Environmental Pollutants in Pregnancy - IoMumNEXT

Globally 12.6 million people, including 1.7 million children under the age of 5, die each year from environmental-related illnesses. Prenatal exposure to environmental chemical pollutants has been associated with perinatal mortality, prematurity, low birth weight, congenital malformations, neurobehavioral function disorder and metabolic disorders. This project aims: a) to evaluate exposure to environmental pollutants during pregnancy; and, b) to study the association of this exposure with anthropometry and neurodevelopment of the offspring, up to 6 years of age. This study will be based on a population of 1000 pregnant women whose recruitment has already started under the IoMum project (clinical trials #NCT04010708), previously approved by Ethics Commitee of Centro Hospitalar e Universitário São João/Faculdade de Medicina da Universidade do Porto (#292-17). Maternal urine samples collected in the 1st and 3rd trimesters of pregnancy will be used. Maternal urinary concentrations of toxic metals and pesticide metabolites will be determined and neurodevelopmental outcomes will be evaluated as well as anthropometric parameters of children from birth to 6 years of age. The results of this project will contribute to the characterization of the exposure of Portuguese pregnant women to environmental pollutants as well as to the knowledge on the association between isolated or cumulative exposure to these pollutants and the health of the offspring.

IoMumNEXT is a prospective observational study which will take advantage of our previous IoMum project - monitoring of iodine status in Portuguese pregnant women: impact of supplementation (Clinical Trials record: NCT04010708), a prospective observational study that has set up a cohort of 1155 pregnant women, living in the Porto and Lisbon Metropolitan Areas.

In a subsample of 199 pregnant women of this IoMum@Porto cohort it was already possible to conclude that:

1. 19 and 32% of women had urinary levels (first trimester) of lead (208Pb) and arsenic (75As), respectively above the corresponding reference values (\> 4 microg / L for Pb and\> 35 microg / L for As).
2. Maternal urinary Pb levels (first trimester) revealed a positive association with birth weight and length.
3. Maternal urinary levels of As (first trimester) revealed a positive association with head circumference at birth.
4. In a subsample of 69 pregnant women, 52% showed urinary 3-Phenoxybenzoic acid (3-PBA) levels above the detection level.

In addition to Pb, As and 3-PBA, the maternal urinary concentrations of other pollutants such as the elements lithium (7Li), cadmium (111Cd) and mercury (80Hg), and the pesticide metabolite trichloro-pyridinol (TCPY) will be analyzed. The continuity of this work will allow an important scientific advance, regarding the association between exposure to environmental pollutants and the physical and neurobehavioral development of children.

This proposal is in line with goal 3 (Health and well-being) of the United Nations Agenda 2030.

The study population will be composed of the pregnant women from the IoMum cohort as well as by their children born from this cohort. Maternal urine samples collected in the first trimester (T1) and third trimesters (T2) of pregnancy will be used, as well as urine samples from children collected between 3 and 6 years of age. Sociodemographic, lifestyle, anthropometric and health data will continue to be collected between 3 and 4 years of age (T3) and between 5 and 6 years of age (T4). Additionally, neurodevelopment will be assessed by Vineland adaptative behaviour scale at T3 and T4.

Eligibility Criteria:
Inclusion Criteria:

* Have had single live birth
* Have provided contact and a urine sample T1
* Have provided consent to participate at T1
* Have provided consent to participate at T3

Exclusion Criteria:

Pregnancy complications

* Congenital malformations
* Gestational diabetes