Table 3.
Odds ratios of LBW by univariate analysis of predictor variables.
| Predictor variable | OR (95% CI) | P value |
|---|---|---|
| Maternal age | 1.024(0.986-1.064) | 0.226 |
| Maternal BMI | 1.035(1.003-1.068) | 0.034* |
| Infertility duration | 0.996(0.946-1.049) | 0.883 |
| Parity | ||
| 0 | 1 | |
| ≥1 | 0.688(0.435-1.088) | 0.11 |
| FET cycle rank | ||
| 0 | 1 | |
| ≥1 | 0.96(0.742-1.243) | 0.759 |
| Infertility type | ||
| Primary | 1 | |
| Secondary | 0.838(0.67-1.048) | 0.121 |
| Infertility cause | ||
| Female factor | 1 | |
| Male factor | 1.086(0.824-1.43) | 0.558 |
| Mixed | 0.903(0.649-1.256) | 0.545 |
| Unexplained | 1.46(0.921-2.317) | 0.108 |
| EMT | ||
| 7.5<EMT ≤ 12 | 1 | |
| EMT ≤ 7.5 | 2.564(1.59-4.135) | <0.001* |
| EMT >12 | 0.592(0.415-0.845) | 0.004* |
| Fertilization type | ||
| IVF | 1 | |
| ICSI | 1.036(0.81-1.326) | 0.776 |
| Endometrial preparation protocols | ||
| NC | 1 | |
| HRT | 1.329(0.951-1.856) | 0.096 |
| GnRH agonist-HRT | 1.298(0.903-1.865) | 0.159 |
| No. of transferred embryos | ||
| 1 | 1 | |
| 2 | 0.962(0.776-1.192) | 0.72 |
| Stage of embryo transferred | ||
| Cleavage stage | 1 | |
| Blastocyst stage | 1.208(0.946-1.542) | 0.129 |
| No. of good-quality embryo transfer | ||
| 0 | 1 | |
| ≥1 | 1.068(0.863-1.321) | 0.548 |
| Cesarean delivery | ||
| No | 1 | |
| Yes | 1.302(1.002-1.693) | 0.049* |
| Newborn gender | ||
| Male | 1 | |
| Female | 1.467(1.184-1.817) | <0.001* |
| Pregnancy complications | ||
| No | 1 | |
| Yes | 7.151(5.706-8.961) | <0.001* |
OR, odds ratio; CI, confidence interval; BMI, body mass index; FET, frozen embryo transfer; EMT, endometrial thickness; IVF, in vitro fertilization; ICSI, intracytoplasmic sperm injection; NC, natural cycle; HRT, hormone replacement therapy; GnRH, gonadotropin-releasing hormone.
*P < 0.05 was considered statistically significant.