TABLE 2—
Summary of Meta-Analysis Results Regarding Spina Bifida per 100 000 Births by Birth Population and Fortification Status: World Population, 1985–2010
| Variable and Group | No. of Studies | Estimate per 100 000 Births (95% CI) |
| Fortification: mandatory | ||
| LB | 14 | 33.86 (31.05, 36.92) |
| LB + SB | 13 | 30.37 (27.42, 33.63) |
| LB + SB + TOP | 14 | 35.22 (32.18, 38.56) |
| Fortification: not mandatory | ||
| LB | 34 | 48.35 (41.07, 56.93) |
| LB + SB | 37 | 47.74 (43.66, 52.20) |
| LB + SB + TOP | 49 | 52.29 (46.28, 59.08) |
| Continent: Africa | ||
| LB | 2 | 78.18 (30.66, 202.55) |
| LB + SB | 1 | 54.32 (36.71, 80.39) |
| LB + SB + TOP | . . . | . . . |
| Continent: Asia | ||
| LB | 6 | 81.37 (35.05, 188.90) |
| LB + SB | 14 | 87.99 (66.83, 115.86) |
| LB + SB + TOP | 4 | 243.14 (48.34, 1223.04) |
| Continent: Australia | ||
| LB | 1 | 37.69 (10.51, 135.21) |
| LB + SB | 1 | 51.48 (42.98, 61.66) |
| LB + SB + TOP | 4 | 61.66 (51.44, 73.91) |
| Continent: Europe | ||
| LB | 5 | 59.76 (39.19, 91.12) |
| LB + SB | 2 | 59.54 (32.98, 107.49) |
| LB + SB + TOP | 22 | 52.73 (45.43, 61.21) |
| Continent: North America | ||
| LB | 29 | 36.87 (34.36, 39.55) |
| LB + SB | 23 | 36.08 (33.50, 38.87) |
| LB + SB + TOP | 29 | 38.70 (34.41, 43.53) |
| Continent: South America | ||
| LB | . . . | . . . |
| LB + SB | 3 | 81.33 (59.56, 111.06) |
| LB + SB + TOP | . . . | . . . |
Notes. CI = confidence interval; LB = live birth; SB = stillbirth; TOP = termination of pregnancy. The pooled period prevalence of spina bifida in studies reporting on live births, stillbirths, and terminations of pregnancy was lower in regions with mandatory folic acid fortification than in those without (35.22 per 100 000 live births compared with 52.29 per 100 000 live births, respectively).