The goal of this cohort study is to investigate the underlying risk factors to develop metabolic syndrome (MetS) during pregnancy, and the associations of MetS and its indicators with birth outcomes in southwest Ethiopia. The study population consists of low-risk pregnant ladies in their first antenatal care visit (ANC), from Jimma Medical center.

The main question[s] it aims to answer are:

i) How do MetS components progress during pregnancy, and what are the underlying risk factors? ii) What is the association between MetS components during early- and late pregnancy and adverse pregnancy outcomes? iii) What is the knowledge, attitude and practices of women toward dietary habits, food taboos, and cultural beliefs during pregnancy?

The study population consists of low-risk pregnant ladies in their first trimester (<15 weeks of pregnancy) in their first antenatal care visit (ANC) who will be followed up until one-month postpartum.

Enrolled women will be assessed four times: at enrolment ≤15 weeks of pregnancy, mid-pregnancy (at 24 weeks), and late pregnancy (at 36 weeks), and within two weeks post-partum for:

1. Sociodemographic data
2. Dietary intake
3. Biochemical analyses
4. Maternal anthropometry:
5. Body composition in a subsample.
6. Knowledge, attitudes and practices of dietary practices during pregnancy
7. Pregnancy and birth outcomes: During the final visit, new born babies will be assessed for Apgar score, weight, length, and head circumference. The mother will be examined for general health and mode of delivery.

Current knowledge about MetS in pregnancy is limited, but it is generally accepted that obesity increases the risk of developing gestational diabetes mellitus (GDM) and preeclampsia (PE). Both of these are associated with an increased risk for developing type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD) in women later in their life. Poor dietary quality, overweight and/or obesity defined by elevated body mass index (BMI ≥25 kg/m2), are the two most common risk factors associated with the development of MetS during pregnancy. MetS is a serious and escalating public health and clinical challenge in the wake of urbanization, surplus energy intake, and sedentary life habits. MetS during pregnancy can result in complications during pregnancy and can affect the birth outcomes resulting in preterm birth (PB) and fetal growth restriction (FGR) escalating the risk for perinatal mortality and morbidity as well as increasing the risk of developing chronic diseases later in life. Identifying early in pregnancy the unfavourable maternal conditions that can predict poor birth outcomes could help their prevention and management and will warrant a close follow-up for these women from long-term complications. Hence the development of context- and population-specific indicators that define the MetS risk in this population is important in the design of interventions that will be targeting the prevention of MetS.

Study objectives: This study aims to investigate the progression of MetS components during pregnancy, and the associations of MetS components with adverse pregnancy outcomes in the mother-infant cohort study southwest Ethiopia.

Primary aim:

To assess the relationship between maternal MetS components and adverse pregnancy outcomes.

Secondary aima:

i) To assess the progression of MetS components during pregnancy, and the underlying risk factors.

ii) To assess the associations between MetS components during early- and late pregnancy and adverse pregnancy outcomes.

iii) To explore knowledge, attitude and practices toward maternal dietary habits, food taboos, and cultural beliefs during pregnancy.

iv) To develop and validate body composition cut-offs for predicting obesity (as a risk factor for MetS) among Ethiopian pregnant women.

Methodology: A prospective maternal-infant cohort study will be conducted at the Jimma Medical Center, southwest Ethiopia.

The study population consists of low-risk pregnant ladies in their first trimester (<15 weeks of pregnancy) in their first antenatal care visit (ANC) who will be followed up until one-month postpartum.

Recruitment will be at one of the following centers including Jimma Medical center, Shenen Gibe General Hospital, Family Guidance Associations (FGA) and two other health centers.

Enrolled women will be assessed four times: at enrolment ≤15 weeks of pregnancy, mid-pregnancy (at 24 weeks), and late pregnancy (at 36 weeks), and within two weeks post-partum.

Statistical analysis will be conducted using STATA. The progression of MetS components during pregnancy will be assessed using the repeated measures ANOVA procedure. Dietary data and physical activities will be tested as the main risk factors. Log binomial regression analyses will be used to examine the risk for each pregnancy outcome with each of the 5 individual components for MetS and as a composite measure (i.e., MetS). The relative risks, adjusted for maternal body mass index (BMI), age, ethnicity, socioeconomic index, physical activity, smoking status, and fetal sex, will be examined.

Additionally, adapted analyses will be used to define the cutoffs of obesity in this population using maternal body composition data (fat mass and fat-free mass)

Inclusion Criteria:

• Apparently healthy women with (or without) at least one of the 5 individual components of MetS will be enrolled in the study from each selected health institution if they meet all the inclusion criteria.

Inclusion criteria for the exposed group include additionally:

1. Abdominal obesity defined as waist circumference ≥ 2 standard deviations (SD) for gestational age in the first half of pregnancy or presentational BMI >30 kg/m2, OR
2. Raised triglycerides (>1.70 mmol/l [>150 mg/dl]), OR
3. Reduced high-density lipoprotein cholesterol (<1.29 mmol/l [<50 mg/dl]), OR
4. Raised blood pressure (BP) (i.e., systolic BP >130 mm Hg or diastolic BP >85 mm Hg), OR
5. Raised plasma glucose (>5.6 mmol/l).

Exclusion Criteria:

• Pregnant women with chronic hypertension that necessitates medication, diabetes (also under medication), or any severe chronic illness will not be eligible to participate in the study. Women who have HIV and who take antiretroviral therapy (ART) are also not eligible because of the side effect of ART. Additionally, non-consenting women, ≤18 years old, women who are planning to move outside the study area within the study timeframe due to job transfer or study leave, or those who are not willing to adhere to the prospective follow up visits will not be included in the study. Women whose ultrasound confirmed, twin pregnancy, congenital anomaly or fetal death in utero will not be included in the study.

Pregnant women in their first trimester, who are residents of Jimma town and nearby kebeles (the smallest administrative division or municipality) will be contacted at the selected health institutions and asked to participate in the study. Eligible women who provide their consent will be recruited. Participants will be selected based on their exposure to one or more components of MetS or not. Sampling will be done consecutively until the required sample is reached.

All the data both from the main and the secondary outcomes will be used in the analyses and shared as necessary.