Comparison of infertility treatments* exposure according to sociodemographic characteristics
| n (%)† | P values | |
| Mother | ||
| Age (years) | ||
| <20 | 32 (0.0) | <0.001 |
| 20–29 | 738 (0.8) | |
| 30–34 | 723 (4.4) | |
| 35–39 | 418 (5.0) | |
| ≥40 | 159 (6.3) | |
| Geographic al origin | ||
| France | 990 (3.3) | 0.557 |
| North Africa | 408 (2.7) | |
| Sub-Saharan Africa | 282 (2.8) | |
| Other | 387 (4.4) | |
| Occupation | ||
| None | 558 (1.4) | 0.003 |
| Professional | 470 (5.5) | |
| Intermediate | 385 (2.3) | |
| Administrative/public service | 223 (3.1) | |
| Other | 328 (4.6) | |
| Gravidity | ||
| 1 | 710 (4.5) | 0.080 |
| 2 | 623 (3.1) | |
| >2 | 740 (2.4) | |
| Diabetes mellitus | ||
| No | 1971 (3.4) | 0.770 |
| Yes | 97 (2.1) | |
| Pregnancy | ||
| Multiplicity | ||
| Singletons | 1980 (2.0) | <0.001 |
| Multiple | 94 (31.9) | |
| Small for gestational age | ||
| No | 1792 (2.8) | 0.001 |
| Yes | 280 (6.8) | |
| Vaginal bleeding | ||
| No | 1953 (3.5) | 0.561 |
| Yes | 23 (4.4) | |
| Invasive prenatal screening | ||
| No | 1632 (3.3) | 0.675 |
| Yes | 438 (3.7) | |
| Prenatal diagnosis of congenital heart defect | ||
| No | 1630 (3.6) | 0.260 |
| Yes | 444 (2.5) | |
| Induced labo u r | ||
| No | 1743 (3.6) | 0.204 |
| Yes | 322 (2.2) | |
| Elective caesarean section | ||
| No | 1808 (2.9) | 0.005 |
| Yes | 255 (6 | |
*Infertility treatments included induction of ovulation, in vitro fertilisation and intracytoplasmic sperm injection.
†% calculated with the total of cases or controls without missing data as a denominator.