Table 3.
Odds ratio for any birth defects according to type of assisted conception and multiplicity
| Newborns with birth defects | Unudjusted | Adjusted | ||
|---|---|---|---|---|
| Type of assisted conception | N | % | OR (95%CI) | OR (95%CI)* |
| Spontaneous conception (reference category) | 11,964 | 4.4 | – | – |
| Any type of non spontaneous conception | 472 | 6.7 | 1.55 (1.4–1.7) | 0.95 (0.8–1.1) |
| Medically induced ovulation only | 25 | 5.6 | 1.27 (0.8–1.9) | 1.15 (0.7–1.8) |
| IUI | 35 | 5.4 | 1.24 (0.9–1.7) | 0.89 (0.6–1.3) |
| GIFT | 3 | 5.9 | 1.35 (0.4–4.3) | 1.22 (0.3–5.3) |
| FIVET | 168 | 7.7 | 1.79 (1.5–2.1) | 1.00 (0.8–1.2) |
| ICSI | 202 | 6.7 | 1.55 (1.3–1.8) | 0.97 (0.8–1.2) |
| Other or missing | 39 | 5.5 | 1.25 (0.9–1.7) | 0.69 (0.5–1.0) |
All models were calculated excluding cases with missing categories
OR Odds ratio; CI Confidence Interval
*Adjusted for maternal age, citizenship, maternal and paternal education, parity, fetal sex, course of pregnancy, gestational age, birth–weight, single or multiple delivery (the last one just for the model including all births)