An observational study in Iodine Deficiency, Thyroid and Pregnancy Related, sponsored by University of Minho. Active, not recruiting at 10 sites in Portugal. Open to female participants aged 18 Years to 50 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2024-11-15.
Sponsored by University of Minho · Observational
Full intellectual capabilities are achieved only if crucial nutrients are present during development. Iodine deficiency is the most common cause of preventable brain harm in infants. Because of its critical need during pregnancy, several countries implemented programs of iodine supplementation in preconception and pregnancy. In 2013, the prevalence of iodine deficiency in Portugal has led health authorities to issue a recommendation for iodine supplementation. This study aims to evaluate the impact of iodine supplementation on maternal and fetal iodine status and thyroid function, obstetric outcomes, quality of breast milk and child psychomotor development. It also intends to evaluate whether the time of iodine supplementation initiation influences all the above-mentioned parameters. The novelty and relevance of this study reside on the number of women/child and on the extent of health parameters that will be evaluated. The information collected will contribute to the detailed characterization of thyroid hormone homeostasis throughout pregnancy and its relationship with iodine supplementation (including time of initiation). The data will provide evidence on whether this iodine supplementation strategy impacted on iodine sufficiency of the mother and the newborns, or if it needs re-evaluation.
Iodine is essential for intellectual development. Its deficiency, alone, is the most frequent cause of preventable brain harm in infants. Iodine is required to synthesize thyroid hormones, key components of central nervous system development. Because of its relevance in pregnancy, several countries have implemented iodine supplementation programs in preconception, pregnancy and lactation.
Iodine deficiency has been previously shown in women of childbearing age in Portugal. Because of this, since 2013 the National Health Authorities have recommended supplementing iodine (200 ug/day) in preconception, pregnant and lactating women. However, the latest Cochrane review on the subject does not allow to conclude on whether iodine supplementation strategies implemented to date are efficient. Therefore, this study is of great public health interest.
The objectives are to:
To achieve these aims the investigators will follow: i) 304 women longitudinally, before, during the three trimesters of pregnancy (primary care Health Centres), at delivery and three months after delivery, ii) their children at birth, 3 and 12 months of age; ii) perform a detailed evaluation of parameters of thyroid function (mother and child) and of psychomotor development of the newborns.
Investigators expect to provide detailed characterization of thyroid hormone homeostasis before and throughout pregnancy, their relation with iodine supplementation (and its timing of administration, if any) and with thyroid hormone parameters and psychomotor development of the newborn.
With 6 years passed since the beginning of recommendation on iodine supplementation, this is an appropriate time to assess its effectiveness. The high number of samples and parameters to analyze make this a high-power study to support public health policies.
20 studies on the registry are indexed under Psychomotor Disorders; 6 are open to participants now.
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Women from community health centers who intend to become pregnant or become pregnant and intend to delivery in the Hospital de Braga.
Exclusion Criteria:
Women in preconception, pregnant and lactating, receiving iodine supplementation
Dietary Supplement: Iodine supplementation
Women in preconception, pregnant or lactating, not receiving iodine supplementation
Women of childbearing age not planning to become pregnant.
Recommendation, issued by the National Health Authorities, on supplementing with iodine (200 ug/day) women during preconception, pregnancy and lactation.
Prevalence of iodine deficiency in pregnant women and in women of childbearing age in the Minho region
Urinary iodine.
Time frame: At baseline in women recruited for pregnancy follow-up and in women in childbearing age not planning to become pregnant.
Impact of iodine supplementation on maternal serum parameters of thyroid function and urinary iodine in the first trimester of pregnancy
Serum thyroid hormones (TSH, total and free T4, total and free T3, thyroxine-binding globulin, human chorionic gonadotropin, thyroglobulin, anti-thyroglobulin, anti-thyroperoxidase), urinary iodine.
Time frame: First trimester of pregnancy
Bayley scale assessed psychomotor development at one year of age
Bayley psychomotor development scale
Time frame: One year of age
Serum parameters of thyroid function, urinary iodine and thyroid ultrasound characterization throughout pregnancy
Serum thyroid hormones (TSH, total and free T4, total and free T3, thyroxine-binding globulin, human chorionic gonadotropin, thyroglobulin, anti-thyroglobulin, anti-peroxidase), urinary iodine, thyroid ultrasound.
Time frame: Serum thyroid hormones and urinary iodine before iodine supplementation (if any), 1st, 2nd, 3rd trimesters of pregnancy, after delivery. Thyroid ultrasound at baseline, 3rd trimester and 3 months after delivery.
Serum parameters of thyroid function, urinary iodine and thyroid ultrasound characterization of newborns
Serum thyroid hormones (TSH and eventually total and free thyroxine as retrieved from the neonatal newborn screening) and urinary iodine.
Time frame: One to 3 days of age (if full term babies), 1 to 3 days and 4th week of age (in premature and low birth weight babies).
Iodine and energy composition of human milk 3 months after delivery
Iodine and energy composition (total proteins, lipids and carbohydrates).
Time frame: Three months after delivery
Fetal heart rate and thyroid volume at age 3 months
Fetal cardiotocography and thyroid ultrasound.
Time frame: Fetal cardiotocography at 36-40 weeks of gestation and thyroid ultrasound at 3 months of age.
Plan to share: Yes — Data that underlie results in a publication.
Supporting information: Study protocol
This study is active, not recruiting, as verified in Nov 2024. You cannot join it, but the record below documents what was studied.
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