Table 2.
Association Between TSH Level and Antithyroid Antibody Positivity With Live Birth and Pregnancy Loss Among Women With Normal fT4 (0.7–1.85 ng/dL) in the EAGeR Trial
| Modela | TSH |
Antithyroid Antibodies |
||
|---|---|---|---|---|
| Overall, RR (95% CI) | Among Pregnanciesb RR (95% CI) | Overall, RR (95% CI) | Among Pregnanciesb RR (95% CI) | |
| Live birth | ||||
| Unadjusted | 0.99 (0.87–1.12) | 0.97 (0.88–1.07) | 1.05 (0.91–1.22) | 1.03 (0.93–1.15) |
| Adjusted Model 1 | 1 (0.88–1.13) | 0.97 (0.88–1.07) | 1.03 (0.89–1.19) | 1.04 (0.94–1.16) |
| Adjusted Model 2 | 1 (0.88–1.13) | 0.97 (0.87–1.06) | 1.03 (0.89–1.19) | 1.05 (0.94–1.17) |
| Any pregnancy loss | ||||
| Unadjusted | 1.11 (0.83–1.48) | 1.09 (0.83–1.44) | 0.92 (0.63–1.35) | 0.9 (0.63–1.3) |
| Adjusted Model 1 | 1.12 (0.84–1.49) | 1.07 (0.81–1.41) | 0.91 (0.62–1.33) | 0.85 (0.59–1.22) |
| Adjusted Model 2 | 1.12 (0.84–1.49) | 1.07 (0.81–1.41) | 0.91 (0.62–1.33) | 0.85 (0.59–1.22) |
| Clinical loss | ||||
| Unadjusted | 1.29 (0.91–1.82) | 1.27 (0.91–1.77) | 0.9 (0.56–1.44) | 0.88 (0.55–1.4) |
| Adjusted Model 1 | 1.31 (0.93–1.85) | 1.26 (0.91–1.77) | 0.89 (0.56–1.43) | 0.83 (0.52–1.33) |
| Adjusted Model 2 | 1.31 (0.93–1.85) | 1.26 (0.9–1.76) | 0.89 (0.56–1.43) | 0.84 (0.53–1.33) |
Model 1 adjusts for age and body mass index, with the TSH models comparing TSH ≥2.5 vs <2.5 mIU/L, and antithyroid antibody models comparing those with positive antibodies vs negative. Adjusted model 2 adjusts for age, body mass index, and treatment assignment (LDA vs placebo).
Models restricted to women who achieved an hCG pregnancy, with inverse probability weights used control for potential selection bias introduced by restricting to women who achieved pregnancy. Weights were based on factors associated with becoming pregnancy, including age, parity, marital status, number of prior losses and treatment assignment. Weighted log-binomial regression was used to estimate RRs and 95% CIs.