B-vitamin Levels and Adverse Pregnancy Outcomes

Study Overview
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Brief Summary
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This prospective nested case-control study aims to examine the effects of blood vitamin B levels in first-trimester pregnant women on the pregnancy outcomes

Detailed Description
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Folate deficiency can cause severe adverse pregnancy outcomes, such as neural tube defects. Effective folate functioning requires essential metabolic interactions with other B vitamins including vitamin B2, vitamin B3, vitamin B6, and vitamin B12, which can also influence pregnancy outcomes independently. For example, animal and family studies have identified that niacin (B3) deficiency can lead to congenital malformations. However, how folate and related B-vitamin levels interact with each other while affecting various pregnancy outcomes including abortion, birth defects, pregnancy complications, etc. is unclear. Besides, folate levels in previous studies were mostly measured in plasma which are easily influenced by dietary factors, instead of red blood cell folate which can reflect the long-term status. Moreover, the difference in the risk of neural tube defects across a range of maternal red blood cell folate concentrations has been largely ignored. Using data of pregnant women recruited at Beijing Obstetrics and Gynecology Hospital from December 2020 to December 2021, this case-control study aims to examine the association of folate and related B-vitamin levels in first-trimester blood samples (plasma and red blood cell) with pregnancy outcomes, particularly the association between niacin deficiency and birth defects.

Official Title
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The Association Between Niacin Deficiency and Birth Defects: a Case-control Study

Conditions
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Pregnancy Loss, Pregnancy Complications, Pregnancy Induced Hypertension, Recurrent Pregnancy Loss, Health Problems in Pregnancy, Gestational Diabetes, Gestational Hypertension, Preterm Birth, Birth Defect

Intervention / Treatment
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* Other: No intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Pregnant women with 6-13(+6 days) gestational weeks Resided in Beijing in the past year Pregnant women who intend to have antenatal examinations and delivery at Beijing Obstetrics and Gynecology Hospital Pregnant women who are willing to participate in this study with informed consent Exclusion Criteria: Women with Hepatitis B, syphilis, HIV/AIDS and other infectious diseases.

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

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Case group<br>Case group with certain pregnancy outcome, e.g., miscarriage, stillbirth, preterm birth, and birth defects,gestational hypertension, gestational diabetes mellitus, etc. | Other: No intervention<br>* This is an observational study without any intervention<br>|
| Control group<br>Control group without certain pregnancy outcome,e.g., miscarriage, stillbirth, preterm birth, and birth defects,gestational hypertension, gestational diabetes mellitus, etc. | Other: No intervention<br>* This is an observational study without any intervention<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| fetal outcomes | Including intrauterine growth retardation,abortion, stillbirth, preterm birth, live birth | at delivery | 
| fetal outcomes | Including birth defects | 42 days after delivery | 
| maternal outcomes | Including gestational hypertension, preeclampsia, gestational diabetes mellitus, hypothyroidism | at delivery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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vitamin B, pregnancy outcome