Latent profiles and associated factors of body image in pregnant women

Study design and setting

This cross-sectional observational study utilized convenience sampling to recruit pregnant women from the Obstetrics Ward and Perinatal Health Department of the Affiliated Hospital of Zunyi Medical University, located in Zunyi City, Guizhou Province, China. The study was conducted from December 2023 to April 2024. The inclusion criteria comprised primigravid women aged between 18 and 45 years and a gestational age ranging between 30–37 weeks. Women with or undergoing treatment for any preexisting medical, surgical, or psychiatric illness were excluded from the study to minimize confounding factors.

Data collection

Three researchers independently conducted face-to-face data collection. Participants fulfilling the inclusion criteria were provided with detailed information regarding the nature of the study, purpose, and investigation procedures. All participants signed the informed consent form prior to participating in the study. A research questionnaire was developed using the Questionnaire Star platform by incorporating the relevant survey items, variables, and questions into the template. All questions were pre-tested to ensure accuracy and clarity. Participants accessed the questionnaire via a code or link generated by the platform. While the participants were completing the questionnaire, one researcher monitored the questionnaire filling status. To minimize invalid responses, incorrect or incomplete responses were reviewed and addressed in real time.

Sample calculation

The sample size for this cross-sectional study was calculated using PASS 15.0 software. According to previous studies, the prevalence of body image dissatisfaction in pregnant women was estimated at 34.1%⁶. With a 90% confidence level and a confidence interval width of 10%, the sample size was determined to be 262 patients. Considering a non-response rate of 20%, the sample size was adjusted to 328 individuals.

Measures

The self-administered questionnaire included items evaluating demographic characteristics (self-designed) and instruments to assess body image, quality of life, and health literacy.

Sociodemographic characteristics

Next, a standardized questionnaire was developed based on a review of relevant literature and in line with the study’s objectives and administered to collect information such as age, occupation, residence, gestational age, educational attainment, and body mass index (BMI).

Body image pregnancy scale

The body image pregnancy scale (BIPS), originally developed by Sun Weijia¹⁹, was translated and adapted into Chinese for use among pregnant women. Using exploratory factor analysis (EFA), the adapted scale identified nine dimensions, namely physical strength, appearance attention, facial features, attractiveness to the opposite sex, weight control due to appearance, appearance being prioritized over body function, appearance-related avoidance behavior, and physiological changes during pregnancy), and encompassing 35 items. Confirmatory factor analysis (CFA) demonstrated a strong model fit, with key indices such as RMSEA < 0.08, CFI > 0.90, and TLI > 0.90, indicative of a robust and reliable factorial structure for the Chinese context. The scale employed a 5-point Likert scoring method. The initial section assesses pregnant women’s views on the physical aspects of pregnancy, ranging from 1 (strongly disagree) to 5 (strongly agree), whilst the subsequent section evaluates their satisfaction levels with physical changes, ranging from 1 (very satisfied) to 5 (very dissatisfied). Lastly, the third section examines behavioral evaluations, ranging from 1 (never) to 5 (always). The total score is calculated by summing the score of each item, with higher scores reflecting lower maternal body image levels. The Cronbach’s alpha coefficient of the scale in this study was 0.94.Concurrent validity was established through significant correlations with measures of body image and eating pathology, including the Body Shape Questionnaire (BSQ; r = 0.65–0.80, p < 0.001), Body Image Concern Inventory (BIC; r = 0.60–0.75, p < 0.001), and Eating Disorder Inventory (EDI; r = 0.55–0.70, p < 0.001). In contrast, discriminant validity was supported by weak or non-significant associations with theoretically distinct constructs: psychological distress (Depression, Anxiety, and Stress Scales, DASS; r < 0.30, p < 0.001) and self-esteem (Rosenberg Self-Esteem Scale, RSES; r = 0.20–0.35, p < 0.001).

Quality of life²⁰

The mainland Chinese version of the WHOQOL-BREF consists of 28 items, including 26 standard items from the original WHOQOL-BREF and two additional items unique to the Chinese version. Of the 26 standard items, two focus on overall quality of life and general health, whereas the remaining 24 items are distributed across four domains, namely physical health (7 items), psychological health (6 items), social relationships (3 items), and environment (8 items). The two items specific to the Chinese version are:”Does family friction affect your life?” and “How is your appetite?” These items were included at the end of the questionnaire, reflecting the cultural significance of family dynamics and appetite in Chinese culture as potential indicators of quality of life. Following the recommendations of the developers of the Chinese WHOQOL-BREF, these two culturally specific items were independently analyzed and not included in the domain scores to maintain comparability with the standard WHOQOL-BREF. The answers for each item were recorded on a 5-point Likert scale, with scores ranging between 1–5, and 1 and 5 denoting the minimum and maximum effects, respectively. A higher total of points scored corresponds to a higher QoL in the relevant domain²¹.

Electronic health literacy²²

The electronic health literacy (eHEALS )scale was developed by Norman and Skinner in 2006 and aims to assess electronic health literacy skills, especially the ability to evaluate online information and applications. The eHEALS scale is composed of 8 items, where respondents are asked to rate each item on a five-point Likert scale (strongly disagree, disagree, neither, agree, or strongly agree). Total scores range from 8 to 40, with higher scores indicating higher self-perceived eHL. The score of each item was calculated to obtain the mean score for all Items. The internal consistency of the collected eHEALS data was high, with a Cronbach alpha score of 0.932.

Statistical analysis

This study examined the optimal number of latent profiles representative of patients’ perceptions of each dimension of body image. A range of models with one to four profiles was tested using Mplus 8.3 and robust maximum likelihood estimation for all analyses²³. According to literature guidelines, information criteria (AIC, BIC, and SABIC), wherein lower values indicated a superior model fit, as well as likelihood-based tests (VLMRLRT and BLRT) were used to compare k profile solutions with k-1 profile solutions. A non-significant value (p ≥ 0.05) for the k-profile solution supported the k-1 profile solution.

According to the relative entropy, values ranging from 0.0 to 1.0 indicate greater classification accuracy. Posterior probability analysis was conducted to determine the likelihood of profile inclusion, with values above 0.80 indicating a reliable solution for the profile. Then, a body image classification was established for pregnant women based on their most likely latent class. Several factors associated with body image were identified via multinomial latent variable regressions.

Ethical considerations

All procedures involving human participants in this study adhered to the ethical standards set by the institutional and/or national research committee, in line with the 1964 Helsinki Declaration and its subsequent amendments or comparable ethical standards.The study was approved by the Ethics Committee of the Affiliated Hospital Ethics Committee of Zunyi Medical University. All the participants have filled out an informed consent before participating in the study.