2.1. Study Design and Setting

This hospital-based retrospective study was conducted using medical data from the maternal birth register containing nulliparous, primiparous, and multiparous women who had singleton pregnancies from 1st January 2021 to 31st December 2021 to determine the gestational age–specific prevalence of PE and associated risk factors among pregnant women at HopeXchange Medical Centre, Kumasi.

HopeXchange Medical Centre is a modern, fully digital center of excellence with a 100-bed capacity. The medical center is one of the supporting hospital facilities to the Komfo Anokye Teaching Hospital (KATH), Ghana’s second largest hospital which is situated in the Ashanti Region of Ghana. This affiliation enhances its capacity to provide comprehensive maternal healthcare services in the region. It is situated at Wamase, Kumasi, in the Ashanti Region of Ghana. Wamase is a locality in Ghana. Wamase is situated nearby to the locality of Apere and the town of Aburaso. HopeXchange Medical Centre contains adult and pediatric wards, an intensive care unit, an outpatient center, three state-of-the-art surgical operating rooms, a clinical and research laboratory, a diagnostic and imaging department, an endoscopy unit, an ophthalmic department, and a maternal health unit.

2.2. Ethical Consideration

The study was approved by the Committee on Human Research, Publications and Ethics (CHRPE) (CHRPE/AP/621/23), School of Medicine and Dentistry, Kwame Nkrumah University of Science and Technology (KNUST). Written consent was requested from and approved by the Office of Research Support at HopeXchange Medical Centre. Strict measures ensured confidentiality and privacy, with anonymity and securely stored data accessible only to authorized researchers involved in this study.

2.3. Study Population and Participant Selection

Hospital records of 619 pregnant women aged 16–40 years who had singleton pregnancies from January 1, 2021, to December 31, 2021, at HopeXchange Medical Centre were obtained using an Excel spreadsheet from the hospital birth registry.

2.4. Inclusion Criteria and Exclusion Criteria

This study included all nulliparous, primiparous, and multiparous women who had singleton births at the hospital within the stated period, and all pregnancies at 20 weeks’ gestation to term. All nulliparous, primiparous, and multiparous women with gestational age less than 20 weeks, aged less than 15 years (< 15) and above 40 years (> 40), and with twin or multiple gestation were excluded.

2.5. Data Collection

Data was collected from the maternal birth register using an Excel spreadsheet which featured:

Sociodemographic variables (maternal age, occupation, and educational level), obstetric parameters (number of antenatal care (ANC) visits, gravidity, parity, gestational age, antepartum hemorrhage (APH), postpartum hemorrhage (PPH), etc.), maternal medical parameters (syphilis, hepatitis B, mother to child HIV transmission, hemoglobin concentration (HB), and intermittent preventive treatment in pregnancy with sulfadoxine–pyrimethamine (IPT/SP) medication), and labour variables (gender, weight, body length, head circumference (HC) and birth abnormality, fetal presentation and fetal lie, caesarean section or delivery through the birth canal, Apgar score, etc.). Missing data were excluded to prevent bias as their inclusion could compromise the study outcome.

PE was defined based on the revised definition by the International Society for the Study of Hypertension in Pregnancy (ISSHP) as a new onset of gestational hypertension (≥ 140 mmHg systolic/90 mmHg diastolic) developed at or after 20 weeks’ gestation and with new onset of at least either one of proteinuria (spot check urine protein > 30 mg/mmol (0.3 mg/mg) or > 300 mg/day or at least 1 g/L (“2+” using dipstick testing)) or without proteinuria but the involvements of maternal organ dysfunctions (neurological complications, pulmonary oedema, haematological complications, liver involvement, or acute kidney injury) and or uteroplacental dysfunction [9]. Diagnosis of PE was done by a consultant obstetrician and gynaecologist. Uteroplacental dysfunction was evaluated with ultrasound assessment of fetal growth and umbilical artery Doppler velocimetry or cerebroplacental ratio measurements to assess blood flow redistribution in placental insufficiency according to the International Society for Ultrasound in Obstetrics and Gynaecology guideline [10].

2.6. Statistical Analyses

The collected data obtained were entered, coded, edited, and cleaned in Microsoft Excel 2019. All statistical analyses were performed using the Statistical Package for the Social Sciences (SPSS) version 26.0 (Chicago Illinois, United States) and GraphPad Prism version 8.0.1 (GraphPad Software, San Diego California, United States, http://www.graphpad.com). Descriptive statistics were used to present the baseline data variables. Categorical data were presented as frequencies and percentages. The chi-square test/Fisher’s exact test and the univariate followed by multivariate logistic regression analysis were employed to test for associations and the strength thereof between the dependent variable (PE) and independent variables. The p values less than 0.05 were considered statistically significant for all analyses.

3.1. Sociodemographic and Maternal Obstetric Characteristics of Study Participants

Table 1 shows the demographic characteristics of the study participants. Out of the 619 study participants, 295 (47.7%) were aged 20–29 years, while only 16 (2.6%) were 40 years. Thirteen (2.1%) of the women had no formal education, but the majority had acquired basic education (226, 36.7%), 168 (27.3%) had secondary education, and 209 (33.9%) had tertiary education. Also, 346 (56.7%) of the pregnant women worked in the informal sector, as compared to 197 (32.3%) who were employed in the formal sector. Furthermore, multigravida (372, 60.4%) accounted for the majority of pregnant women, followed by grand multigravida (131, 21.3%) and primigravida (113, 18.3%). The majority of the pregnant women were multiparous (259, 42.0). More than half of the women (536, 96.4%) had ≥ 4 ANC visits (Table 1).

3.2. Overall Prevalence of PE Among the Study Participants

Figure 1 shows the overall prevalence of PE among the study participants. The prevalence of PE among the study participants was 10.5% (65/619) whereas 80.5% (554/619) were normotensive pregnant women (NTM) (Figure 1).

3.3. Gestational Age–Specific Prevalence of PE Among the Study Participants

The distribution of women according to their gestational age–specific prevalence of PE is shown in Figure 2. The prevalence of PE was 2.3%, 2.1%, 4.0%, 1.6%, and 0.5% at < 37 weeks, 37–38 weeks, 39–40 weeks, 41 weeks, and ≥ 42 weeks, respectively (Figure 2).

3.4. Association of Sociodemographic and Maternal Obstetric Characteristics With PE Among Study Participants

Table 2 shows the association of maternal demographic characteristics and obstetric factors with PE among study participants. There was no significant association between participants’ level of education (p = 0.6830), occupation (p = 0.4210), ANC visit (p = 0.0930), gravidity (p = 0.2350), parity (p = 0.2110), anaemia status (p = 0.3230), and PE. However, PE was found to be significantly associated with gestational age category (< 37, 37–38, 39–40, ≥ 40, and ≥ 42) (p = 0.0001) and age category (p = 0.0230) (Table 2).

3.5. Association of Adverse Foetomaternal Complications With PE Among the Study Participants

Table 3 shows the association of adverse maternal complications with PE among the study participants. There was no birth asphyxia in a greater percentage (98.5%) of the pregnant women with PE. PE was present in 100% of the mothers, who all gave birth to live babies. There was no significant association between birth asphyxia (p = 0.8500), birth abnormalities (p = 0.1970), prolonged labour (p = 0.1420), PPH (p = 0.3640), APH (p = 0.3340), obstructed labour (p = 0.1420), birth outcome (p = 0.4180), and state of placenta (p = 0.1420) with PE. This study found a significant association between mode of delivery (p = 0.0001) and PE (Table 3).

3.6. Association of Labour Characteristics With PE Among the Study Participants

Table 4 shows the association of labour characteristics with PE among the study participants. Both groups (PE and NTM) had a higher percentage of male births (56.5% vs. 56.9%) than female births (43.5% vs. 43.1%). The study found no significant association between baby sex (p = 0.9530), full length (p = 0.2970), 1-min Apgar score (p = 0.8380), and 5-min Apgar score (p = 0.5670) with PE. However, a significant association between weight (p = 0.0290), HC (p = 0.0430), and PE were found (Table 4).

3.7. Univariate and Multivariate Logistic Regression Model of Sociodemographic, Obstetric, and Labour Characteristics and Maternal Complication Predictors of PE Among Study Participants

Table 5 shows the maternal sociodemographic, obstetric, and labour characteristics and maternal complications as predictors of PE among the study participants. In a univariate logistic regression model, age category, mode of delivery, fetal gestational age category, weight, and HC were predictors of PE. Women between 30 and 39 years (crude odds ratio (cOR) = 2.39, 95% confidence interval (CI) (1.34–4.24), p = 0.0030) were significantly associated with 2.3 times higher risk of being diagnosed with PE when compared with women between 20 and 29 years. Also, women who underwent previous caesarean section (cOR = 3.01, 95% CI (1.73–5.22), p = 0.020) were significantly associated with a 3.0 times increased risk of being diagnosed with PE compared with normal delivery. Women with gestational age < 37 weeks (cOR = 0.18, 95% CI (0.07–0.45), p ≤ 0.0001), 37–38 weeks (cOR = 0.15, 95% CI (0.06–0.33), p ≤ 0.0001), and ≥ 42 weeks (cOR = 0.27, 95% CI (0.10–0.71), p = 0.0080) had lower odds of having PE compared with those with a gestational age of 39–40 weeks. Moreover, low baby weight (cOR = 2.69, 95% CI (1.27–5.73), p ≤ 0.0100) was significantly associated with 2.6 times of being diagnosed with PE than normal weight. HC < 33 (cOR = 1.84, 95% CI (1.01–3.33), p ≤ 0.0450) was significantly associated with 1.8 times the risk of being diagnosed with PE as compared to HC ≥ 33.

After adjusting for the level of education and occupation in a multivariate logistic regression model, having age group 30–39 years (aOR = 2.49, 95% CI (1.25–4.96), p = 0.0090), having C/S (aOR = 2.83, 95% CI (1.46–5.50), p = 0.0020), and having gestational age category < 37 weeks (aOR = 0.24, 95% CI (0.07–0.78), p = 0.0140) and 37–38 weeks (aOR = 0.23, 95% CI (0.08–0.66), p = 0.0060) remained significant and were the independent predictors of PE and having HC < 33 (aOR = 2.09, 95% CI (1.00–4.37), p = 0.0490) was the independent complication associated with it (Table 5).

5.1. Recommendation

Based on the study findings, the following are recommended.

It is recommended that health workers use maternal age, previous caesarean section, and gestational age, as screening tools for the prediction of PE in the study setting as early as possible which will also help manage and prevent complications such as small fetal HC associated with it.

5.2. Strengths and Limitations of the Study

The use of gestational age in this study helped to assess the prevalence of PE.

This study has its limitations, even though it provides policymakers with information to help reduce morbidity and mortality from PE. Since secondary data were used, some records about sociodemographic, obstetric, medical, and fetal features were missed.