1. Introduction

Preeclampsia, a major contributor to maternal and perinatal morbidity and mortality, presents a significant global health challenge, with a disproportionate impact on low- and middle-income countries like Bangladesh [1,2]. The rising incidence of hypertensive disorders of pregnancy in Bangladesh underscores the urgent need to identify early predictive factors [3]. While the pathophysiology of preeclampsia is multifactorial [4], hormonal imbalances are increasingly implicated [5]. Beyond the well-established role of the renin-angiotensin system, the involvement of androgens, including testosterone, is gaining attention [5]. Specifically, free testosterone, the biologically active fraction, may be altered in preeclamptic pregnancies [6,7]. Studies from various regions, including the Indian subcontinent and Russia, have explored the association between androgens and preeclampsia [8,9,12,14]. Furthermore, research has examined the broader role of androgens in both normal pregnancy and preeclampsia [13,15]. Studies conducted in India have specifically reported on maternal testosterone levels in preeclampsia [8,9]. Clinical guidelines from international organizations emphasize the importance of understanding the pathophysiology of preeclampsia for improved management [10,11]. This study aimed to determine the relationship between serum free testosterone levels and the occurrence of preeclampsia in pregnant women between 20 and 40 weeks of gestation at a tertiary care hospital in Dhaka, Bangladesh.

2. Materials and Methods

This case-control study was conducted at the BMU, Dhaka, Bangladesh, from September 2021 to August 2022. It included 39 primigravid women with preeclampsia and 39 normotensive controls, matched for gestational age (20–40 weeks), selected via purposive sampling.

Cases met criteria for blood pressure ≥140/90 mmHg (on at least two occasions, four hours apart), proteinuria ≥0.3 g/L, or systemic signs of preeclampsia. Controls were normotensive primigravid women with singleton pregnancies. Exclusion criteria included pre-existing hypertension, systemic diseases, prior antihypertensive or hormone use, hormonal disorders (e.g., polycystic ovary syndrome), psychotic conditions, and smoking.

After informed consent, socio-demographic, anthropometric, and obstetric data were collected via questionnaire. Blood pressure was measured in the supine position, and BMI was calculated. Midstream urine samples were tested for proteinuria, and 5 mL venous blood samples were analyzed for serum free testosterone levels using the DRG free Testosterone ELISA kit at BMU.

Data analysis was performed using International Business Machines Corporation IBM SPSS Statistics version 26, employing descriptive and inferential statistical tests.

2.1 Data processing plan (Figure 1)

Figure 1: Data processing plan.

3. Results

The study included 78 pregnant women, equally divided into preeclampsia (cases) and control groups. Urban residency was more common among 87.2% than controls 69.2%. Age distribution was similar, with slightly more women aged 40+ in the control group 43.6% vs. 33.3%. Higher education (higher secondary or above) was lower in cases 20.5% compared to controls 51.3%. Most cases were housewives 82.1% versus 53.8% in controls, who had more service holders 23.1% and businesswomen 17.9%. Family income above 50,000 BDT was reported by fewer cases 7.7% than controls 28.2%.

Obesity was more frequent in cases 56.4% than controls 46.2%. Moderate to severe edema was more common in cases 41.0% than controls 23.1%. Primigravida and primipara status were higher in the case group 79.5% and 82.1% compared to controls 41.0% and 61.5%. Gestational age was mostly 30–36 weeks in cases 56.4% and 36–40 weeks in controls 66.7%.

Medical history showed that hypertension 7.7%, prior preeclampsia 5.1%, family history of hypertension 12.8%, and preeclampsia 2.6% were less frequent in cases than controls (20.5%, 12.8%, 23.1%, and 10.3%, respectively). Gestational diabetes was also lower in cases 15.4% than controls 25.6%.

Vitamin D supplementation was higher in cases 64.1% than controls 51.3%. Sunlight exposure over 30 minutes was more common in cases 41.0% than controls 28.2%, while 15–30 minutes was higher in controls 43.6%. Moderate physical activity was more frequent among cases 53.8% and mild activity among controls 59.0%. Dairy intake was evenly distributed among cases; controls had a slightly higher proportion reporting low intake 38.5%.

Proteinuria was more severe in cases, with 33.3% showing ++ and 15.4% +++ levels, compared to 23.1% and 12.8% in controls. Negative results were lower in cases 17.9% than in controls 28.2%. Similar trends were seen in urine protein status.

A significant association was found between serum free testosterone levels and preeclampsia (p = 0.030), with high levels in 48.7% of cases versus 41.0% of controls.

Table 1: Socio-demographic characteristics of respondents by group classifications (Case vs Control).

Table 1 shows among women with preeclampsia (Case), 87.2% resided in urban areas compared to 69.2% of controls. Age distribution was similar, though 43.6% of controls were aged 40+ versus 33.3% in cases. Educationally, only 20.5% of cases had higher secondary or above, compared to 51.3% of controls. Most cases were housewives (82.1%), while controls had more service holders (23.1%) and businesswomen (17.9%). Family income was lower among cases, with 25.6% earning <30,000 BDT and only 7.7% earning >50,000 BDT, compared to 15.4% and 28.2% in controls, respectively.

Table 2: Distribution of Health and Obstetric Profile of Respondents by Group Classification (Preeclampsia vs. Control).

Table 2 illustrates obesity was more common among pre-eclampsiacases at 56.4% than controls 46.2%, while normal BMI was slightly higher in controls 41.0% vs. 35.9%. Edema severity was greater in cases, with only 12.8% showing no edema compared to 23.1% in controls, and 17.9% of cases had severe edema versus 12.8% in controls. Most cases were primigravida 79.5% and primipara 82.1%, in contrast to 41.0% and 61.5% in the control group, respectively. Gestational age at data collection was mostly 30–36 weeks in cases 56.4%, while 66.7% of controls were in the 36–40 weeks range.

Table 3: Distribution of Respondents by Previous Medical and Family History (Preeclampsia vs. Control).

Table 3 displays a smaller proportion of pre-eclampsia cases had a history of hypertension 7.7% compared to controls 20.5%. Similarly, history of preeclampsia 5.1% vs. 12.8% and family history of both hypertension 12.8% vs. 23.1% and preeclampsia 2.6% vs. 10.3% were all less common among cases than controls. The history of gestational diabetes was also lower in 15.4% than in controls 25.6%.

Figure 2: Behavioral Characteristics of Respondents by Group.

Figure 2 displays vitamin D supplementation was slightly more common among cases 64.1% than controls 51.3%. Sunlight exposure over 30 minutes daily was higher in the case group 41.0% than in controls 28.2%, though controls had more in the 15–30-minute range 43.6% vs. 35.9%. Physical activity levels were similar, with more moderate activity in cases 53.8% and more mild activity in controls 59.0%. Dairy intake was evenly distributed among cases 33.3% across all frequencies), while controls had a slightly higher percentage reporting low intake 38.5% and fewer consuming dairy more than 5 times weekly 28.2%.

Table 4: Laboratory Investigation Findings (Proteinuria) Among Respondents by Group Classification.

Table 4 shows proteinuria severity was higher among preeclampsia cases, with 33.3% showing ++ and 15.4% +++, compared to 23.1% and 12.8% in controls, respectively. Fewer cases were negative for proteinuria 17.9% versus controls 28.2%. In urine protein status, 12.8% of cases had 1+ and 2.6% had 2+, while 56.4% tested negative and 28.2% had trace amounts. Among controls, 61.5% were negative, 23.1% had trace, and 7.7% each had 1+ and 2+, indicating milder proteinuria in the control group.

*ᵪ² test was done. *Level of significance p=<0, 05 at 95% CI.

Table 5: Association between Serum Free Testosterone Levels and preeclampsia.

Table 5 demonstrates high serum free testosterone levels were more prevalent among women with preeclampsia 48.7% compared to controls 41.0%, with a statistically significant association observed between testosterone levels and preeclampsia p = 0.030, suggesting a potential hormonal link to the condition.

4. Discussion

This study demonstrated a statistically significant association between elevated serum free testosterone levels and the occurrence of preeclampsia (p = 0.030), with a greater proportion of affected women exhibiting high levels compared to normotensive controls. These findings align with previous studies from the Indian subcontinent and other regions, including a recent meta-analysis that supports a hormonal contribution to preeclampsia pathogenesis [8,9,20]. Venkatesha et al. [8] and Jain et al. [9] reported elevated maternal total testosterone levels in preeclamptic women, reinforcing our observation that the biologically active free testosterone fraction may play a more direct role in disease development.

Free testosterone, as measured in our study, represents an unbound, physiologically active form capable of exerting vascular and placental effects. Previous research has highlighted its influence on endothelial function and trophoblast invasionkey mechanisms in preeclampsia pathophysiology [6,7]. Moreover, a growing body of evidence supports the interplay between the androgen pathway and angiogenic imbalance in preeclampsia, complementing the traditionally emphasized roles of the renin-angiotensin system and anti-angiogenic factors [5,15].

The high burden of preeclampsia in low- and middle-income countries, particularly in Bangladesh and across the Indian subcontinent, underscores the need for locally relevant biomarkers and early predictors [2,3]. Our findings contribute to this understanding by providing evidence from a Bangladeshi cohort, aligning with national studies that have also reported elevated free testosterone levels in preeclamptic pregnancies [18,19]. These results suggest the potential of free testosterone as a biomarker for early identification of preeclampsia risk in resource-limited settings.

Additionally, socio-demographic differences observed in our study such as higher rates of urban residency, lower educational attainment, and lower income among pre-eclampsia casesare consistent with known risk factors for adverse pregnancy outcomes [16,17]. While our primary focus was the hormonal association, future research should explore how these social determinants may interact with endocrine pathways, including androgen metabolism, in the development of preeclampsia.

5. Conclusion

This study identified a significant association between elevated serum free testosterone levels and the occurrence of preeclampsia among primigravid women in Bangladesh. The findings support growing evidence that androgens, particularly free testosterone, may contribute to the pathophysiology of pre-eclampsia by influencing vascular and placental function. Given the high burden of hypertensive disorders in pregnancy in low- and middle-income countries, serum free testosterone may serve as a promising biomarker for early identification and risk stratification of preeclampsia. Future large-scale, prospective studies are recommended to validate these findings and explore their clinical utility in maternal health interventions.

Declaration of Interest

The authors declare no competing interests.

Conflict of Interest

The authors have no conflicts of interest to disclose related to this study.

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