Table 3.
Prevalence of ASD by exposure, stratified by timing of antidepressant use and antidepressant class
| ASD cases | Pregnancies | Prevalence per 1,000 pregnancies (95% CI) | Crude RR (95% CI) | Adjusted RRa (95% CI) | |
|---|---|---|---|---|---|
| By timing of antidepressant use | |||||
| Unexposed | 1,500 | 154,107 | 9.7 (9.3–10.2) | 1.00 (reference) | 1.00 (reference) |
| Untreated depression | 196 | 12,994 | 15.1 (13.1–17.3) | 1.55 (1.34–1.80) | 1.51 (1.29–1.77) |
| Treated depression | |||||
| Preconception only | 91 | 6,455 | 14.1 (11.4–17.2) | 1.45 (1.17–1.79) | 1.42 (1.14–1.76) |
| During pregnancy | 355 | 18,968 | 18.7 (16.8–2.07) | 1.89 (1.68–2.11) | 1.82 (1.60–2.06) |
| First trimester only | 193 | 10,694 | 18.1 (15.6–20.7) | 1.85 (1.60–2.15) | 1.79 (1.53–2.10) |
| Second trimester only | 6 | 417 | 14.4 (5.8–29.9) | 1.48 (0.66–3.30) | 1.44 (0.64–3.21) |
| Third trimester only | 25 | 1,073 | 23.3 (15.4–33.9) | 2.40 (1.61–3.42) | 2.37 (1.59–3.53) |
| Entire pregnancy (T1–T3) | 80 | 3,927 | 20.4 (16.3–25.2) | 2.09 (1.67–2.62) | 2.00 (1.58–2.08) |
| Multiple trimesters | 51 | 3,212 | 15.9 (12.0–20.7) | 1.63 (1.23–2.16) | 1.56 (1.18–2.08) |
| Other indications for antidepressant use | |||||
| Preconception only | 3 | 385 | 7.8 (2.0–21.2) | 0.80 (0.26–2.49) | 0.80 (0.26–2.49) |
| During pregnancy | 9 | 1,230 | 7.3 (3.6–13.4) | 0.75 (0.39–1.45) | 0.71 (0.37–1.37) |
| First trimester only | 4 | 805 | 5.0 (1.6–12.0) | 0.51 (0.19–1.36) | 0.49 (0.18–1.30) |
| Second trimester only | 0 | 50 | b | b | b |
| Third trimester only | 1 | 69 | 14.5 (0.7–71.5) | 1.49 (0.21–10.58) | 1.39 (0.20–9.87) |
| Entire pregnancy (T1–T3) | 3 | 126 | 23.8 (6.1–64.8) | 2.45 (0.79–7.59) | 2.06 (0.66–6.41) |
| Multiple trimesters | 1 | 180 | 5.6 (0.3–27.4) | 0.57 (0.08–4.05) | 0.56 (0.08–4.01) |
| By antidepressant class | |||||
| Unexposed | 1,500 | 154,107 | 9.7 (9.3–10.2) | 1.00 (reference) | 1.00 (reference) |
| Untreated depression | 196 | 12,994 | 15.1 (13.1–17.3) | 1.55 (1.34–1.80) | 1.50 (1.28–1.75) |
| Treated depression | |||||
| SSRI only | 292 | 17,362 | 16.8 (14.8–18.8) | 1.73 (1.52–1.96) | 1.68 (1.46–1.92) |
| SNRI only | 13 | 1,246 | 10.4 (5.8–17.4) | 1.07 (0.62–1.85) | 1.03 (0.60–1.78) |
| TCA only | 98 | 4,856 | 20.2 (16.5–24.5) | 2.07 (1.69–2.54) | 1.95 (1.58–2.40) |
| Other antidepressants only | 3 | 115 | 26.1 (6.6–71.0) | 2.68 (0.86–8.32) | 2.38 (0.77–7.41) |
| Multiple classes | 40 | 2,199 | 18.2 (13.2–24.5) | 1.87 (1.37–2.56) | 1.78 (1.29–2.45) |
| SSRI + TCA | 21 | 1,258 | 16.7 (10.6–25.1) | 1.71 (1.11–2.64) | 1.66 (1.07–2.56) |
| SSRI + SNRI | 13 | 621 | 20.9 (11.6–3.5) | 2.15 (1.25–3.71) | 1.99 (1.15–3.45) |
| Other combinations | 6 | 320 | 18.8 (7.6–39.0) | 1.93 (0.86–4.29) | 1.86 (0.83–1.76) |
| Other indications for antidepressant use | |||||
| SSRI only | 6 | 719 | 8.3 (3.4–17.4) | 0.86 (0.38–1.93) | 0.79 (0.35–1.76) |
| SNRI only | 0 | 83 | b | b | b |
| TCA only | 6 | 761 | 7.9 (3.2–16.4) | 0.81 (0.36–1.81) | 0.78 (0.35–1.75) |
| Other antidepressants only | 0 | 2 | b | b | b |
| Multiple classes | 0 | 50 | b | b | b |
Notes:
a
Adjusted for child sex, maternal BMI, smoking status, parity, anxiety, and other psychiatric disorders.
b
Too few cases to calculate a stable estimate.
Abbreviations: ASD, autism spectrum disorder; BMI, body mass index; SNRI, serotonin and norepinephrine reuptake inhibitor; SSRI, selective serotonin reuptake inhibitor; TCA, tricyclic antidepressant.