed a reduction in preeclampsia incidence, but there was no significant difference in efficacy between the dosage groups. Side effects did not significantly differ between placebo and different aspirin dosage groups. SUCRA analysis suggested that 80-100 mg/day may be the optimal dosage, prioritizing both effectiveness and minimizing side effects. Sensitivity analysis confirmed the robustness of the findings. However, improvements are needed in addressing issues like loss to follow-up, reporting bias, and publication bias. In conclusion, a dosage of 80-100 mg/day is recommended for preventing preeclampsia in high-risk pregnant women, although individual circumstances should be considered for optimizing the balance between effectiveness and safety.

Assessing the Impact of Uterine Artery Doppler and Low-Dose Aspirin on Fetomaternal Outcome: A Prospective Study in Low-Risk Pregnant Women in Western Part of India

Introduction Fetal growth restriction (FGR) and pregnancy-induced hypertension (PIH) are significant and clinically relevant complications observed in many pregnancies. Early prediction of these complications may be possible through the assessment of the umbilical artery pulsatility index (UAPI). However, its utility in routine practice for otherwise normal pregnancy needs further exploration in India. Objectives This study aimed to evaluate the potential benefits of incorporating UAPI for the timely use of low-dose aspirin in preventing FGR and PIH in a tertiary care hospital in the western part of India. Methodology A prospective study was conducted involving 64 low-risk (i.e., not having any feature of high-risk pregnancy) pregnant women selected from routine antenatal care outpatient departments over a period of two years. All women underwent uterine artery Doppler examination during the 11-13+6 weeks of pregnancy and those who had high UAPI received low-dose (150 mg) aspirin till the 35th week. The incidence of FGR and PIH was analyzed and compared between high UAPI and normal UAPI pregnancy. Results A total of 64 pregnant women with a mean age of 27.11±4 years participated in the study. Among the women, eight (12.5%) were found to have high UAPI and were put on aspirin. Among those eight women, two developed PIH. In the normal UAPI group, nine (16.07%) developed PIH (p-value = 0.62). FGR was found in one case among the eight who received aspirin and in eight cases among the 56 who had normal UAPI (p-value > 0.99). Conclusion The study concluded that despite having normal UAPI, women categorized as low-risk may develop PIH and FGR. Hence, the routine use of UAPI should be investigated in further cohort studies using a large sample to draw a generalizable conclusion for the Indian population.