Table 4. Stepwise multiple linear regression analysis examining the influence of perinatal factors on variation in lnTSH.
| Variable | Coefficient | SE | P-value |
|---|---|---|---|
| (Constant) | 1.252 | 0.103 | <0.001 |
| ln 17OHP | 0.178 | 0.028 | <0.001 |
| 1st babya) | –0.106 | 0.040 | 0.008 |
| Sample time | –0.005 | 0.002 | 0.025 |
| Vacuum deliveryb) | 0.101 | 0.049 | 0.042 |
lnTSH, log transformed TSH; SE, standard error; ln17OHP, log transformed 17-α hydroxyprogesterone.
a)1st baby in comparison with 2nd or later baby. b)Vacuum assisted delivery in comparison with normal spontaneous delivery.