Table 1 Baseline characteristics of 225 couples from the EARTH study in relation to female smoking status
From: Discrete survival model analysis of a couple’s smoking pattern and outcomes of assisted reproduction
| Female Smoking Status | P-value a | |||
|---|---|---|---|---|
| Never smoker | Former smoker | Current smoker | ||
| Number of couples, n (%) | 167 (74.2) | 51 (22.7) | 7 (3.1) | <0.001 |
| Total ART cycles, n (%) | 249 (70.3) | 93 (26.3) | 12 (3.4) | <0.001 |
| Female Characteristics b | ||||
| Age, years | 35 (32, 38) | 34 (33, 37) | 34 (29, 37) | 0.89 |
| Body Mass Index, kg/m2 | 22.6 (20.4, 26.3) | 22.7 (21.5, 24.7) | 25.7 (23.8, 28.2) | 0.11 |
| At least college education, n (%) | 148 (88.6) | 39 (76.5) | 5 (71.4) | 0.04 |
| Non-Hispanic Caucasian, n (%) | 143 (85.6) | 43 (84.3) | 7 (100) | 0.74 |
| Pack-years | NA | 1.6 (0.5, 4.6) | 2.4 (1.0, 4.2) | 0.65 |
| Total smoking duration, years | NA | 9 (5, 13) | 14 (8, 16) | 0.08 |
| Average cigarettes smoked | NA | 4.0 (1.5, 10.0) | 5.0 (1.5, 7.0) | 0.89 |
| Age of smoking initiation, years | NA | 17 (15, 18) | 18 (18, 20) | 0.04 |
| Total Smoking cessation, years | NA | 8.0 (5.0, 12.0) | 0.2 (0.2, 0.2) | <0.001 |
| Exposed to passive smoking, n (%) | 30 (18.0) | 14 (27.5) | 2 (28.6) | 0.23 |
| Male Partner Characteristics | ||||
| Partner age, years | 36 (33, 40) | 35 (33, 40) | 39 (35, 41) | 0.40 |
| Partner body mass index, kg/m2 | 26.9 (24.2, 29.3) | 26.9 (24.5, 29.3) | 27.9 (25.1, 28.3) | 0.97 |
| Partner former smoker, n (%) | 38 (22.8) | 16 (31.4) | 1 (14.3) | 0.44 |
| Partner current smoker, n (%) | 8 (4.8) | 4 (7.8) | 4 (57.1) | <0.001 |
| Baseline Reproductive Characteristics | ||||
| Previous IUI, n (%) | 71 (42.5) | 19 (37.3) | 2 (28.6) | 0.70 |
| Previous IVF, n (%) | 40 (24.0) | 8 (15.7) | 1 (14.3) | 0.51 |
| ICSI, n (%) | 83 (49.7) | 31 (60.8) | 4 (57.1) | 0.37 |
| Infertility diagnosis, n (%) | 0.47 | |||
| Male factor | 55 (32.9) | 20 (39.2) | 4 (57.1) | |
| Diminished ovarian reserve | 9 (5.9) | 3 (5.9) | 1 (14.3) | |
| Endometriosis | 10 (6.0) | 3 (5.9) | 0 (0.0) | |
| Ovulatory dysfunction | 15 (9.0) | 5 (9.8) | 0 (0.0) | |
| Tubal causes | 11 (6.6) | 8 (15.7) | 1 (14.3) | |
| Uterine causes | 3 (1.8) | 0 (0.0) | 0 (0.0) | |
| Unexplained | 64 (38.3) | 12 (23.5) | 1 (14.3) | |
| Initial treatment protocol, n (%) | 0.69 | |||
| Antagonist | 21 (12.6) | 5 (9.8) | 1 (14.3) | |
| Flare | 17 (10.2) | 8 (15.7) | 0 (0.0) | |
| Luteal phase agonist | 129 (77.3) | 38 (75.5) | 6 (85.7) | |
| Day 3 FSH levels, IU/L | 6.6 (5.8, 8.0) | 7.3 (6.0, 8.8) | 8.1 (7.0, 8.3) | 0.16 |
| E2 Trigger levels, pmol/L | 2126 (1632, 2639) | 1828 (1459, 2532) | 1798 (1540, 1953) | 0.17 |
| Day of embryo transfer, n (%) | 0.01 | |||
| No transfer | 11 (6.6) | 4 (7.8) | 2 (28.6) | |
| Day 2 | 4 (2.4) | 5 (2.2) | 0 (0.0) | |
| Day 3 | 79 (47.6) | 29 (56.9) | 1 (14.3) | |
| Day 5 | 72 (43.4) | 13 (25.5) | 4 (57.1) | |
| Number of embryos transferred, n (%) | <0.001 | |||
| No transfers | 11 (6.6) | 4 (7.8) | 2 (28.6) | |
| 1 embryo | 42 (25.3) | 2 (3.9) | 2 (28.6) | |
| 2 embryos | 81 (48.8) | 41 (80.4) | 3 (42.7) | |
| 3 or more embryos | 32 (19.3) | 4 (7.8) | 0 (0.0) | |