Table 2. Binary and multinomial logistic regression for IVH.
The results of the multivariable regression analyses for IVH are presented. In the binary logistic regression model, lower gestational age was independently associated with higher odds of IVH, whereas sex, multiple pregnancy, mode of delivery, antenatal corticosteroid exposure, and mode of conception were not significantly associated with IVH after adjustment. In the multinomial logistic regression model assessing IVH severity, lower birth weight was independently associated with both mild (grade I-II) and severe (grade III-IV) IVH, with a stronger effect observed for severe IVH. Mode of conception by IVF was not associated with mild IVH but was strongly associated with severe IVH compared with no IVH, while no other covariates showed statistically significant independent associations with IVH severity.
*Statistical significance was set at p<0.05.
aOR, adjusted odds ratios; CI, confidence intervals; IVH, intraventricular hemorrhage; IVF, in vitro fertilization
| Binary logistic regression for IVH (yes/no) - (primary outcome; model including gestational age) | ||||||
| Variable | aOR | 95% CI | P-value | |||
| Gestational age (per 1 week) | 0.64 | 0.53-0.76 | <0.001 | |||
| Sex | 1.34 | 0.59-3.02 | 0.48 | |||
| Multiple pregnancy | 0.47 | 0.17-1.29 | 0.14 | |||
| Caesarean delivery | 0.64 | 0.28-1.45 | 0.28 | |||
| Antenatal corticosteroids | 0.81 | 0.36-1.79 | 0.60 | |||
| Mode of conception-IVF | 1.92 | 0.46-8.06 | 0.37 | |||
| Multinomial logistic regression for IVH severity (secondary outcome; reference category: no IVH; model including birth weight) | ||||||
| IVH grade III-IV vs. no IVH (mild grade) | ||||||
| Variable | aOR | 95% CI | P-value | |||
| Birth weight (per 1 g) | 998 | 0.997-0.999 | *<0.001 | |||
| Sex | 1.81 | 0.73-4.51 | 0.20 | |||
| Multiple pregnancy | 0.55 | 0.17-1.75 | 0.31 | |||
| Caesarean delivery | 0.44 | 0.17-1.09 | 0.07 | |||
| Antenatal corticosteroids | 0.88 | 0.36-2.14 | 0.78 | |||
| Mode of conception-IVF | 1.92 | 0.46-8.06 | 0.37 | |||
| IVH grade III-IV vs no IVH (severe grade) | ||||||
| Variable | aOR | 95% CI | P-value | |||
| Birth weight (per 1 g) | 994 | 0.991-0.997 | <0.001 | |||
| Sex | 3.40 | 0.83-13.90 | 0.09 | |||
| Multiple pregnancy | 0.12 | 0.01-1.22 | 0.07 | |||
| Caesarean delivery | 0.41 | 0.10-1.76 | 0.23 | |||
| Antenatal corticosteroids | 0.50 | 0.12-2.05 | 0.33 | |||
| Mode of conception-IVF | 22.6 | 2.63-195.3 | 0.004 | |||