Table 2. Observational and genetic associations between obesity traits and female reproductive disorders.
| Diagnosis | Obesity trait | Logistic regression | Mendelian randomisation | |||
|---|---|---|---|---|---|---|
| OR (95% CI) per 1 SD higher obesity trait | P value | Number of SNPs | OR (95% CI) per 1 SD higher obesity trait | P value | ||
| Endometriosis | BMI | 1.14 (1.12–1.16) | 4.45 × 10−29 | 264 | 1.04 (0.902–1.19) | 0.606 |
| WHR | 1.07 (1.05–1.10) | 1.00 × 10−09 | 190 | 1.24 (1.05–1.47) | 1.00 × 10−02 | |
| WHRadjBMI | 1.02 (0.99–1.04) | 0.188 | 250 | 1.24 (1.08–1.41) | 1.67 × 10−03 | |
| Heavy menstrual bleeding | BMI | 1.20 (1.18–1.22) | 7.78 × 10−117 | 268 | 1.23 (1.10–1.37) | 3.62 × 10−04 |
| WHR | 1.15 (1.13–1.16) | 8.35 × 10−69 | 191 | 1.28 (1.13–1.46) | 1.42 × 10−04 | |
| WHRadjBMI | 1.06 (1.04–1.07) | 5.30 × 10−13 | 251 | 1.16 (1.04–1.29) | 5.20 × 10−03 | |
| Infertility | BMI | 0.894 (0.852–0.936) | 2.16 × 10−07 | 267 | 0.982 (0.810–1.19) | 0.856 |
| WHR | 0.927 (0.884–0.969) | 4.08 × 10−04 | 191 | 1.10 (0.901–1.34) | 0.355 | |
| WHRadjBMI | 0.971 (0.929–1.01) | 0.176 | 251 | 1.21 (1.03–1.43) | 0.0214 | |
| Miscarriage (sporadic) | BMI | 1.03 (1.02–1.04) | 4.28 × 10−14 | 265 | 1.06 (1.01–1.12) | 0.0238 |
| WHR | 1.04 (1.04–1.05) | 3.82 × 10−24 | 190 | 0.998 (0.947–1.05) | 0.933 | |
| WHRadjBMI | 1.03 (1.02–1.04) | 1.87 × 10−13 | 250 | 0.996 (0.953–1.04) | 0.878 | |
| Miscarriage (multiple consecutive) | BMI | 254 | 0.917 (0.570–1.48) | 0.720 | ||
| WHR | 184 | 1.20 (0.743–1.92) | 0.462 | |||
| WHRadjBMI | 240 | 0.978 (0.662–1.44) | 0.911 | |||
| Polycystic ovary syndrome | BMI | 1.87 (1.80–1.94) | 1.90 × 10−64 | 268 | 1.13 (1.08–1.19) | 7.60 × 10−08 |
| WHR | 1.48 (1.41–1.55) | 3.32 × 10−26 | 191 | 1.07 (1.02–1.11) | 4.30 × 10−03 | |
| WHRadjBMI | 1.06 (0.986–1.13) | 0.124 | 251 | 1.02 (0.990–1.06) | 0.222 | |
| Pre-eclampsia | BMI | 1.25 (1.21–1.29) | 3.85 × 10−25 | 266 | 2.09 (1.60–2.73) | 5.16 × 10−08 |
| WHR | 1.13 (1.09–1.17) | 4.97 × 10−09 | 191 | 1.57 (1.16–2.10) | 2.92 × 10−03 | |
| WHRadjBMI | 1.02 (0.982–1.07) | 0.272 | 250 | 1.43 (1.13–1.80) | 2.46 × 10−03 | |
| Uterine fibroids | BMI | 1.14 (1.12–1.15) | 2.43 × 10−63 | 268 | 1.21 (1.08–1.35) | 9.93 × 10−04 |
| WHR | 1.08 (1.06–1.09) | 2.75 × 10−23 | 191 | 1.24 (1.10–1.41) | 6.20 × 10−04 | |
| WHRadjBMI | 1.02 (1.01–1.04) | 2.94 × 10−03 | 251 | 1.17 (1.06–1.29) | 1.95 × 10−03 | |
Reported P values from logistic regression and 2-sample Mendelian randomisation, testing against the null hypothesis that association ORs are equal to 1. Logistic regression models were adjusted for age, age squared, assessment centre, and smoking status. No values are reported for logistic regression of multiple miscarriage on obesity traits as these data are not available in UK Biobank. Sporadic miscarriage results for logistic regression represent stillbirth, miscarriage, and spontaneous termination in UK Biobank.
BMI, body mass index; CI, confidence interval; OR, odds ratio; SD, standard deviation; SNP, single nucleotide polymorphism; WHR, waist-to-hip ratio; WHRadjBMI, waist-to-hip ratio adjusted for BMI.