Table 2.
Hazard Ratios and 95% CIs for the Risk of CVD According to History of Infertility Among 103 729 Women (NHSII, 1989–2017)
| Ever reported infertility | ||
|---|---|---|
| No | Yes | |
| CVD§ , || , ¶ (stroke+CHD) | ||
| Events, no | 1489 | 761 |
| Person‐years | 1 675 650 | 730 114 |
| Age‐adjusted model* | 1.00 [Referent] | 1.08 (0.99–1.18) |
| Multivariable model 1† | 1.00 [Referent] | 1.09 (0.99–1.19) |
| Multivariable model 2‡ | 1.00 [Referent] | 1.05 (0.96–1.15) |
| CHD§ , || | ||
| Events, n | 966 | 534 |
| Person‐years | 1 676 149 | 730 334 |
| Age‐adjusted model* | 1.00 [Referent] | 1.16 (1.05–1.29) |
| Multivariable model 1† | 1.00 [Referent] | 1.18 (1.06–1.32) |
| Multivariable model 2‡ | 1.00 [Referent] | 1.13 (1.01–1.26) |
| MI§ | ||
| Events, n | 512 | 270 |
| Person‐years | 1 676 709 | 730 670 |
| Age‐adjusted model* | 1.00 [Referent] | 1.10 (0.95–1.28) |
| Multivariable model 1† | 1.00 [Referent] | 1.13 (0.96–1.31) |
| Multivariable model 2‡ | 1.00 [Referent] | 1.08 (0.93–1.27) |
| Coronary revascularization|| | ||
| Events, n | 625 | 359 |
| Person‐years | 1 676 449 | 730 489 |
| Age‐adjusted model* | 1.00 [Referent] | 1.22 (1.07–1.39) |
| Multivariable model 1† | 1.00 [Referent] | 1.25 (1.09–1.43) |
| Multivariable model 2‡ | 1.00 [Referent] | 1.18 (1.03–1.35) |
| Stroke¶ | ||
| Events, n | 531 | 231 |
| Person‐years | 1 676 650 | 730 691 |
| Age‐adjusted model* | 1.00 [Referent] | 0.92 (0.79–1.07) |
| Multivariable model 1† | 1.00 [Referent] | 0.93 (0.79–1.09) |
| Multivariable model 2‡ | 1.00 [Referent] | 0.91 (0.77–1.07) |
BMI indicates body mass index; CHD, coronary heart disease; CVD, cardiovascular disease; ICD‐8, International Classification of Diseases, Eighth Revision; MI, myocardial infarction; and NHSII, Nurses’ Health Study II.
Models were jointly stratified by age (months) and calendar time (months).
Model 1 additionally adjusted for age at menarche (<12, 12, 13, ≥14 years of age), White Non‐Hispanic race and ethnicity (yes, no), marital status (ever married, never), daily aspirin use (yes, no), oral contraceptive use (never, past, current), gravidity (≤1, 2, 3, or ≥4 pregnancies), BMI at age 18 years (<19, 20.5–21.9, 22–24.9, 25–29.9, or ≥30 kg/m2), and breastfeeding duration (<3, 3–12, or >12 months).
Model 2 is additionally adjusted for time‐varying BMI (<24.9, 25–29.9, 30–34.9, or ≥35 kg/m2), cigarette smoking status and current dose (never, past, current 1–34 cigarettes/d, current ≥35 cigarettes/d), physical activity (0, 0.1–1.0, 1.1–2.4, 2.5–5.9, or ≥6 h/wk), and Alternative Healthy Eating Index 2010 diet quality score (quintiles).
Fatal and nonfatal MI and fatal coronary heart disease (ICD‐8: 410, 412).
Self‐reported coronary artery bypass grafting/angioplasty/stent.
Fatal and nonfatal cerebrovascular accident or transient ischemic attack (ICD‐8: 430–437).