An interventional study of OMNi-BiOTiC® METAtox in Obesity & Overweight, Gestational Diabetes Mellitus (GDM) and Insulin Resistance, sponsored by Medical University of Vienna. Active, not recruiting at 1 site in Austria. Open to female participants aged 18 Years to 50 Years. Per ClinicalTrials.gov, last updated 2026-11-06.
Sponsored by Medical University of Vienna · Not applicable, Interventional, and Prevention
The goal of this clinical trial is to learn if taking a probiotic supplement during pregnancy improves the body's response to insulin (insulin sensitivity) in pregnant women who were overweight or obese before pregnancy (body mass index ≥25 kg/m2). Reduced insulin sensitivity is common in these women and increases the risk of gestational diabetes mellitus and excessive fetal growth. Growing evidence suggests that the bacteria in the gut (gut microbiome) play a role in regulating blood sugar and insulin action.
The main questions it aims to answer are:
Participants will:
Single-center, open-label, randomized controlled pilot study at the Department of Obstetrics and Gynecology, Division of Obstetrics and Feto-Maternal Medicine, Medical University of Vienna. Participants are randomized 1:1 using minimization method to balance groups according to preconceptional body mass index (25-29.9 vs. ≥30 kg/m2).
Study visits take place at 12+0 to 15+6 weeks of gestation (V1), 24+0 to27+6 (V2) and 35+0 to 37+6 (V3).
V1: anthropometric measurements of the mother including information on weight gain during gestation, fasting blood samples, oral glucose tolerance test (OGTT), continuous glucose monitoring (CGM) for 10 days, dietary and physical activity questionnaires, maternal stool sample, randomization to intervention and control group. Women in the intervention group will take probiotics (OMNi-BiOTiC® METAtox) twice a day starting from V1 until delivery.
V2: anthropometric measurement, fasting blood samples, OGTT, fetal ultrasound, CGM for 10 days, dietary and physical activity questionnaires, maternal stool sample.
V3: anthropometric measurements, fasting blood samples, fetal ultrasound, CGM for 10 days, dietary and physical activity questionnaires, maternal stool sample.
At delivery: recording of obstetric and neonatal outcomes (mode of delivery, birth weight and length with percentiles, APGAR score, shoulder dystocia, neonatal hypoglycemia, admission to neonatal intensive care unit, umbilical cord sampling (blood glucose, insulin, c-peptide, pH, base excess), collection of the first neonatal stool (meconium).
As a pilot study, all analyses are exploratory and intended to generate effect estimates and hypotheses for future trials.
11,522 studies on the registry are indexed under Obesity; 2,033 are open to participants now.
This study's enrollment of 40 is below the median of 67 across 9,006 interventional studies indexed under Obesity.
Browse Obesity studies →Medical University of Vienna is the lead sponsor of 1,109 studies on the registry; 184 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Women with a preconceptional BMI ≥25 kg/m2 taking one sachet of OMNi-BiOTiC® METAtox twice a day starting from randomization (12+0 to 15+6 weeks of gestation) until delivery.
Dietary Supplement: OMNi-BiOTiC® METAtox
Women with a preconceptional BMI ≥25 kg/m2 receiving standard prenatal care without probiotic supplementation.
Multispecies probiotic containing 9 specially selected bacterial strains (Lactobacillus casei W56, Lactobacillus acidophilus 5 W37, Lactobacillus brevis W63, Lactococcus lactis W58, Lactococcus lactis W19, Bifidobacterium lactis W52, Lactobacillus salivarius W24, Bifidobacterium lactis W51, Bifidobacterium bifidum W23) at a concentration of 7.5 \* 109 cfu (colony forming units) per portion (= 3 g). The intervention group will take one sachet of OMNi-BiOTiC® METAtox twice daily (in the morning and in the evening) before a meal. The dosing interval should be approximately 12 hours, and the intake is to be carried out continuously until delivery. The contents of one sachet must be stirred into a minimum of 100 ml of water. After an activation time of at least 1 minute, the suspension must be stirred again and then consumed.
Insulin sensitivity assessed by the PREDIM index
Insulin sensitivity will be assessed by the Predicted M index (PREDIM), derived from a 2-h 75g oral glucose tolerance test and compared between groups.
Time frame: 12+0 to 15+6 (V1) and 24+0 to 27+6 (V2) weeks of gestation
Further insulin sensitivity and insulin resistance indices
Insulin sensitivity and insulin resistance indices (OGIS, Matsuda Index, HOMA-IR, QUICKI) derived from a 2-h 75g oral glucose tolerance test and compared between groups.
Time frame: 12+0 to 15+6 (V1) and 24+0 to 27+6 (V2) weeks of gestation
Insulin secretion and beta-cell function indices
Insulin secretion and beta-cell function indices (insulinogenic index, oral disposition index) derived from a 2-h 75g oral glucose tolerance test and compared between groups.
Time frame: 12+0 to 15+6 (V1) and 24+0 to 27+6 (V2) weeks of gestation
Glycemic profile assessed by continuous glucose monitoring
Mean glucose and percentage of time in range (63-140mg/dL), above, range and below range over 10 days continuous glucose monitoring
Time frame: 12+0 to 15+6 (V1), 24+0 to 27+6 (V2) and 35+0 to 37+6 (V3) weeks of gestation
Fetal growth parameters assessed by ultrasound
Head circumference, biparietal diameter, abdominal circumference, abdominal fat thickness, femur length, and estimated fetal weight, expressed as absolute values and gestational age-specific percentiles.
Time frame: 24+0 to 27+6 (V2) and 35+0 to 37+6 (V3) weeks of gestation
Umbilical cord blood glucose
Glucose concentration (mg/dL) in umbilical cord blood.
Time frame: At delivery
Umbilical cord blood insulin
Insulin concentration (µU/ml) in umbilical cord blood.
Time frame: At delivery.
Umbilical cord blood C-peptide
C-peptide concentration (ng/ml) in umbilical cord blood.
Time frame: At delivery.
Umbilical cord blood pH
Arterial umbilical cord blood pH.
Time frame: At delivery.
Umbilical cord blood base excess
Arterial umbilical cord blood base excess (mmol/L).
Time frame: At delivery.
Birth weigth percentile and proportion of large- and small-for-gestational-age newborns
Sex- and gestational age-adjusted birth weight percentile, large for gestational age defined as \>90th percentile, small for gestational age as \<10th percentile
Time frame: At delivery
Obstetric and neonatal outcomes
Mode of delivery, APGAR score, shoulder dystocia, neonatal hypoglycemia, admission to neonatal intensive care unit
Time frame: From delivery up to 48 hours postpartum
Maternal and neonatal gut microbiome composition
Bacterial and fungal composition of maternal stool and neonatal meconiumassessed by 16S rRNA and ITS amplicon sequencing
Time frame: Maternal: 12+0 to 15+6 (V1), 24+0 to 27+6 (V2) and 35+0 to 37+6 (V3) weeks of gestation Neonatal: first stool after birth
Maternal fasting triglycerides
Fasting serum triglyceride concentration (mg/dL).
Time frame: 12+0 to 15+6 (V1), 24+0 to 27+6 (V2) and 35+0 to 37+6 (V3) weeks of gestation
Maternal fasting total cholesterol
Fasting serum total cholesterol concentration (mg/dL).
Time frame: 12+0 to 15+6 (V1), 24+0 to 27+6 (V2) and 35+0 to 37+6 (V3) weeks of gestation
Maternal fasting LDL cholesterol
Fasting serum LDL cholesterol concentration (mg/dL).
Time frame: 12+0 to 15+6 (V1), 24+0 to 27+6 (V2) and 35+0 to 37+6 (V3) weeks of gestation
Maternal fasting HDL cholesterol
Fasting serum HDL cholesterol concentration (mg/dL).
Time frame: 12+0 to 15+6 (V1), 24+0 to 27+6 (V2) and 35+0 to 37+6 (V3) weeks of gestation
Maternal HbA1c
Glycated haemoglobin (HbA1c, %)
Time frame: 12+0 to 15+6 (V1), 24+0 to 27+6 (V2) and 35+0 to 37+6 (V3) weeks of gestation
Dietary quality assessed by a validated food frequency questionnaire
Diet quality assessed by a food frequency questionnaire (FFQ, Robert Koch Institute) and summarized as a modified Alternate Healthy Eating Index 2010 (AHEI-2010) adapted for pregnancy. Score range 0 to maximum, higher scores indicate better diet quality.
Time frame: 12+0 to 15+6 (V1), 24+0 to 27+6 (V2) and 35+0 to 37+6 (V3) weeks of gestation
Physical activity assessed by the International Physical Activity Questionnaire (IPAQ)
Total physical activity assessed by the IPAQ long form, expressed as metabolic equivalent of task (MET) minutes per week. Higher values indicate more physical activity.
Time frame: 12+0 to 15+6 (V1), 24+0 to 27+6 (V2) and 35+0 to 37+6 (V3) weeks of gestation
Plan to share: No
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Ran from Oct 2024 to primary completion in Oct 2026, 24 months.
Of 3,680 non-industry interventional studies with no phase under Obesity, half reached primary completion within 23 months of starting (the median), counting those still running; a quarter within 10 and three quarters within 43. This study's 24 months is close to that.
Counting every sponsor, half of 3,843 studies reached it within 22 months; a quarter within 10 and three quarters within 42.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is active, not recruiting, as verified in Nov 2026. You cannot join it, but the record below documents what was studied.
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