The Microbiome in (Non-) Obese Pregnancy and Pregnancy Outcomes

Study Overview
=================
Brief Summary
-----------------
This research aims to elucidate an underlying mechanism of maternal obesity induced pregnancy and longterm health complications for mothers and their offspring.

Detailed Description
-----------------
With the increasing global prevalence of obesity, pregnancy problems related to maternal obesity are increasingly occurring. Microbial gut symbiosis plays an important role in health, with dysbiosis being associated with diseases such as obesity. Of interest are pregnancy, dietary patterns and pre- or probiotics that affect the composition of the gut microbiome. The microbiome itself can influence many physiological processes, such as immune responses (production of microbial products) and the nutrient-dependent one-carbon metabolism. It is hypothesized that gut dysbiosis, due to maternal obesity, during pregnancy can be considered an endogenous chronic stressor causing impaired immune response and carbon metabolism. Both processes result in excessive oxidative stress, detrimental to cell replication, differentiation and epigenetic programming of maternal and infant tissues. Together, these biological disturbances contribute to placental and vascular dysfunction, leading to an increased risk of preeclampsia or gestational diabetes mellitus. Vertical (during pregnancy) and horizontal (during delivery) transmission of gut dysbiosis from mother to newborn and epigenetic placental and foetal changes may ultimately lead to macrosomia and obesity in children. Therefore, the differences between the gut and vaginal microbiome, maternal and fetal immune responses and one-carbon metabolism in obese versus normal-weight pregnant women will be analysed.

Official Title
-----------------
The PROMOTE Study, a Pilot: The Characterization of the Microbiome in Pregnancy and Prediction of Pregnancy Outcomes

Conditions
-----------------
Obesity, Maternal, Pregnancy Complications, Gut Microbiota

Intervention / Treatment
-----------------
* Other: Blood withdrawal


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Participation in Predict study Preconceptional women who wish to become pregnant or pregnancy <13 weeks of gestational age. BMI > 30 kg/m2 or 18-25 kg/m2 Understanding of Dutch in speaking and reading Willingness to give written informed consent Exclusion Criteria: Age < 18 years and > 45 years. ≥13 weeks of gestational age Multiple pregnancy Smoking Gastro-intestinal diseases, heart diseases, liver, pancreas and kidney diseases. Use of antibiotics < 2 weeks before sampling Pre-existent diabetes mellitus

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
-----------------
Female

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 110 women<br>60 women with a BMI between 18,5-25 kg/m2, of which 10 preconceptional 60 women with a BMI > 30 kg/m2, of which 10 preconceptional | Other: Blood withdrawal<br>* venous punction with blood withdrawal Vaginal and rectal swab, done by patient itself<br>* Other names: Vaginal/rectal swabs;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Gut and vaginal microbiota | Composition of gut and vaginal microbiota derived by swab sampling, bacteriome profiles will be assessed by 16S ribosomal ribonucleic acid (16SrRNA) gene amplification sequencing (V6-V8). Sequences will be assigned to operational taxonomic units (OTUs). | Preconceptional (up to 1 year before pregnancy) | 
| Gut and vaginal microbiota | Composition of gut and vaginal microbiota derived by swab sampling, bacteriome profiles will be assessed by 16SrRNA gene amplification sequencing (V6-V8). Sequences will be assigned to OTUs. | First trimester (between 7-12 weeks gestational age) | 
| Gut and vaginal microbiota | Composition of gut and vaginal microbiota derived by swab sampling, bacteriome profiles will be assessed by 16SrRNA gene amplification sequencing (V6-V8). Sequences will be assigned to OTUs. | Second trimester (between 22-25 weeks gestational age) | 
| Gut and vaginal microbiota | Composition of gut and vaginal microbiota derived by swab sampling, bacteriome profiles will be assessed by 16SrRNA gene amplification sequencing (V6-V8). Sequences will be assigned to OTUs. | Third trimester (between 30-32 weeks gestational age) | 
| Gut and vaginal microbiota | Composition of gut and vaginal microbiota derived by swab sampling, bacteriome profiles will be assessed by 16SrRNA gene amplification sequencing (V6-V8). Sequences will be assigned to OTUs. | Antepartum (during delivery) | 
| Gut and vaginal microbiota | Composition of gut and vaginal microbiota derived by swab sampling, bacteriome profiles will be assessed by 16SrRNA gene amplification sequencing (V6-V8). Sequences will be assigned to OTUs. | Postpartum (6-8 weeks post delivery) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Gut virome | Composition of gut virome, obtained by a rectal swab | Preconceptional (up to 1 year before pregnancy) | 
| Gut virome | Composition of gut virome, obtained by a rectal swab | First trimester (between 7-12 weeks gestational age) | 
| Gut virome | Composition of gut virome, obtained by a rectal swab | Second trimester (between 22-24 weeks gestational age) | 
| Gut virome | Composition of gut virome, obtained by a rectal swab | Third trimester (between 30-32 weeks gestational age) | 
| Gut virome | Composition of gut virome, obtained by a rectal swab | Antepartum (during delivery) | 
| Gut virome | Composition of gut virome, obtained by a rectal swab | Postpartum (6-8 weeks post delivery) | 
| Maternal immune response | Responses of maternal immune system advanced oxidation protein products (AOPP)) measured in chloramine units per gram of protein (micromol/g) obtained by blood withdrawal and measured in the lab. | Preconceptional (up to 1 year before pregnancy) | 
| Maternal immune response | Responses of maternal immune system advanced oxidation protein products (AOPP)) measured in chloramine units per gram of protein (micromol/g) obtained by blood withdrawal and measured in the lab. | First trimester (between 7-12 weeks gestational age) | 
| Maternal immune response | Responses of maternal immune system advanced oxidation protein products (AOPP)) measured in chloramine units per gram of protein (micromol/g) obtained by blood withdrawal and measured in the lab. | Second trimester (between 22-24 weeks gestational age) | 
| Maternal immune response | Responses of maternal immune system advanced oxidation protein products (AOPP)) measured in chloramine units per gram of protein (micromol/g) obtained by blood withdrawal and measured in the lab. | Third trimester (between 30-32 weeks gestational age) | 
| Maternal immune response | Responses of maternal immune system advanced oxidation protein products (AOPP)) measured in chloramine units per gram of protein (micromol/g) obtained by blood withdrawal and measured in the lab. | Antepartum (during delivery) | 
| Maternal immune response | Responses of maternal immune system advanced oxidation protein products (AOPP)) measured in chloramine units per gram of protein (micromol/g) obtained by blood withdrawal and measured in the lab. | Postpartum (6-8 weeks post delivery) | 
| Maternal immune response | Tumor necrosis factor-alpha (TNF-alpha) measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | Preconceptional (up to 1 year before pregnancy) | 
| Maternal immune response | Tumor necrosis factor-alpha (TNF-alpha) measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | First trimester (between 7-12 weeks gestational age) | 
| Maternal immune response | Tumor necrosis factor-alpha (TNF-alpha) measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | Second trimester (between 22-24 weeks gestational age) | 
| Maternal immune response | Tumor necrosis factor-alpha (TNF-alpha) measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | Third trimester (between 30-32 weeks gestational age) | 
| Maternal immune response | Tumor necrosis factor-alpha (TNF-alpha) measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | Antepartum (during delivery) | 
| Maternal immune response | Tumor necrosis factor-alpha (TNF-alpha) measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | Postpartum (6-8 weeks post delivery) | 
| Maternal immune response | Interleukin-6 (IL-6), measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | Preconceptional (up to 1 year before pregnancy) | 
| Maternal immune response | Interleukin-6 (IL-6), measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | First trimester (between 7-12 weeks gestational age) | 
| Maternal immune response | Interleukin-6 (IL-6), measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | Second trimester (between 22-24 weeks gestational age) | 
| Maternal immune response | Interleukin-6 (IL-6), measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | Third trimester (between 30-32 weeks gestational age) | 
| Maternal immune response | Interleukin-6 (IL-6), measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | Antepartum (during delivery) | 
| Maternal immune response | Interleukin-6 (IL-6), measured in picograms per milliliter, obtained by blood withdrawal and measured in the lab. | Postpartum (6-8 weeks post delivery) | 
| Maternal immune response | high sensitive C-reactive protein(hsCRP), measured in mg/L, obtained by blood withdrawal and measured in the lab. | Preconceptional (up to 1 year before pregnancy) | 
| Maternal immune response | high sensitive C-reactive protein(hsCRP), measured in mg/L, obtained by blood withdrawal and measured in the lab. | First trimester (between 7-12 weeks gestational age) | 
| Maternal immune response | high sensitive C-reactive protein(hsCRP), measured in mg/L, obtained by blood withdrawal and measured in the lab. | Second trimester (between 22-24 weeks gestational age) | 
| Maternal immune response | high sensitive C-reactive protein(hsCRP), measured in mg/L, obtained by blood withdrawal and measured in the lab. | Third trimester (between 30-32 weeks gestational age) | 
| Maternal immune response | high sensitive C-reactive protein(hsCRP), measured in mg/L, obtained by blood withdrawal and measured in the lab. | Antepartum (during delivery) | 
| Maternal immune response | high sensitive C-reactive protein(hsCRP), measured in mg/L, obtained by blood withdrawal and measured in the lab. | Postpartum (6-8 weeks post delivery) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; folate, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Preconceptional (up to 1 year before pregnancy) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; folate, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | First trimester (between 7-12 weeks gestational age) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; folate, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Second trimester (between 22-24 weeks gestational age) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; folate, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Third trimester (between 30-32 weeks gestational age) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; folate, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Antepartum (during delivery) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; folate, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Postpartum (6-8 weeks post delivery) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; Homocysteine, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Preconceptional (up to 1 year before pregnancy) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; Homocysteine, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | First trimester (between 7-12 weeks gestational age) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; Homocysteine, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Second trimester (between 22-24 weeks gestational age) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; Homocysteine, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Third trimester (between 30-32 weeks gestational age) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; Homocysteine, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Antepartum (during delivery) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; Homocysteine, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Postpartum (6-8 weeks post delivery) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; B-vitamin 12, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Preconceptional (up to 1 year before pregnancy) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; B-vitamin 12, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | First trimester (between 7-12 weeks gestational age) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; B-vitamin 12, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Second trimester (between 22-24 weeks gestational age) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; B-vitamin 12, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Third trimester (between 30-32 weeks gestational age) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; B-vitamin 12, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Antepartum (during delivery) | 
| Maternal metabolic response | Markers of the one-carbon metabolism; B-vitamin 12, measured in micromol/l, obtained by blood withdrawal and measured in the lab. | Postpartum (6-8 weeks post delivery) | 
| Clinical maternal outcome: gestational age | Gestational age (amenorrhea duration) at delivery. | Durante partum | 
| Clinical maternal outcome: pre-eclampsia | Pre-eclampsia is defined as the combination of gestational hypertension (systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg (Korotkoff V) occurring after 20 weeks of gestation gestational age, measured twice, in a woman who previously had normal blood pressure) with proteinuria (≥ 300 mg/24 hours). | from 20 weeks of gestation to <8 weeks postpartum | 
| Clinical maternal outcome: hypertension | Hypertension is defined as a systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg (Korotkoff V) occurring after 20 weeks of gestation gestational age, measured twice, in a woman who previously had normal blood pressure. | from 20 weeks of gestation to <8 weeks postpartum | 
| Clinical maternal outcome: gestational diabetes | Gestational diabetes defined as any form of hyperglycaemia detected during pregnancy, regardless ofwhether this abnormality disappears after pregnancy. Diagnosed through a 75 gr Oral Glucose Tolerance Test (OGTT) with a fasting venous value > 7 mmol/l or above 7.8 mmol/l after 2 hours. | From the first positive pregnancy test to delivery | 
| Fetal growth | Fetal growth trajectories, Crown-Rump-Length (CRL) obtained by using ultrasound imaging. | First trimester (Between 7-7+6 days of gestational age) | 
| Fetal growth | Fetal growth trajectories, Crown-Rump-Length (CRL) obtained by using ultrasound imaging. | First trimester (Between 9-9+6 days of gestational age) | 
| Fetal growth | Fetal growth trajectories, Crown-Rump-Length (CRL) obtained by using ultrasound imaging. | First trimester (Between 11-11+6 days of gestational age) | 
| Fetal growth | Fetal growth trajectories defined as Estimated Fetal Weight (EFW) (in grams) based on the measurements (in mm) of the Head circumference (HC), Biparietal diameter (BPD), Abdominal circumference (AC) and Femur length (FL) to be obtained/measured during the ultrasound. | Second trimester (Between AD 22-25 weeks of gestational age) | 
| Fetal growth | Fetal growth trajectories defined as Estimated Fetal Weight (EFW) (in grams) based on the measurements (in mm) of the Head circumference (HC), Biparietal diameter (BPD), Abdominal circumference (AC) and Femur length (FL) to be obtained/measured during the ultrasound. | Third trimester (Between 30-33 weeks of gestational age) | 
| Histological placental function | Histology of placenta: biopsies are taken within 2 days after delivery, these are snapfrozen in -80 degrees Celsius and assessed according to protocol by pathologist | Postpartum (<2 days postpartum) | 
| Placental weight | Placental weight measured (in grams), weighed on the scale. | Postpartum (<2 days postpartum) |