Introduction

Pregnancy is an important period in human’s life and plays an essential role in materno-fetal health and later, on the wellbeing of the children¹. Moreover, maternal nutrition during pregnancy is a major determinant for pregnancy outcome and, offspring’s health outcomes in later life². Moderate increases in energy, macronutrients, and most of the micronutrient intakes in the second and third pregnancy trimesters are needed for healthy pregnancy outcomes³. On contrary, excessive weight gain due to unhealthy dietary pattern during pregnancy increases the risk of complications during pregnancy and delivery, such as gestational diabetes, pre-eclampsia, stillbirth  and caesarean delivery in addition to postpartum retained maternal weight gain and childhood obesity⁴. Furthermore, behavioral interventions such as weight awareness and dietary pattern improvement may reduce the risks of pregnancy complications¹.

The study of dietary patterns among pregnant women when compared to single nutrients or foods offers a broader view of food and nutrient consumption. These patterns reflect the overall dietary behavior of the mothers thus enhancing a better understanding of diet-pregnancy interaction⁵.

Various approaches to study the overall diet can be distinguished. Many dietary patterns were reported throughout literature; nevertheless, they vary according to geographical localization. In Iran, most pregnant women followed a traditional Iranian dietary pattern according to a study by Esmaillzadeh et al (2008)⁶. Paknahad et al (2019) identified three major dietary patterns among pregnant women: ‘high carbohydrate lower fat’, ‘High Carbohydrate higher fat’ and ‘High Fiber’⁷. On the other hand, in Denmark, other three considerable dietary patterns were recognized: “the Western diet”; being the most commonly pattern followed by pregnant women, the ‘Health Conscious diet’, while the ‘Intermediate diet’ incorporated foods of both patterns⁸. However, in Sweden, the ‘Prudent’ pattern, i.e. healthy diet, was reported to be the most popular one among pregnant women pursued closely by the ‘Western diet’⁵. The western dietary pattern was distinguished by high intakes of red and processed meat, high-fat dairy, whilst the prudent and health conscious dietary patterns were characterized by a remarkable consumption of fruits and vegetables^{5, 8}.

Many factors influence dietary patterns of pregnant women including educational levels, financial status, and age⁹. Higher educational level may positively affect the dietary pattern among pregnant women, as shown by many studies that correlated a higher adherence rate to healthy dietary style and the higher educational level^9,10.

In Jordan, pregnant women were found to be above the median levels of consumption of energy, fat, protein and vitamin C, near the median in their carbohydrate, calcium and vitamin A intakes, and below the median consumptions of folate, iron and zinc as compared to the countries included in the study¹¹. However, studies related to the dietary patterns adopted by Jordanian pregnant women are rare, if any. Therefore, this study aimed, mainly, to identify the dietary patterns followed by Jordanian pregnant women mainly during the second and third trimesters and during the whole course of pregnancy. Additionally, the study evaluated the possible association between the educational level and the dietary patterns that the women followed during their pregnancy.

Methods

Study Design and Participant

This cross-sectional, observational study aimed to determine the dietary patterns followed by Jordanian women during pregnancy. The methodology of the study was described in detail by Tayyem et al. (2014)¹². The study was carried out in Jordan University Hospital from March 2017 to December 2018. Three hundred and ten pregnant Jordanian women were recruited during their antenatal visits at the maternity clinics. Out of the 310 women, 286 were eligible and agreed to be enrolled in the study and complete all the required information. Participants were classified based on their gestational age; 50 pregnant women in the first trimester (9 to 13 weeks of gestation), 96 pregnant women in the second trimester (14 to 26 weeks of gestation), and 137 pregnant women in the third trimester (27 to 36 weeks of gestation). Gestational age was calculated based on the time of last menstruation and ultrasound fetal measurements by her physician¹³.

Eligibility criteria entitled healthy Jordanian pregnant women and aged 18 years or older with singleton pregnancy. However, many women were excluded if they suffer from complicated pregnancies by gestational preeclampsia, diabetes, hyperemesis gravidarum, inflammatory and autoimmune disorders or any other chronic diseases that require special diets such as renal disease, liver disease, and diabetes.

The study was conducted according to the guidelines in the Declaration of Helsinki. All participants were asked to sign a written consent form before the enrollment in the study.

Data Collection

Women who were eligible for the study were interviewed to complete 3 questionnaires: sociodemographic questionnaire, food frequency questionnaire (FFQ), and pregnancy physical activity questionnaire (PPAQ).

Socio-Demographic Data

Data about pre-pregnancy bodyweight, maternal age, family income, smoking, and education level were recorded by the dietitian using structured questionnaire.

Dietary Intake Assessment

A validated and reliable Arabic quantitative FFQ was used to assess the intake from all the food groups¹².  In-person interview was accomplished by a trained dietitian to complete the FFQ. The dietitian asked participants how often, on average, they had consumed each food item over the past month. Portion size of each food item was estimated using food models and measuring cups and spoons. In addition, information about food preparation and cooking techniques and the use of dietary supplements were collected. Afterwards, the acquired data from the FFQ were calculated using ESHA Food-Processor software for nutrients’ analysis¹⁴.

Physical Activity Data

PPAQ has been developed to evaluate the duration, intensity, and frequency of physical activity performed by pregnant women. This questionnaire has been validated and is considered a reliable tool for the evaluation of physical activity practiced by women during pregnancy¹⁵. All participants completed the PPAQ during a face-to-face interview. Physical activity level was estimated to adjust for its effect on the association between educational level and dietary patterns followed by the pregnant women.

Anthropometric Assessment

Weight and height of pregnant women were determined using the standardized methods and tools (Health-O-meter Professional). Pre-pregnancy bodyweight was recorded from the medical files of the pregnant women and for some of them it was self-reported. Pre-pregnancy body mass index (BMI) was calculated and categorized according to WHO guidelines¹⁶. Pre-pregnancy body weight was measured for the purpose of controlling their effect on the association between educational level and dietary patterns during the pregnancy time.

Statistical Analysis

The data was analyzed using the Statistical Package for the Social Sciences version 22. Dietary patterns were derived using Principal Component Analysis (PCA), form factor analysis. The food items in the FFQ were divided into 23 food groups and items, based on their similarity of nutrient content and culinary usage. These food groups included: fruit juices, sugary drinks, coffee, sweetened tea, banana, orange, apple, vegetables, starchy vegetables, fried potato, olive oil and pickled olives, grains and cereals, dairy products, processed meat, red meats, white meats, traditional and western fast food, eggs, sweets and desserts, falafel, cheese, vegetable oils, and animal fats.

Kaiser-Meyer-Olkin (KMO) test and Bartlett’s test of sphericity were performed to assess the appropriateness for using factor analysis for this exercise. The Kaiser-Meyer-Olkin value of >0.600 and Bartlett’s test of sphericity <0.001 were selected to evaluate the inter-correlation of factors and sampling adequacy. Factors were taken based on an eigenvalue of >1.25 for screen plot. Varimax rotation was performed to review the relationships between factors and variables. The absolute factor loadings >0.30 were considered for the food groups/items to be considered significant contributor to the pattern.

A multinomial logistic regression was used to estimate the effect of education level on dietary intake, in which 4 quartiles were computed for each dietary pattern using the adherence scores, and the lowest quartile was set as the reference value. Two models of adjustment were used to calculate odds ratio OR and CI. The first model was adjusted for age (continuous) and BMI (continuous), while the second one was adjusted for age (continuous) and BMI (continuous), physical activity level (continuous), and number of pregnancy (categorical)¹⁷. The educational level was divided into 2 categories, the higher level of education was set as the reference category. Diploma and above were considered as higher level of education.

Results                       

The Characteristics of the Participants

As described in a previous study by Tayyem et al. (2019)¹¹ on the same sample, the mean gestational ages of the women at enrollment was 9.0 ± 3.1, 20.0 ± 3.7, and 30.0 ± 3.2 weeks in the first, second and third trimesters of pregnancy, respectively. The lowest body weight and BMI at enrollment was documented in pregnant women at the first trimester as compared with women in the second and third trimesters. Additionally, a large percentage of participants 68%, 79.2%, and 63.6% had college degree and above in the first, second and third trimesters of pregnancy, respectively. Regarding the physical activity, Tayyem et al. (2019)¹¹ showed that the time spent (minutes of moderate and vigorous activity/ day) in physical activity was 58.9 ± 10.8, 67.7 ± 8.5, 56.3 ± 4.7 in the first, second and third trimesters of pregnancy, respectively, for the study sample.

Dietary Patterns During the Whole Pregnancy Period

Three factors were identified to describe the dietary patterns of the Jordanian pregnant women as shown in table 1. Collectively these factors explained 32.3% of the variability within the sample with KMO of 0.730. Food items with loadings of >0.3 on a factor were considered to have a strong association with that factor. The three factors were named according to the food item loadings as ‘High-Fat, High-Sugar’, ‘Fruit and Vegetables’, and ‘High Protein’. The ‘ High-Fat, High-Sugar’ dietary pattern was loaded by fried potato, starchy vegetables, Falafel, olive oil, sweetened tea, sugar and sweets, processed meats and vegetable oils, while ‘Fruit and Vegetables’ pattern consisted of a plenty of bananas, apples, oranges, vegetables, fruit juices, and sugary drinks. On the other hand, ‘High Protein’ pattern was marked by red and white meats, dairy products, cheese, egg, grains and cereals and vegetable oils.

Table 1: Factor Loading Matrix for the Identified Dietary Patterns among the Jordanian Pregnant Women during their Second, Third and Whole Pregnancy Period. Click here to view Table

Dietary Patterns During the Second Trimester of Pregnancy

In this trimester four factors were recognized to describe the dietary patterns of the Jordanian pregnant women as depicted in table 1. These four factors explained 40.1% of the variability within the enrolled pregnant women with KMO of 0.597. The four factors were named according to the food item loadings as ‘Fast Food’, ‘Traditional Jordanian’ ‘Fruit and Vegetables’, and ‘High-Fat, High Sugar’. White and red meat, cheese, dairy products, banana, olive oil, egg, and vegetables showed high loadings in ‘Traditional Jordanian’ pattern. Whilst fried potato, sweetened tea, starchy vegetables, olive oil, vegetable oils, falafel and sugar and sweets were heavily loaded in ‘High Fat, High Sugar’ pattern.

Dietary Patterns During the Third Trimester of Pregnancy

Four factors were detected to define the dietary patterns of the Jordanian pregnant women in their third trimester as shown in table 1. These four factors explained 41.13% of the variability within the sample with KMO of 0.738. As shown in table 1, food items with loadings of >0.3 on a factor were considered to have a strong association with that factor and represented in bold. The four factors were named according to the food item loadings as ‘High-Fat, High-Sugar’, ‘Fruit and Vegetables’, ‘High-Protein’ and ‘Healthy’. These three dietary patterns: ‘High-Fat, High-Sugar’, ‘Fruit and Vegetables’, ‘and ‘Healthy’ were similar the patterns of the second trimester. However, ‘High-Protein, High Sugar’ dietary pattern was loaded with fruit juices, sugary drinks, red meats, white meats, dairy products, and sugar and sweets.

Association Between Educational Level and Dietary Patterns During Pregnancy

The results which are presented in table 2 show that adherence of pregnant women to “Fruits and Vegetables” pattern or “Healthy” pattern was significant in educated women. About 50-60% of the highly educated pregnant women showed adherence to ‘Fruit and Vegetable’ and/or ‘Healthy’ patterns in the third trimester (the significant odds range was from 0.39 to 0.51). No dietary pattern was spotted to relate the educational level to the whole pregnancy and the second trimester (data not shown).

Table 2: Association Between Educational Levels and Dietary Patterns in the Third Trimester

^#OR and CI: odd ratio and confidence interval

^* Adjusted for age and BMI

^**Adjusted for age, BMI, physical activity and number of regnancies

Discussion

This study aimed to identify the major dietary patterns consumed by Jordanian pregnant women during the second and third trimesters as well as the whole course of pregnancy and their association with educational level. Dietary patterns are expected to offer a better evaluation of dietary intake as explained by Borge et al (2017)¹⁸. Our findings revealed that different dietary patterns were adopted by Jordanian pregnant women in the different trimesters, where the main shared dietary patterns in the identified factors were ‘Fruit and Vegetables’ and ‘High-Fat, High-Sugar’ dietary patterns. In addition, a third dietary pattern named as ‘High-Protein’ pattern was identified all over pregnancy. The presence of three different dietary patterns could be attributed to the differences in attitudes, believes and backgrounds among pregnant women. Moreover, dietary modification is recommended for the management of nausea and vomiting during pregnancy with reduction in fatty foods and fresh vegetables that cause delayed gastric emptying¹⁹. When we compare the dietary patterns of pregnant women during the second and third trimesters, further distinct differences were revealed which could be attributed to maternal gastrointestinal symptoms such as gastroesophageal reflux and constipation that are managed initially by lifestyle and dietary modification²⁰. These differences can be summarized by the presence of ‘Traditional Jordanian’, among women in the second trimester, a pattern that reflects the usual items consumed by typical Jordanians including eggs, olive oil, white and red meats, cheese, dairy products, banana and vegetables^21,22. On the other hand, ‘Healthy’ pattern of consumption was apparent during the third trimester which could be explained by the mechanical pressure of the gravid uterus in addition to the gastroesophageal reflux, therefore women avoid certain foods that may aggravate their discomfort.

In line with our findings, many studies showed different dietary patterns among pregnant women^{8, 23-26}. Arkkola et al (2008) identified seven factors: ‘Healthy’, ‘Fast Food’, ‘Traditional bread’, ‘Traditional meat’, ‘Coffee’, ‘Alcohol and ‘Butter’ patterns²⁴. The authors attributed the identification of seven dietary patterns compared to an earlier cohort study²³ that showed only two important dietary patterns, ‘healthy’ and ‘traditional’, to the fact that people’s eating habits vary very rapidly at present than ever before. This is probably due to the availability of varied choices of food products in the markets, in addition to the different eating styles and habits especially during pregnancy. Another study by Knudsen recognized two major dietary patterns in pregnant women in Denmark⁸. The first pattern was characterized by red and processed meat, ‘high-fat dairy’, while vegetables, fruits, poultry, and fish marked the second pattern. Furthermore, women were classified into three classes according to their diet: the ‘Western diet’ consumers had high consumption of foods of the first dietary pattern, the second class favored foods of the second pattern and was classified as the ‘Health Conscious’, and the third one had eaten foods of both patterns and was classified as the ‘Intermediate’⁸. Another study conducted on Brazilian pregnant women showed that four dietary patterns were identified among those women, “traditional Brazilian”, “snacks”, “coffee” and “healthy” patterns, in which greater commitment to “healthy” and “traditional Brazilian” patterns were inversely associated with weight gain²⁶. The significant disparities in dietary patterns among pregnant women could be due to pregnancy-related aversion and craving of certain food items that could drive the intake toward a specific and distinct pattern of consumption. Furthermore, food choices may be derived by the levels of health awareness and perception.

Regarding the effect of educational level on the adherence to specific dietary pattern, our results showed that about 50-60% of the highly educated pregnant women adhered to ‘Fruit and Vegetable’ dietary pattern and ‘Healthy’ pattern during their third trimester. Yet, the whole pregnancy and the second trimester did not show any association with any dietary pattern. Our findings correlated with many studies which revealed that higher education was associated with more adherences to healthy dietary patterns^{24, 27-28}.  Olmedo-Requena et al (2014) showed that Spanish pregnant women with higher educational level and higher social class were more committed to the Mediterranean diet (P<0.001)²⁸. Another study reported that the consumption of a ‘Health Conscious’ diet was positively associated with increasing education and age⁹. Studies, also, reported the association between low adherence to a ‘Healthy’ diet and Mediterranean diet and lower level of education (primary, secondary)^27,29.  Additionally, it has been found that maternal total vegetable consumption was positively associated with maternal education, household income, and breastfeeding duration¹⁰ as indicated in our study findings. Englund-Ögge et al (2014) documented that the highest scores for the Western pattern were found among women who were younger, smokers, overweight, and had less years of formal education⁵. All these studies confirm that higher education of the pregnant women could be associated with better understanding to the benefits of healthy diet for the fetus and for the mother now and in later life. Additionally, sometimes better education may provide more financial abilities to purchase more healthy foods and have a variety of choices. In a study in Bangladesh by Shamim¹¹, women who completed secondary or higher level of education were 2.5 times more likely to have diet diversity score than the functionally illiterate 2.58 (1.27-5.24, P < .001).

The main limitation of this study was the possible errors inherited with women, which was reflected by an adjusted OR (95% CI) of FFQ technique related to possible overestimating or underestimating of nutrients intake as well as recall bias. However, to reduce the recall and estimation errors, a validate FFQ containing foods culturally adapted to Jordanian pregnant women along with food models and measuring tools for accurate estimation of portion sizes were used. Further, a trained nutritionist conducted in-person interviews to collect all the required data and to minimize missing data. Another limitation of the present study could be our inability to identify the dietary patterns during the first trimester due to its low KMO values (less than 0.4), however, this is an expected result because most of the pregnant women do not have a specified dietary pattern due to vomiting, morning sickness, anorexia and nausea and other pregnancy symptoms and signs³⁰. Also, the small sample size in this trimester could be another factor.  We acknowledge that pregnancy and neonatal outcomes were not studied.

In conclusion, food choices and patterns of consumption of pregnant women could be derived by their level of education and health perception particularly in the third trimester. Different dietary patterns have been itemized during the second and third trimesters, in which ‘Fruit and Vegetable’ as well as ‘Healthy’ patterns were the main patterns followed by pregnant women with higher educational levels.

Authority

RT and FA participated in conception and design of the study. RT, SA, SH and DA performed statistical analysis and interpreted the study results. RT, SH and LD drafted the manuscript. All authors drafted the manuscript and approved it.

Ethical Approval

The study was conducted in accordance with the ethical standards of the responsible committee on human experimentation and with the Helsinki declaration of 1975. The proposal was approved by the Hashemite University Ethics Committee (1601100/10/13/16/ام) and Institutional Review Board of Jordan University Hospital (10/2016/3341).

Acknowledgments

The authors would like to thank the Hashemite University for funding the research project (Grant number 16/13/10/1601100).

Consent for Publication

The Authors agree to deliver to the responsible Editor(s) on a date to be agreed upon the manuscript created according to the Instructions for Authors.

Conflict of Interest

The authors declare that they have no conflict of interests.

Funding Source

This project was funded by the Hashemite University (Grant number 16/13/10/1601100).

Availability of Data and Materials Statement

The raw data required to reproduce these findings are available on request from the corresponding author.

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