Table 1.
Demographic and reproductive characteristics by quartiles of caffeine intake.
| Number of Women | Quartile of Caffeine Intake (range, mg/day)
|
p-value1 | ||||
|---|---|---|---|---|---|---|
| Total Cohort | Q1 (0–70) | Q2 (71–141) | Q3 (142–230) | Q4 (231–816) | ||
| 340 | 84 | 86 | 87 | 84 | ||
| Age2, yrs | 31.5 (4.0) | 31.2 (4.2) | 30.7 (4.0) | 31.9 (4.3) | 32.2 (3.4) | 0.06 |
| BMI, kg/m2 | 23.4 (4.5) | 23.2 (4.9) | 23.1 (3.7) | 23.3 (4.9) | 24.0 (4.5) | 0.56 |
| Current Smoker, n (%) | 61 (17.9) | 5 (6.0) | 19 (22.1) | 14 (16.1) | 23 (27.7) | 0.002 |
| Native Born, n (%) | 256 (75.3) | 68 (81.0) | 70 (81.4) | 60 (69.0) | 58 (69.9) | 0.10 |
| Years of Education | 15.4 (2.7) | 15.1 (2.8) | 15.1 (2.8) | 15.8 (2.6) | 15.5 (2.9) | 0.33 |
| Type of Work, n (%) | 0.72 | |||||
| Education | 59 (17.4) | 16 (19.1) | 11 (12.8) | 20 (23.0) | 12 (14.5) | |
| Healthcare | 37 (10.9) | 8 (9.5) | 11 (12.8) | 11 (12.6) | 7 (8.4) | |
| Office work | 161 (47.4) | 38 (45.2) | 45 (52.3) | 37 (42.5) | 41 (49.4) | |
| Other | 83 (24.4) | 22 (26.2) | 19 (22.1) | 19 (21.8) | 23 (27.7) | |
| Gravidity, n (%) | 0.25 | |||||
| 0 | 145 (42.7) | 35 (41.7) | 35 (40.7) | 44 (50.6) | 31 (37.4) | |
| 1 | 102 (30.0) | 24 (28.6) | 31 (36.1) | 25 (28.7) | 22 (26.5) | |
| ≥2 | 93 (27.4) | 25 (29.8) | 20 (23.3) | 18 (20.7) | 30 (36.1) | |
| Parity, n (%) | 0.61 | |||||
| 0 | 208 (61.2) | 50 (59.6) | 54 (62.8) | 58 (66.7) | 46 (55.4) | |
| 1 | 96 (28.2) | 23 (27.4) | 25 (29.1) | 23 (26.4) | 25 (30.1) | |
| ≥2 | 36 (10.6) | 11 (13.1) | 7 (8.1) | 6 (6.9) | 12 (14.5) | |
| Years of Infertility | 1.4 (1.8) | 1.3 (1.7) | 1.3 (1.5) | 1.3 (1.8) | 1.7 (2.2) | 0.45 |
| Previous IVF Attempts, n (%) | 0.08 | |||||
| 0 | 212 (62.4) | 48 (57.1) | 56 (65.1) | 62 (71.3) | 46 (55.4) | |
| 1 | 71 (20.9) | 25 (29.8) | 17 (19.8) | 12 (13.8) | 17 (20.5) | |
| ≥2 | 57 (16.8) | 11 (13.1) | 13 (15.1) | 13 (14.9) | 20 (24.1) | |
| Infertility Diagnosis, n (%) | 0.38 | |||||
| Male | 115 (33.8) | 30 (35.7) | 32 (37.2) | 29 (33.3) | 24 (28.9) | |
| Female | 39 (11.5) | 10 (11.9) | 6 (7.0) | 10 (11.5) | 13 (15.7) | |
| Unexplained | 57 (16.8) | 9 (10.7) | 12 (14.0) | 17 (19.5) | 19 (22.9) | |
| PGD | 129 (37.9) | 35 (41.7) | 36 (41.9) | 31 (35.6) | 27 (32.5) | |
| Antagonist Protocol, n (%) | 330 (97.1) | 80 (95.2) | 85 (98.8) | 84 (96.6) | 81 (97.6) | 0.55 |
| FSH Ampules | 25.8 (17.8) | 25.6 (20.8) | 23.7 (11.1) | 26.5 (16.1) | 27.4 (21.7) | 0.57 |
| Embryo Transfer Day, n (%) | 0.16 | |||||
| 2 | 12 (3.5) | 3 (3.6) | 6 (7.0) | 0 (0.0) | 3 (3.6) | |
| 3 | 199 (58.5) | 46 (54.8) | 44 (51.2) | 56 (64.4) | 53 (63.9) | |
| 43 | 129 (37.9) | 35 (41.7) | 36 (41.9) | 31 (35.6) | 27 (32.5) | |
| Number of Embryos Transferred, n (%) | 0.63 | |||||
| 0 | 53 (15.6) | 11 (13.1) | 16 (18.6) | 18 (20.7) | 8 (9.6) | |
| 1 | 114 (33.5) | 29 (34.5) | 30 (34.8) | 29 (33.3) | 26 (31.3) | |
| 2 | 159 (46.8) | 40 (47.6) | 38 (44.2) | 37 (42.5) | 44 (53.0) | |
| 3–4 | 14 (4.2) | 4 (4.8) | 2 (2.3) | 3 (3.5) | 5 (6.0) | |
| ≥1 Top Quality Embryos Transferred, n (%) | 236 (69.4) | 64 (76.2) | 57 (66.3) | 56 (64.4) | 59 (71.1) | 0.34 |
1
Differences across categories were tested using an ANOVA test for continuous variables and a Chi Square test for categorical variables
2
Data are presented as mean (standard deviation) or number of women (%) unless otherwise specified.
3
All day 4 embryo transfers were PGD cycles.