Clinical Trial Details
— Status: Recruiting
Administrative data
NCT number |
NCT04215406 |
Other study ID # |
XJTU1AF-CRF-2019-023 |
Secondary ID |
|
Status |
Recruiting |
Phase |
|
First received |
|
Last updated |
|
Start date |
January 1, 2020 |
Est. completion date |
June 30, 2023 |
Study information
Verified date |
August 2021 |
Source |
First Affiliated Hospital Xi'an Jiaotong University |
Contact |
Wenfang Yang, PHD |
Phone |
0086-029-85323223 |
Email |
wenfang.yang[@]xjtu.edu.cn |
Is FDA regulated |
No |
Health authority |
|
Study type |
Observational
|
Clinical Trial Summary
This research evaluates the effects of maternal exposure to air pollution during pregnancy on
adverse pregnancy outcomes, the general demographic information, the level of maternal
exposure to air pollution, pregnancy-related information, the occurrence of adverse pregnancy
outcomes, and serum indicators of pregnant women during pregnancy are collected. Finally, the
research explores that whether the inflammatory cytokine and hormone can mediate the
occurrence of adverse pregnancy outcomes under the maternal exposure to air pollution during
pregnancy.
Description:
Pregnancy is the most important period in the life process. China have a high occurrence of
adverse pregnancy outcomes and the situation of air pollution is not optimistic. With the
introduction of perspective in environment and health, the impact of air pollution on health
has received extensive attention. A large number of studies have confirmed that maternal
exposure to air pollution during pregnancy such as particulate matter (PM), nitrogen dioxide
(NO2), sulfur dioxide (SO2), ozone (O3), carbon monoxide (CO) can increase the risk of
miscarriage, gestational diabetes mellitus(GDM), hypertensive disorder complicating
pregnancy, preterm birth and low birth weight(LBW). Maternal exposure to air pollution was
also closely related to birth defects, newborn congenital hypothyroidism, and affect
neurodevelopment in offspring. In other respects, studies shown that air pollution can change
maternal steroid hormone levels (human chorionic gonadotropin (hCG), luteinizing hormone
(LH), follicle-stimulating hormone (FSH), estradiol(E2) and progesterone(P)), which play an
important role in maintaining pregnancy and the developing of adverse pregnancy outcomes.
Interleukin (IL) is an important inflammatory mediator cytokine, IL-8, IL-6 and IL-2 are
closely related to the reproductive process of mammals and may regulate the occurrence of
adverse pregnancy outcomes and influenced by air pollution, but limited studies focused on
them in regulating the occurrence of adverse pregnancy outcomes under exposure to air
pollution. So, a prospective cohort study is conducted to explore the new mechanism of
adverse pregnancy outcomes affected by air pollution.
Research content: This research is a prospective cohort study from January 2020 to December
2022, 288 pregnant women will be recruited from the First Affiliated Hospital of Xi'an
Jiaotong University. A health management birth cohort will be established. The subjects will
be enrolled within 6 weeks of gestation, and be followed up about 9 months: ①To construct a
spatial and temporal series about adverse pregnancy outcomes influenced by maternal exposure
to air pollution during pregnancy; ②To explore the effects of maternal exposure to air
pollution on hormone and inflammatory cytokine during pregnancy, and the relationship between
maternal level of hormone, inflammation cytokine and adverse pregnancy outcomes; ③To
determine if maternal hormone and inflammatory cytokine mediate the occurrence of adverse
pregnancy outcomes during pregnancy under maternal exposure to air pollution as intermediate
regulatory product.
Research meaning:①To explore the mechanism of adverse pregnancy outcomes affected by air
pollution during pregnancy, provide an epidemic evidence for interposing the occurrence of
adverse pregnancy outcomes by regulating maternal hormone and inflammatory cytokine; ②To
define the critical period of the developing of adverse pregnancy outcomes in spatial and
temporal series, and to calculate the cutoff value of air pollution on adverse pregnancy
outcomes, propose short-term control target of air pollution related to maternal and child
health, construct the first-level prevention strategy for adverse pregnancy outcomes.
Research steps: ① Complete the recruiting of subjects, which meet the inclusion and exclusion
criteria sign an informed consent before the carrying out of research; ② Follow up: Three
questionnaires will be conducted at the end of each trimester to acquire the information
including sociodemographic characteristics, menstrual history and childbearing history,
residence during pregnancy, lifestyle and diet habits, the information of illness and
medication, history of past illness, etc. Then the maternal exposure level of air pollutants
in every trimester will be calculated, based on air pollution detection station, from Shaanxi
Meteorological and Environment Bureau according to residence information of participants; ③
Serum indicators: fasting venous blood samples will be taken at different time points to
detect serum level of maternal hormone and inflammatory cytokine, all the venous blood
samples will be taken and tested in the laboratory of First Affiliated Hospital of Xi'an
Jiaotong University. 4 mL of fasting venous blood sample are needed, and the blood sample
will be put in dry test tubes, centrifuged within 1 hour, and the separated serum was stored
at -20 ° C, chemiluminescence and ELASA will be adapted to detect the samples respectively. ④
Monitoring of adverse pregnancy outcomes: closely monitor the occurrence of adverse pregnancy
outcomes during pregnancy. During the whole study period, the subjects could withdraw the
cohort at any time.
Abortion: The abortion includes early spontaneous abortion (occur within 12 weeks of
gestation), late spontaneous abortion (occur from 12 weeks to 28 weeks of gestation) and
missed abortion included(embryo die in the uterine cavity and fail to excrete themselves at
time); Maternal adverse pregnancy outcomes: hypertension disorders of pregnancy (gestational
hypertension, preeclampsia, eclampsia, chronic hypertension), GDM (referring to diabetes
occur in pregnancy and the glucose metabolism is normal before pregnancy). Adverse outcomes
for fetus or newborn: including preterm birth (delivery form 28 weeks to 37 weeks of
gestation); low birth weight (newborn weight measured within 72 hours after birth is less
than 2500 grams); birth defects (fetal structural, functional or metabolic abnormalities,
also known as congenital malformations).
Statistical method: ①Univariate analysis: The maternal exposure levels of air pollution
during pregnancy will be treated as independent variables, pregnancy outcomes will be treated
as dependent variables, univariate logistic regression will be used to analyze the
relationship between them; Then, maternal exposure levels will be treated as independent
variables, maternal hormone and inflammatory cytokine as the dependent variable, the
univariate logistic regression analysis will be used to analyze the relationship between
them; Finally, the level of hormone and inflammatory cytokine will be treated as independent
variables, pregnancy outcomes as dependent variables, and analyze the relationship between
them; ②Multivariate analysis: adverse pregnancy outcomes will be taken as dependent
variables, maternal exposure levels, sociodemographic characteristics, nutritional status,
dietary status, and other factors are included as independent variables, the multivariate
logistic regression analysis will be used to data analysis. In the multivariate regression
the odds ration value and 95% confidence intervention of air pollution to affect adverse
pregnancy outcomes will be calculated adjusted for sociodemographic characteristics,
nutrition, dietary conditions and other factors; ③Analysis of intermediary factor: mediate
effect analysis will be used to analyze whether the maternal hormone and inflammatory
cytokine mediate the occurrence of adverse pregnancy outcomes as intermediate regulatory
products under maternal air pollution exposure; ④ Spatial and temporal series analysis will
be adapted to define the critical period of the developing of adverse pregnancy outcomes
under maternal exposure to air pollution, and calculate the cut-off value of air pollution
about the adverse pregnancy outcomes.
Research planning: ①Complete research design, follow-up questionnaires, and pre-experiments
before 2020; ②Complete enrollment of subjects, follow-up of the study subjects, detecting of
serum indicators, monitor the occurrence of adverse pregnancy outcomes before January 2021;
③Complete data export and analysis about basic information and data analysis; ④Clarify the
relationship between maternal air pollution exposure during pregnancy and adverse pregnancy
outcomes, explore the potential mechanism in the occurrence of adverse pregnancy outcomes
influenced by air pollution.