Fetal monitoring plays a pivotal role in modern obstetric care, especially for pregnancies at risk of complications. Among the various diagnostic tools available, Doppler ultrasonography has become essential in assessing fetal well-being, providing valuable insights into fetal circulation and hemodynamics. The ductus venosus, a key vessel in fetal circulation, serves as a conduit for oxygenated blood from the placenta to the fetal heart. The pulsatility index (PI) of the ductus venosus, measured via Doppler ultrasound, has been widely studied as a potential marker for predicting adverse pregnancy outcomes.

Abnormalities in the ductus venosus PI, such as an elevated index, are associated with fetal compromise, including conditions like intrauterine growth restriction (IUGR), preeclampsia, and fetal distress. These complications, if not detected early, can lead to significant maternal and fetal morbidity and mortality. As a result, the ductus venosus PI offers a promising approach for the early identification of pregnancies at risk of these adverse outcomes. It provides an important advantage in cases where other clinical signs or symptoms may not yet be evident, allowing for earlier intervention and better management of at-risk pregnancies.

This study aims to evaluate the predictive value of the ductus venosus pulsatility index in early pregnancy. By investigating the relationship between changes in the PI during the first and second trimesters and the occurrence of complications such as preterm birth and IUGR, the study seeks to establish the ductus venosus Doppler as a reliable, non-invasive tool for assessing pregnancy risk

This prospective cohort study was conducted to evaluate the predictive value of the ductus venosus pulsatility index (PI) in early pregnancy for adverse pregnancy outcomes. The study took place from January 2023 to July 2023 at a tertiary care hospital, with a sample size of 70 pregnant women who met the inclusion criteria. Ethical approval for the study was obtained from the institutional research committee. The study adhered to ethical guidelines, and informed consent was secured from all participants prior to their inclusion in the research.

The study population consisted of 70 pregnant women attending prenatal care at the hospital during the specified study period. Inclusion criteria required participants to have singleton pregnancies with gestational ages between 11 and 20 weeks. Women with significant medical or obstetric conditions that could affect the study outcomes, as well as those with contraindications to Doppler ultrasonography such as fetal anomalies or severe fetal compromise in previous pregnancies, were excluded from the study. All participants provided written informed consent prior to enrollment.

Doppler ultrasonography was performed on each participant during routine prenatal visits by a trained sonographer. The ductus venosus PI was measured to assess fetal circulation and its potential correlation with adverse pregnancy outcomes. Doppler measurements were obtained by analyzing the ductus venosus waveform to determine the peak systolic velocity (PSV), end-diastolic velocity (EDV), and their relationship, which were then used to calculate the PI. The PI was used as the primary variable for the study to determine its predictive ability for complications such as intrauterine growth restriction (IUGR), preterm birth, preeclampsia, and fetal distress.

The women were followed until delivery to assess pregnancy outcomes. The primary outcomes evaluated included IUGR, defined as a birth weight below the 10th percentile for gestational age; preterm birth, defined as delivery before 37 weeks of gestation; preeclampsia, characterized by high blood pressure (≥140/90 mm Hg) and proteinuria after 20 weeks of gestation; and fetal distress, identified by abnormal fetal heart rate patterns or other signs of fetal hypoxia during labor.

Statistical analysis was conducted to examine the correlation between the ductus venosus PI and adverse pregnancy outcomes. Descriptive statistics were used to summarize the demographic and clinical characteristics of the participants. Sensitivity, specificity, positive predictive value, and negative predictive value of the ductus venosus PI in predicting these outcomes were calculated. The relationship between PI values and pregnancy complications was assessed using appropriate statistical tests, such as chi-square tests for categorical variables and t-tests for continuous variables.

Statistical analysis   

The recorded data was compiled and entered in a spreadsheet computer program (Microsoft Excel 2019) and then exported to data editor page of SPSS version 19 (SPSS Inc., Chicago, Illinois, USA). Quantitative variables were described as means and standard deviations or median and interquartile range based on their distribution. Qualitative variables were presented as count and percentages. For all tests, confidence level and level of significance were set at 95% and 5% respectively

Table 1 summarizes the demographic data of the study group, including 70 participants. The age distribution shows 20% are under 25, 30% are between 25-30, and 22% are over 30, with a mean age of 28.5 years. Regarding marital duration, 17.1% have been married for less than 2 years, 45.7% for 3-5 years, and 14.3% for more than 5 years, with a mean duration of 3.75 years.

Table 2 presents the distribution of pregnancy outcomes among the 70 study participants. The majority of pregnancies resulted in normal outcomes (85.7%). Among the abnormal outcomes, 4.3% had congenital heart defects, 2.9% had congenital malformations (trisomy 21), 5.7% had low birth weight, and 1.4% resulted in stillbirth.

Table 3 compares the basic demographic and maternal data between the normal (n=60) and abnormal (n=10) pregnancy outcome groups. The data includes age range, mean age, standard deviation (SD) of age, duration of marriage, and gestational age (G.A.). The mean age of the normal group is slightly higher than the abnormal group, with the normal group also showing a wider range in both age and marriage duration. The gestational age at the time of evaluation is higher in the normal outcome group. The table also includes t-test p-values for each category, indicating no significant differences between the two groups in the assessed parameters.

Table 4 compares ultrasound findings between the normal (n=60) and abnormal (n=10) pregnancy outcome groups. It includes the pulsatility index (PI) and the systolic-to-diastolic (S/a) ratio. The normal group has a higher mean PI (0.92), and a wider range (0.80-1.30) compared to the abnormal group, which has a lower mean PI (0.51) and a narrower range (0.45-0.55). The S/a ratio is also higher in the normal group (mean 2.25) compared to the abnormal group (mean 1.85), with significant differences indicated by the t-test p-values.

Table 5 compares various pregnancy history factors between the normal (n=60) and abnormal (n=10) pregnancy outcome groups. It includes factors such as the regularity of the menstrual cycle, previous placenta previa, history of ectopic pregnancies, present and past obstetric problems, contraceptive history, and family history. The percentages for each category are presented, along with the chi-square (χ2) test values and p-values, which show no significant differences between the two groups for most variables, as indicated by the non-significant p-values.n

Table 1: Demographic data of the study group.

Table 2: Distribution of the studied groups regarding the outcome of pregnancy.

  Table 3: Comparison between outcome of pregnancy with basic demographic and maternal data.

Table 4: Comparison between outcomes of pregnancy with ultrasound findings.

Table 5: Comparison between outcomes of pregnancy with pregnancy outcome.

This study aimed to evaluate the role of Doppler ultrasonography, specifically the ductus venosus pulsatility index (PI), in predicting adverse pregnancy outcomes in a cohort of 70 pregnant women. The findings from this study reinforce the growing body of evidence supporting the utility of Doppler indices as reliable markers for identifying pregnancies at risk for complications such as intrauterine growth restriction (IUGR), preterm birth, and fetal distress.

The results demonstrated significant differences in the ductus venosus PI between normal and abnormal pregnancy outcomes, with the abnormal group exhibiting a markedly lower PI. This finding is consistent with previous studies that have highlighted the ductus venosus PI as a potential early indicator of fetal compromise. Elevated PI values have been associated with poor pregnancy outcomes, such as IUGR and preeclampsia, as higher resistance in the ductus venosus indicates potential fetal hypoxia and poor placental perfusion (10).

The predictive value of Doppler ultrasonography in detecting fetal distress and other adverse outcomes was further supported by our analysis of the systolic-to-diastolic (S/a) ratio. In line with other studies, a lower S/a ratio was observed in the abnormal group, indicating impaired fetal circulation and the potential for future complications (11). These findings emphasize the importance of early detection, which could allow for interventions that may prevent or mitigate the severity of adverse pregnancy outcomes (12).

Moreover, the comparison between pregnancy outcomes and maternal history revealed no significant differences for most variables, including the regularity of the menstrual cycle, history of ectopic pregnancy, and contraceptive history. This suggests that while Doppler indices may provide important insights into fetal well-being, maternal history alone may not be sufficient for predicting complications in all cases (13).

The sensitivity and specificity of the ductus venosus Doppler in predicting adverse outcomes is a critical factor in clinical decision-making. Previous studies have demonstrated that abnormal Doppler results can guide the management of high-risk pregnancies, offering a non-invasive method for fetal monitoring that complements other clinical tools such as ultrasound imaging and fetal heart rate monitoring (14). However, the use of Doppler ultrasonography as a standalone predictor of pregnancy outcomes remains an area for further exploration, as the results can be influenced by a variety of factors, including maternal health, fetal positioning, and operator skill (15).

In conclusion, our study reaffirms the importance of Doppler ultrasonography, particularly the ductus venosus PI, as a valuable tool in the early identification of pregnancies at risk for adverse outcomes. While the results were promising, further studies with larger sample sizes are needed to better define the role of Doppler indices in routine prenatal care and to establish standardized protocols for their use in clinical practice.

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