Every newborn has the right to be born healthy both mentally and physically. The achievement of this purpose is vital in maternal-fetal medicine, which aims to ensure that every pregnancy results in a healthy mother and baby. The prevalence of intrauterine growth retardation (IUGR) in a population with healthy, well-nourished mothers is approximately 3-5%. [1]In a population where the mother has hypertension or a history of growth-restricted fetuses, the incidence is elevated at 10-20%.[1] The National Neonatal Perinatal Database of India revealed an incidence of Intrauterine Growth Restriction (IUGR) at 9.65% among live births in hospitals, with a prevalence of 43% among infants with very low birth weight [2]. Approximately 18.7% of neonatal fatalities are attributable to birth asphyxia caused by intrauterine growth restriction (IUGR) or pregnancy-induced hypertension (PIH) [3]. Antepartum fetal surveillance constitutes the foundation of preventative obstetric care aimed at reducing maternal and perinatal death and morbidity. The advent of electronic fetal monitoring rendered the hitherto concealed realm of the fetus accessible to modern technologies. In addition to several other non-invasive assessments, such as the non-stress test (NST), which yield data post-onset of clinical symptoms, umbilical artery Doppler scans furnish critical information about the fetus in utero [1]. Doppler sonography provides a distinctive method for the non-invasive assessment of physiological hemodynamic feto-placental blood flow data. Intrauterine growth retardation is associated with distinct anomalies in Doppler parameters. Umbilical artery (UA) Doppler velocimetry is the most thoroughly assessed test of fetal well-being. Doppler ultrasonography studies of human fetal circulation have demonstrated that in cases of intrauterine growth restriction (IUGR), there is a notable reduction in the middle cerebral artery (MCA) pulsatility index compared to normal fetuses [5]. This study aims to determine the efficacy of umbilical artery and middle cerebral artery Doppler ultrasound, together with non-stress testing, in forecasting adverse perinatal outcomes in high-risk pregnancies, such as intrauterine growth restriction (IUGR) and pregnancy-induced hypertension (PIH), and to assess the utility of these assessments in the clinical management of such cases. Despite the abundance of material in international publications, there is a paucity of Indian studies on this subject, particularly in the central region of India. Our objective is to evaluate the relative efficacy of Doppler ultrasound and non-stress testing (NST) in the management of intrauterine growth restriction (IUGR) and severe pre-eclampsia, thereby minimizing fetal morbidities and admissions to the neonatal intensive care unit (NICU). This undertaking aimed to assess and compare the efficacy of ultrasonic scans with Doppler studies and non-stress tests with biophysical profiles to forecast and prompt early actions. The secondary objectives were to identify abnormalities in the feto-placental unit and fetal circulation in fetuses of hypertensive mothers with clinically diagnosed intrauterine growth restriction, to ascertain the presence of hypoxemia in the fetus, and to facilitate timely delivery to avert academia, while correlating adverse perinatal outcomes with the severity of abnormalities in Doppler indices.

Study Design:

This is a prospective observational study conducted at the Department of Obstetrics and Gynecology, R.D. Gardi Medical College, Ujjain, from January 2023 to December 2024.

Study Population:

A total of 142 pregnant women diagnosed with pregnancy-induced hypertension (PIH) and/or intrauterine growth restriction (IUGR) were included in the study.

Inclusion Criteria:

• Singleton pregnancy between 28 to 40 weeks of gestation.
• Diagnosed with pregnancy-induced hypertension (PIH) and/or intrauterine growth restriction (IUGR).
• Patients willing to give informed consent for participation in the study.

Exclusion Criteria:

• Multiple pregnancies.
• Congenital anomalies detected in the fetus.
• Pre-existing maternal medical disorders (e.g., chronic hypertension, diabetes, renal disease).
• Patients not willing to participate or follow up.

Study Methodology:

1. Patient Enrollment and Grouping:
   • Pregnant women meeting the inclusion criteria were enrolled after obtaining informed consent.
   • Detailed history and clinical examination were conducted.
2. Investigations Conducted:
   • Color Doppler Ultrasound:
     • Performed to evaluate the following parameters:
       • Umbilical artery Doppler indices (Systolic/Diastolic ratio, Pulsatility Index, and Resistive Index).
       • Middle cerebral artery Doppler indices.
       • Cerebroplacental ratio.
     • Abnormal Doppler findings were recorded as absent/reversed end-diastolic flow in the umbilical artery, increased resistive indices, or abnormal cerebroplacental ratio.
   • Non-Stress Test (NST):
     • Conducted using a standard electronic fetal monitor for at least 20 minutes.
     • Categorized as:
       • Reactive (Two or more accelerations of at least 15 bpm lasting for at least 15 seconds in 20 minutes).
       • Non-reactive (No accelerations or insufficient accelerations).

3. Follow-up and Outcome Measures:
   • Patients were followed up until delivery.
   • Perinatal outcomes recorded included:
     • Birth weight.
     • Apgar score at 1 and 5 minutes.
     • Admission to Neonatal Intensive Care Unit (NICU).
     • Perinatal mortality (stillbirth or neonatal death within 7 days).

4. Statistical Analysis:
   • Data were entered and analyzed using appropriate statistical software.
   • Comparative analysis of the predictive value of Color Doppler and NST for adverse perinatal outcomes was conducted.
   • Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for both tests.
   • Chi-square test and Fisher's exact test were used for categorical variables.
   • A p-value of < 0.05 was considered statistically significant.

Ethical Consideration:

• Approval was obtained from the Institutional Ethics Committee of R.D. Gardi Medical College, Ujjain.
• Informed consent was obtained from all participants.

Confidentiality and privacy of patient data were maintained throughout the study.

Table 1: Distribution of Patients by Outcome

Out of 142 patients, 24.6% had NST results less than Doppler findings, while 59.2% showed equal results for both NST and Doppler. Meanwhile, 16.2% had NST outcomes greater than Doppler. This distribution illustrates a majority alignment between NST and Doppler results, with a smaller proportion showing discrepancies.

Table 2: Relation between Doppler Study and Perinatal Outcome

Out of 142 patients, abnormal Doppler findings were associated with abnormal perinatal outcomes in 75.8% of cases, whereas 24.2% had normal outcomes despite abnormal Doppler results. Conversely, normal Doppler findings correlated with normal perinatal outcomes in 81.5% of cases. The chi-square test result (χ² = 47.8, p = 0.000) indicates a statistically significant relationship between Doppler findings and perinatal outcomes.

Table 3: Relation Between NST and Perinatal Outcome

Out of 142 patients, non-reactive NST results were associated with abnormal perinatal outcomes in 73.8% of cases, while 26.2% had normal outcomes despite non-reactive results. In contrast, reactive NST findings were linked to normal perinatal outcomes in 69.3% of cases. The chi-square test (χ² = 28.1, p = 0.000) demonstrates a statistically significant association between NST results and perinatal outcomes.

table 4: Diagnostic Performance of NST and Doppler

In a study of 142 patients, NST showed moderate sensitivity and high specificity for most outcomes, with diagnostic accuracy ranging from 70.71% to 80.71%. In contrast, Doppler showed higher sensitivity but variable specificity, with diagnostic accuracy between 60% and 81.43%. Doppler demonstrated superior sensitivity for predicting neonatal mortality (100%), whereas NST showed better specificity across all outcomes.

Table 5: Comparison of Doppler study and NST.

In a comparison of Doppler study and NST across multiple studies, Trudinger et al. (n=170) reported a sensitivity of 17% for NST and 60% for Doppler, with Doppler showing a higher specificity (97%). Schulman’s study (n=180) found lower sensitivity for NST (7.6%) compared to Doppler (50%), but both showed high specificity (96% for NST and 97% for Doppler). William et al. (n=1360) demonstrated improved sensitivity for both NST (15%) and Doppler (68%), with Doppler maintaining high specificity (90%). In the present study of 142 patients, Doppler outperformed NST in sensitivity (75.4% vs. 50%) and had slightly lower specificity (82.2% vs. 87.3%), with positive predictive values of 76% for Doppler and 75% for NST, indicating overall better diagnostic performance for Doppler

High-risk pregnancies are characterised by an elevated risk of mortality or illness for the mother, foetus, or newborn. Pregnancy-induced hypertension and intrauterine growth restriction are primary contributors to perinatal death and morbidity. The obstetrician's responsibility involves rapid diagnosis and essential intervention, which necessitates both clinical acumen and trustworthy diagnostic methods. The determination for the prompt intervention during pregnancy relies on the comprehensive clinical assessment and particular outcomes of foetal evaluations, including aberrant foetal heart rate, Doppler examinations, and non-stress tests (NST).

A prospective observational study was performed in the department of obstetrics and gynaecology at Army Hospital Research and Referral in Delhi to compare the outcomes of non-stress tests (NST) with foetal Doppler velocimetry for predicting foetal outcomes in 140 singleton pregnancies affected by pregnancy-induced hypertension (PIH), intrauterine growth restriction (IUGR), or both conditions, during antenatal check-ups. Maternal age and gravida status In this study, the majority of patients (83.6%) were aged between 19 and 29 years. This indicates the reproductive duration of women with peak fertility and its correlation with risk factors such as PIH and IUGR within this age demographic. Upon examining the distribution of patients according on gravida, it was determined that the majority of patients were Primigravida constitutes 54.3%, and it is recognised that pregnancy-induced hypertension (PIH) is associated with primigravida. This population is more susceptible to obstetric problems. A comparable conclusion was noted in the study by Kumari et al., which indicated that PIH was prevalent among pregnant women under 25 years of age.[6] Zibaeenazhad et al. reported that primigravida under 20 years and all patients over 30 years have an elevated risk of hypertension.[7 ]Sheraz et al. similarly reported that preeclampsia is more prevalent in patients under 21 years of age and those over 35 years.[8] Gestational hypertension PIH was the predominant risk factor identified in 96 (68.5%) of the participants in this investigation. Among our patients with PIH, 40 out of 96 (41.66%) exhibited abnormally elevated waveform indices in the umbilical artery; two cases presented with absent end diastolic flow, and one case demonstrated reverse end diastolic flow. These discoveries closely align with Fleischer's findings, which indicated a S/D ratio exceeding 2.6 in the umbilical artery post 26 weeks in cases of PIH with compromised perfusion.[9] Among 96 instances, 28 exhibited non-reactive NST (29.16%), which was lower than the incidence of Doppler abnormalities (41.66%). Ozeren et colleagues conducted a cross-sectional study with 125 normal pregnancies and 62 preeclamptic patients at 31-40 weeks of gestation.[10]The umbilical artery S/D had the best sensitivity (88%) and diagnostic accuracy (94%) in forecasting unfavourable perinatal outcomes.

Intrauterine Growth Restriction (IUGR) In our study, 87 patients exhibited intrauterine growth restriction (IUGR), of whom 43 patients had concomitant pregnancy-induced hypertension. Out of 87 patients, 40 (45.97%) had abnormal Doppler waveform indices, while 47 patients (54.03%) demonstrated normal waveform values. Among 40 patients exhibiting aberrant waveform indices, one presented with REDF in the umbilical artery. Among 87 cases with IUGR, 23 (26.4%) exhibited non-reactive NST, whereas 64 cases (73.6%) demonstrated normal values.

A patient with REDF underwent an emergency caesarean surgery, resulting in the delivery of a preterm live asphyxiated infant (weight 1.2 kg, APGAR score 3/10 at 1 minute and 5/10 at 5 minutes), who subsequently died shortly after birth. This aligns with findings by Wang et al., indicating that reversed flow velocity in umbilical velocimetry signifies a grave concern.[11]

Radhika et al. noted in their research that 46% of the IUGR patients had aberrant Doppler studies, whereas 12.5% demonstrated non-reactive NST, closely paralleling our findings.[12] In a comparable study conducted by Tambat et al., among 70 patients with IUGR, 26 (37.14%) had aberrant Doppler waveforms, while 12 (17.14%) presented with non-reactive NST, corroborating the findings of our investigation.[13]

All 140 participants in this research underwent NST. Among 79 patients with favourable perinatal outcomes, 10 (12.5%) exhibited a non-reactive NST. Among the 61 patients with aberrant prenatal outcomes, 31 (50.8%) had reactive non-stress tests (NST). One patient with intrauterine foetal demise exhibited a reactive non-stress test during the past 48 hours. Other patients with newborn morbidity (five cases of RDS) also exhibited reactive NST prior to delivery. The false negative rate was 50.8%, the false positive rate was 12.5%, with sensitivity and specificity at 50.8% and 87.3%, respectively. In our study, the positive predictive value of NST is 75.05%, whereas the negative predictive value is 69.0%. Signore et al. reported a false negative rate of 0.2-1.2% and a false positive rate of 55-90%, which is not comparable to our findings.[14] This may have resulted from the absence of computerised examination of the foetal heart rate, which offers an objective evaluation of the CTG. In the study conducted by Ocak et al., they reported that the sensitivity and specificity of NST were 50% and 80%, respectively, in predicting perinatal outcomes, a finding that aligns with our results.[15]

Doppler examination In the current investigation, all 140 patients underwent Doppler velocimetry waveform analysis. Sixty patients exhibited an inappropriate S/D ratio on Doppler assessment. Among these 46 patients, 76.7% experienced adverse perinatal outcomes. The false negative rate was 24.5%, while the false positive rate was 17.7%. The false negative rate in the Doppler study was significantly lower compared to the NST. Doppler velocimetry exhibits a sensitivity of 75.4% and a specificity of 82.2%.

Exhibiting a positive predictive value of 76.6% and a negative predictive value of 81.2%, it demonstrates superiority over NST. Doppler velocimetry assessments of the umbilical artery can furnish obstetricians with crucial information pertaining to foetal well-being, hence enhancing foetal outcomes. Indiramani et al. noted that 45.7% of subjects with aberrant umbilical artery Doppler velocimetry waveforms experienced worse neonatal outcomes, corroborating the findings of our investigation.[16] In the research conducted by Subramanian et al., when both Doppler and non-stress tests yielded normal results, the majority of pregnancies exhibited favourable perinatal outcomes.[17] Conversely, when both Doppler and NST results were abnormal, approximately 53 percent of patients exhibited unfavourable perinatal outcomes.

Perinatal mortality The perinatal mortality rate in this study for high-risk women was 28.5 per 1000 live births (4 out of 140 cases). Adu-Bonsaffoh et al. reported a perinatal death rate of 15% (21 out of 140 hypertension patients), resulting in a perinatal mortality rate of 150 per 1,000 live births.[18] Alfirevic et al. reported a perinatal mortality rate of 143.7 per 1000 live births for infants weighing between 1.5 to 2.5 kg and born at a gestational age of less than 37 weeks, compared to 56.9 per 1000 live births for those born at a gestational age above 37 weeks.[19] The mortality rate was 746 per 1000 live births for infants weighing less than 1.5 kg.

Method of delivery In our study, aberrant Doppler readings were associated with a higher likelihood of caesarean delivery due to foetal distress (53% vs 37.5%) compared to normal Doppler readings. This study found that the caesarean section rate was elevated in cases with abnormal Doppler results. In the instance of non-reactive NST, the rate was 50%, but it was 42% in the reactive NST group. In the research by Jo et al., the caesarean section rate was 75% among patients with aberrant Doppler velocimetry, compared to 30% in the normal Doppler study group, which closely aligns with our findings.[20] Lohana et al. conducted an observational study revealing a caesarean rate of 46.66% in the non-reactive NST group, in contrast to 34% in the reactive NST group, which aligns with our findings.[21]

APGAR assessment In our study, 68.3% of patients with aberrant Doppler readings maintained an APGAR score of less than 7 at 5 minutes, in contrast to 10% of those with normal Doppler readings. as instances of non-reactive NST, 65% of patients exhibited an APGAR score of less than 7 at 5 minutes, as contrast to 22% in the reactive NST group. Doppler demonstrates greater sensitivity in predicting low APGAR scores, with a diagnostic accuracy of 81.43%, whereas NST attains a diagnostic accuracy of 74.29%. Tambat et al. discovered that 50% of patients in both the aberrant Doppler and non-reactive NST groups exhibited low APGAR scores at 5 minutes.[13] This is Marginally distinct from our observation, possibly attributable to variations in sample size. Chaudhary et al. noted that all patients with abnormal Doppler studies exhibited poor APGAR scores at 5 minutes.[22]

Neonatal Intensive Care Unit admittance In this study, 51.7% of infants born to patients with aberrant Doppler readings were admitted to the NICU, in contrast to 23.8% of cases with normal readings. In the instance of NST, the figure was 70% in contrast to 14%. Doppler demonstrates a sensitivity of 73.35% and specificity of 69.33%, whereas NST exhibits a sensitivity of 65.8% and specificity of 86.87%. In an observational study by Radhika et al., 73% of neonates in the aberrant Doppler study group required NICU hospitalisation, compared to 100% in the non-reactive NST group, which aligns with our findings.[12] In the study by Tambat et al, 66.7% of the aberrant Doppler study group required NICU admission, in contrast to 50% in the non-reactive NST group.[13] Perinatal results In our analysis, 76.7% of cases had adverse perinatal outcomes, including NICU admission (51.7%), jaundice (20%), MAS (5%), and RDS (26.7%), in contrast to 18.8% in patients with normal Doppler results. The statistical difference is highly significant (p<0.01). In instances of non-reactive NST, 75% exhibited poor perinatal outcomes, in contrast to 31% in the reactive NST group. Consequently, we can deduce that Doppler demonstrates superior sensitivity in identifying such situations, achieving a diagnostic accuracy of 79.29% compared to 70.71% for NST, according to our study. In our investigation, the sensitivity was 75.4% and the specificity was 82.2% for the Doppler, which closely aligns with the findings of Dathan et al., who reported 82.3%, Nagar et al., who reported 80%, and Trudinger et al.,[23-25] who reported 90%.Twenty to twenty-two In our investigation, the sensitivity of NST was 50% and the specificity was 87.3%. Choudhury et al. reported that the sensitivity and specificity of Doppler velocimetry were 43% and 100%, respectively, while the sensitivity and specificity of NST were 12% and 94%, respectively.[22] The sensitivity and specificity of Doppler blood flow were 75.4% and 82.2%, respectively, as indicated in Table 4 of this investigation, and these findings are close to those reported by Trudinger et al. and Schulman, as illustrated in Table 5.[25]. The sensitivity of the Doppler blood flow study, at 75.4%, is significantly higher than that of the NST, which is 50%. The overall diagnostic accuracy of Doppler is 79.29%, whereas that of NST is 70.71%, regarding the detection of unfavourable perinatal outcomes.

This study compared the diagnostic effectiveness of non-stress tests (NST) and Doppler velocimetry in predicting perinatal outcomes among high-risk pregnancies, particularly those complicated by pregnancy-induced hypertension (PIH) and intrauterine growth restriction (IUGR). The findings demonstrate that Doppler velocimetry has superior sensitivity (75.4% vs. 50%) and slightly lower specificity (82.2% vs. 87.3%) compared to NST. Doppler also showed higher diagnostic accuracy (79.29% vs. 70.71%) in predicting adverse perinatal outcomes, including low APGAR scores, NICU admissions, and neonatal morbidity.Abnormal Doppler findings were significantly associated with adverse perinatal outcomes (75.8%), whereas NST showed a higher false negative rate (50.8%). This indicates that Doppler is more reliable in identifying at-risk pregnancies. Additionally, Doppler demonstrated better predictive value for neonatal mortality and morbidity, highlighting its importance in clinical decision-making.The results emphasize that while NST is a valuable screening tool due to its high specificity, Doppler velocimetry is more effective in predicting adverse perinatal outcomes due to its higher sensitivity. Therefore, Doppler studies should be prioritized in monitoring high-risk pregnancies, especially when timely intervention is crucial. Combining both methods may enhance diagnostic accuracy and improve perinatal outcomes, guiding optimal obstetric management.

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