Fiber Nutritional Supplement for Management of Constipation During Pregnancy

Inclusion Criteria: 1. Pregnant women aged 21 years-old or above at recruitment 2. Gestational age of 13-27 weeks at recruitment 3. Singleton pregnancy at recruitment 4. Suffering from functional constipation according to the Cullen 2007 criteria which must include ALL the following and the criteria must be fulfilled for at least two weeks with symptom onset during pregnancy: 1. Low frequency of stool (\<3/week) 2. Hard stools 3. Difficulty on evacuation 5. Able to understand and to sign a written Informed Consent Form (ICF) prior to study enrolment. 6. Willing and able to comply with the requirements for participation in this study 7. Willing and able to refrain from consuming other supplements containing fiber, prebiotics, or probiotics other than the Fiber Nutritional Supplement (Materna® Opti-fiber) over the intervention period 8. Able to respond to questionnaires in English Exclusion Criteria: 1. Treated for constipation less than one week before the start of the study 2. Use of prebiotics or probiotics containing supplements two weeks prior to the study start 3. Major complications during pregnancy e.g., pre-eclampsia, gestational diabetes requiring insulin intervention, severe intra-uterine growth restriction (IUGR), fetal anomalies that in the opinion of the investigator may interfere with the pregnancy and participation in the clinical trial 4. Pre-existing medical conditions e.g., hypertension, diabetes mellitus, thyroid diseases, autoimmune diseases such as Systemic Lupus Erythematosus, antiphospholipid syndrome and other major chronic illness that in the opinion of the investigator may interfere with the pregnancy and participation in the clinical trial 5. Not willing and/or not able to comply with the study procedures and requirements 6. Known serious food allergy 7. Known or suspected history of allergy or intolerance to the investigational product (IP) 8. Active participation in another clinical trial or on-going observational study 9. Family or hierarchical relationships with the research team members