Cohort of Twin Pregnancy and the Offspring

Study Overview
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Brief Summary
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Twin pregnancy increases the risk of maternal and fetal complications, which include gestational hypertension, premature labor, twin-to-twin transfusion syndrome, intrauterine growth restriction, anemia, amniotic fluid abnormalities. Comprehensively understanding the molecular mechanisms of the disease and identification of markers contribute to development of novel therapeutic approaches. In addition, the twin pregnancy, especially the monochorionic, is an essential model of experiments of nature. This model can be applied to distinguish the epigenetic differences of twins in utero and after birth in the same genomic context. The aim of the study is to constitute a prospective cohort of twin pregnancies and the offspring.

Detailed Description
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Data are collected regarding the pregnancy data of the mother, and mental, physical and sociodemographic information of the offspring. The periods span from diagnosis of twins to 3 years old of the offspring. Biological samples would be collected including maternal blood, placental tissues, cord blood, urine, and stool from the pregnant women or the offspring at the specific time. The total estimated duration of the study is 6 years, of which the first 2.5 years will correspond to the recruitment period of the participants.

Official Title
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Cohort of Twin Pregnancy and the Offspring

Conditions
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Twin Pregnancy

Intervention / Treatment
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* Other: All pregnant women with a twin pregnancy and the offspring


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Maternal age >18 years old. Twin pregnancy. Exclusion Criteria: Fetal chromosomal or congenital abnormalities. Stillbirth.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| twins<br> | Other: All pregnant women with a twin pregnancy and the offspring<br>* No intervention<br>* Other names: No intervention;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of maternal and fetal complications | The incidence of preeclampsia, gestational diabetes mellitus, premature delivery, postpartum hemorrhage, twin to twin transfusion syndrome, selective intrauterine growth restriction. | From confirmation of pregnancy to 42 days postpartum | 
| RNA profiles in placentas of twin pregnancy measured by RNA-sequencing | Levels of placental RNA expression. | Immediately after delivery | 
| Global DNA methylation in placentas of twin pregnancy measured by whole-genome bisulfite sequencing | Global DNA methylation levels in placentas of twin pregnancy. | Immediately after delivery | 
| Protein profiles in placentas of twin pregnancy measured by tandem mass tags quantification. | Levels of proteins in placentas of twin pregnancy. | Immediately after delivery | 
| Post-translation modification of proteins in placentas of twin pregnancy measured by Integrative use of phosphoproteomics, ubiquitylproteomics and acetylproteomics. | Post-translational levels of proteins in placentas of twin pregnancy. | Immediately after delivery | 
| Metabolite profiles in placentas of twin pregnancy measured by metabolomics | Metabolite profiles in placentas of twin pregnancy. | Immediately after delivery | 
| Lipid profiles in placentas of twin pregnancy measured by lipidomic analysis | Lipid profiles in placentas of twin pregnancy. | Immediately after delivery | 
| Predictive protein markers of maternal and fetal complications in maternal blood measured by tandem mass tags quantification | Levels of specific proteins in maternal blood. | From confirmation of pregnancy to 42 days postpartum | 
| Predictive RNA markers of maternal and fetal complications in maternal blood measured by RNA-sequencing | Levels of specific RNAs in maternal blood. | From confirmation of pregnancy to 42 days postpartum | 
| Predictive metabolite markers of maternal and fetal complications in maternal blood measured by metabolomics | Levels of specific metabolites in maternal blood. | From confirmation of pregnancy to 42 days postpartum | 
| Predictive lipid markers of maternal and fetal complications in maternal blood measured by lipidomic analysis | Levels of specific lipids in maternal blood. | From confirmation of pregnancy to 42 days postpartum | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The level of twin Neurodevelopment assessed by Gesell Developmental Schedules | The parameters in Gesell Developmental Schedules including adaptive, gross motor, fine motor, language, and social function. | Age at 3 years of the offspring | 
| The incidence of long term maternal complications | Including hypertension, diabetes mellitus and metabolic disease. | Three years after delivery |