Table 2.
Thyroid Hormone and Thyroid Antibody Values According to Pregnancy Trimester
| Pregnancy | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thyroid Hormones/Antibodies | First Trimester (<14 weeks) (n = 481) |
Second Trimester (14 to 28 weeks) (n = 243) |
Third Trimester (>28 weeks) (n = 297) |
|||||||||
| Mean | Median | 2.5th %ile | 97.5th %ile | Mean | Median | 2.5th %ile |
97.5th %ile |
Mean | Median | 2.5th %ile |
97.5th %ile |
|
|
Thyroid-stimulating hormone (μUI/mL) |
1.08 ± 0.69 | 0.94 | 0.41 | 2.63 | 1.20 ± 0.62 | 1.13 | 0.15 | 2.59 | 1.39 ± 0.75 | 1.29 | 0.28 | 3.48 |
|
Free triiodothyronine (pg/mL) |
3.41 ± 0.53 | 3.42 | 2.33 | 4.37 | 3.33 ± 0.45 | 3.34 | 2.42 | 4.20 | 3.22 ± 0.52 | 3.24 | 2.25 | 4.17 |
|
Free thyroxine (ng/dL) |
1.08 ± 0.14 | 1.08 | 0.84 | 1.38 | 0.94 ± 0.12 | 0.94 | 0.70 | 1.16 | 0.90 ± 0.13 | 0.89 | 0.62 | 1.17 |
|
Thyroid peroxidase antibodies (UI/mL) |
0.15 ± 0.26 | 0.08 | 0.00 | 0.74 | 0.16 ± 0.25 | 0.09 | 0.00 | 0.89 | 0.19 ± 0.43 | 0.09 | 0.00 | 1.20 |
|
Thyroglobulin antibodies (UI/mL) |
1.05 ± 0.65 | 0.83 | 0.40 | 3.12 | 0.95 ± 0.62 | 0.76 | 0.34 | 2.65 | 0.89 ± 0.51 | 0.76 | 0.38 | 2.48 |