Table 4.
Perinatal outcome by the three data sources, Finland 1996–1998, %1)
| MBR | IVF statistics | IVF research data | |
| Births | 3535 | 3557 | 3594 |
| - singletons | 2735 | 2765 | 2819 |
| - multiples | 800 | 792 | 775 |
| Premature births (< 37 weeks), N | 582 | 623 | 634 |
| % | 16.5 | 17.5 | 17.6 |
| - among singletons | 8.7 | 8.5 | 9.4 |
| - among multiples | 43.1 | 49.0 | 47.7 |
| Newborns | 4331 | 4383 | 4384 |
| - singletons | 2735 | 2765 | 2819 |
| - multiples | 1596 | 1618 | 1565 |
| Low birth weight (< 2500 grams), N | 836 | 906 | 856 |
| % | 19.3 | 20.7 | 19.5 |
| - among singletons | 6.0 | 5.9 | 6.4 |
| - among multiples | 42.2 | 46.2 | 43.1 |
| Small-for-gestational age, N | n.a. | 301 | 305 |
| % | n.a. | 6.9 | 7.0 |
| - among singletons | n.a. | 2.4 | 3.1 |
| - among multiples | n.a. | 15.4 | 14.4 |
| Birth weight, g | |||
| Mean (SD) | n.a. | 3085 (787) | 3090 (781) |
| - among singletons | n.a. | 3440 (625) | 3421 (644) |
| - among multiples | n.a. | 2475 (650) | 2494 (640) |
| Perinatal mortality, N | 61 | 54 | 56 |
| per 1000 newborns | 14.1 | 12.3 | 12.8 |
| - among singletons | 8.8 | 8.3 | 8.5 |
| - among multiples | 23.8 | 20.4 | 21.1 |
| Major congenital anomaly cases, N | 68 | 185 | 179 |
| per 10 000 newborns | 157 | 422 | 409 |
1) The following comparisons are statistically significant: - IVF statistics vs. MBR: Premature births among multiples P = 0.019. Low birth-weight among multiples P = 0.002. Major congenital anomaly cases P < 0.001. - IVF statistics vs. IVF research data: Major congenital anomaly cases P < 0.001. - MBR vs. IVF research data: Low birth-weight among multiples P = 0.013. n.a. = not available