Hypertensive disorders of pregnancy (HDP) constitute one of the leading causes of maternal and perinatal morbidity and mortality globally, accounting for approximately 14% of maternal deaths in low- and middle-income countries [1]. HDP is an umbrella term that includes gestational hypertension, preeclampsia–eclampsia, chronic hypertension, and chronic hypertension with superimposed preeclampsia [2]. These conditions are associated with serious maternal complications such as placental abruption, stroke, and multi-organ failure, as well as adverse neonatal outcomes including preterm birth, intrauterine growth restriction (IUGR), low birth weight, and stillbirth [3,4].

Preeclampsia, a multisystem disorder characterized by new-onset hypertension and proteinuria or end-organ dysfunction after 20 weeks of gestation, is the most clinically significant form of HDP and affects approximately 2–8% of pregnancies worldwide [5,6]. Its pathophysiology involves abnormal placentation, endothelial dysfunction, and exaggerated systemic inflammatory responses, leading to impaired uteroplacental blood flow and subsequent fetal compromise [7,8].

The impact of HDP on neonatal outcomes is profound. Studies have consistently shown increased risks of prematurity, NICU admission, and perinatal mortality among neonates born to mothers with hypertensive disorders [9]. These risks are particularly elevated in severe preeclampsia, where early delivery is often required to safeguard maternal health, albeit at the expense of gestational age.

Despite advances in antenatal care and the availability of screening tools, delayed diagnosis and inadequate monitoring remain challenges in resource-limited settings. Early identification and close maternal-fetal surveillance are crucial in reducing complications. Understanding the local incidence and pattern of neonatal outcomes associated with HDP is essential to guide clinical protocols and resource allocation.

The present study was undertaken to estimate the incidence of HDP in a tertiary care hospital and evaluate its association with adverse neonatal outcomes, with the aim of contributing to improved perinatal management strategies.

Study Design and Setting

A prospective observational study was carried out in the Department of Obstetrics and Gynaecology at a tertiary care teaching hospital over a period of 12 months.

Study Population

All pregnant women beyond 20 weeks of gestation who attended the antenatal clinic or were admitted for delivery during the study period were screened for hypertensive disorders of pregnancy (HDP) according to the American College of Obstetricians and Gynecologists (ACOG) guidelines.

Sample Size and Sampling Method
A total of 620 pregnant women were enrolled using a consecutive sampling approach. The sample size was calculated assuming an anticipated incidence of HDP of 10%, a 95% confidence interval, and a 3% margin of error.

Inclusion Criteria

• Pregnant women ≥20 weeks of gestation
• Willing to provide informed consent
• Diagnosed with gestational hypertension, preeclampsia–eclampsia, chronic hypertension, or chronic hypertension with superimposed preeclampsia as per ACOG criteria

Exclusion Criteria

• Multiple pregnancies
• Known chronic medical disorders unrelated to hypertension (e.g., cardiac, renal, or hepatic disease)
• Major fetal anomalies detected antenatally

Diagnosis and Classification

HDP was classified as:

1. Gestational hypertension: Blood pressure ≥140/90 mmHg on two occasions at least 4 hours apart after 20 weeks of gestation, without proteinuria.
2. Preeclampsia: Hypertension after 20 weeks with proteinuria (≥300 mg/24 hours) or evidence of end-organ dysfunction.
3. Eclampsia: Preeclampsia with seizures not attributable to other causes.
4. Chronic hypertension with superimposed preeclampsia: Pre-existing hypertension before pregnancy or before 20 weeks, with subsequent development of preeclampsia.

Data Collection

Maternal demographic data, obstetric history, type of HDP, and gestational age at delivery were recorded. Neonatal outcomes assessed included birth weight, gestational age, Apgar score at 5 minutes, NICU admission, and stillbirth. Birth weight <2.5 kg was considered low birth weight, and gestational age <37 weeks was defined as preterm.

Statistical Analysis

Data were entered into Microsoft Excel and analysed using SPSS version 26.0 (IBM Corp., Armonk, NY, USA). Continuous variables were expressed as mean ± standard deviation (SD), and categorical variables as frequencies and percentages. Chi-square or Fisher’s exact tests were applied to evaluate associations between HDP subtypes and neonatal outcomes. A p-value <0.05 was considered statistically significant.

A total of 620 pregnant women were included in the study. The mean maternal age was 27.9 ± 4.6 years, with the majority in the 21–30 years age group (65.3%). The overall incidence of hypertensive disorders of pregnancy (HDP) was 11.9% (n = 74).

Distribution of HDP Subtypes

Preeclampsia was the most common subtype, affecting 54.1% of HDP cases, followed by gestational hypertension (33.8%) and chronic hypertension with superimposed preeclampsia (12.1%) (Table 1).

Table 1. Distribution of hypertensive disorders of pregnancy (n = 74)

Neonatal Outcomes

Among women with HDP, preterm birth occurred in 41.9% of cases, while 48.6% delivered low birth weight (LBW) infants. NICU admission was required for 35.1% of newborns, and stillbirth occurred in 6.8% of cases (Table 2).

Table 2. Neonatal outcomes among mothers with HDP (n = 74)

Association Between HDP Subtype and Neonatal Outcomes

Severe preeclampsia cases showed a significantly higher incidence of LBW (62.5%) and NICU admission (47.5%) compared to gestational hypertension and chronic hypertension with superimposed preeclampsia (p<0.05) (Table 3).

Table 3. Association of HDP subtypes with selected neonatal outcomes

*Chi-square test; * statistically significant

In summary, HDP was significantly associated with preterm birth, LBW, NICU admission, and stillbirth. The most adverse neonatal outcomes were observed in severe preeclampsia cases (Tables 1–3).

The present study found an incidence of hypertensive disorders of pregnancy (HDP) of 11.9%, which is in line with previous Indian studies reporting rates between 7% and 15% [1,2]. Preeclampsia emerged as the predominant subtype (54.1%), consistent with global and national data indicating it as the most common clinically significant form of HDP [3,4]. The relatively high proportion of preeclampsia cases in this study may be attributed to referral bias, as tertiary centres often manage more severe cases.

Neonatal outcomes in our cohort were markedly affected by HDP, with preterm birth in 41.9% and low birth weight (LBW) in 48.6% of cases. These findings corroborate earlier reports where compromised uteroplacental perfusion in HDP led to intrauterine growth restriction and indicated preterm delivery [5,6]. The association of severe preeclampsia with the highest rates of LBW (62.5%) and NICU admission (47.5%) underscores the critical role of disease severity in determining perinatal outcomes [7,8].

NICU admissions were required in 35.1% of neonates, primarily for complications such as respiratory distress and birth asphyxia. Similar admission rates have been observed in other tertiary hospital studies [9,10]. The observed stillbirth rate of 6.8% among HDP cases is higher than that in the general obstetric population, reflecting the impact of placental insufficiency and fetal compromise in these pregnancies [11].

The pathophysiology underlying these adverse outcomes involves abnormal trophoblastic invasion, endothelial dysfunction, and increased vascular resistance, leading to chronic fetal hypoxia and nutritional deprivation [12]. This biological mechanism explains why even well-monitored pregnancies with HDP remain at elevated risk for growth restriction and preterm birth despite timely interventions.

The high incidence of preterm delivery in our study aligns with the practice of planned early delivery in severe HDP to prevent maternal complications such as eclampsia, HELLP syndrome, and placental abruption [13,14]. However, this often comes at the cost of prematurity-related neonatal morbidity, emphasizing the need for a careful balance between maternal safety and neonatal maturity.

Our findings highlight the importance of early detection, close maternal-fetal surveillance, and timely referral to tertiary care facilities for optimal outcomes. Implementation of standardized antenatal screening protocols and enhanced community awareness could contribute to early diagnosis and management of HDP [15].

Hypertensive disorders of pregnancy significantly increase the risk of adverse neonatal outcomes, particularly preterm birth, low birth weight, and NICU admission, with the greatest impact seen in severe preeclampsia. Early detection, close monitoring, and timely intervention are essential to improving perinatal survival and reducing morbidity.

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