Gestational Age Specific Thyroid Function Reference Range

Gestational Age Specific Thyroid Function Reference Range in Hong Kong

Status

Completed

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT03663517

Enrollment

599

Registered

2018-09-10

Start date

2014-07-02

Completion date

2016-04-30

Last updated

2018-09-10

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Pregnancy, Reference Values, Thyroid

Keywords

Thyroid, Reference values, Pregnancy

Brief summary

It has been well accepted that maternal thyroid dysfunction has adverse affects on both mothers and fetuses. However, the dramatical changes during pregnancy make the interpretation of thyroid function test (TFT, i.e. free triiodothyronine \[FT3\], free thyroxine \[FT4\] and thyrotropin \[TSH\]) very difficult. Previous studies have shown that the level of thyroid hormones differs from non-pregnant population and varies from gestational ages. Moreover, studies have shown the agreement among different instrument platforms was quite low. This study is aimed to determine gestational age specific TFT reference ranges of the local pregnant population for all available platforms currently used under Hospital Authority and Department of Health.

Interventions

None listed

Study design

Observational model

ECOLOGIC_OR_COMMUNITY

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

FEMALE

Age

16 Years to 50 Years

Healthy volunteers

Yes

Inclusion criteria

* Pregnant women receiving pregnancy and postnatal care in the Department of Obstetrics & Gynaecology, Prince of Wales Hospital, Hong Kong

Exclusion criteria

* 1\. Previous history of thyroid dysfunction (hypothyroidism or hyperthyroidism); * 2\. Autoimmune disease, particularly those receiving corticosteroid or immunosuppressant: e.g. systemic lupus erythematosus; * 3\. Disease associated with thyroid dysfunction: e.g. molar pregnancy

Design outcomes

Primary

Measure	Time frame	Description
Change of free triiodothyronine (FT3) during pregnancy	At the time of booking for antenatal visit (1st trimester), oral glucose tolerance test (24-32 weeks), admission for delivery (3rd trimester) and a gestational age assigned randomly.	gestational FT3 level
Change of free thyroxine (FT4) during pregnancy	At the time of booking for antenatal visit (1st trimester), oral glucose tolerance test (24-32 weeks), admission for delivery (3rd trimester) and a gestational age assigned randomly.	gestational FT4 level
Change of thyrotropin (TSH) during pregnancy	At the time of booking for antenatal visit (1st trimester), oral glucose tolerance test (24-32 weeks), admission for delivery (3rd trimester) and a gestational age assigned randomly.	gestational TSH level

Outcome results