Table 1.
Characteristics of women who have a recalled TTP available for analysis compared with those without a recalled TTP (Total N=202)a. All characteristics were measured at enrollment into EPS Phase 1 or during Phases 1 and 2.
| Recalled TTP available N=154 (76%) | Recalled TTP not availableb N=48 (24%) | P-value from the multivariable modelc | |
|---|---|---|---|
| EPS Phase 1 outcome | |||
| Did not conceive within 6 months | 35 (74) | 12 (26) | |
| Recognized miscarriaged | 14 (74) | 5 (26) | |
| Live birthd | 105 (77) | 31 (23) | |
| Prospective TTPe | |||
| 1 | 44 (83) | 9 (17) | 0.08 |
| 2 | 33 (87) | 5 (13) | |
| 3 – 4 | 33 (70) | 14 (30) | |
| 5 – 7 | 17 (63) | 10 (37) | |
| 8 – 12 | 13 (76) | 4 (24) | |
| ≥13 | 14 (70) | 6 (30) | |
| Age | |||
| < 29 | 76 (79) | 20 (21) | |
| ≥ 29 | 78 (74) | 28 (26) | |
| Race | |||
| Asian or Pacific Islander, Black, or other | 5 (62) | 3 (38) | |
| White | 149 (77) | 45 (21) | |
| Education | |||
| High school graduate or less | 6 (46) | 7 (54) | 0.45 |
| Some college or college graduate | 92 (74) | 32 (26) | |
| At least some graduate school | 56 (86) | 9 (14) | |
| Occupation | |||
| Sales/Service/Factory | 12 (67) | 6 (33) | 0.003 |
| Other white collar | 60 (71) | 25 (29) | |
| Teaching | 23 (92) | 2 (8) | |
| Management/Administration | 9 (47) | 10 (53) | |
| Health professional | 39 (91) | 4 (9) | |
| Academia/Science | 11 (92) | 1 (8) | |
| Body mass index (kg/m2) | |||
| < 20 | 61 (81) | 14 (19) | 0.26 |
| 20- < 25 | 83 (76) | 26 (24) | |
| ≥ 25 | 10 (56) | 8 (44) | |
| Gravidityc | |||
| 0 | 56 (80) | 14 (20) | 0.01 |
| 1 | 60 (85) | 11 (15) | |
| ≥ 2 | 38 (62) | 23 (38) | |
| Parityc | |||
| 0 | 75 (79) | 20 (21) | 0.04 |
| 1 | 64 (79) | 17 (21) | |
| ≥ 2 | 15 (58) | 11 (42) | |
| Smoking | |||
| Never | 110 (79) | 29 (21) | 0.008 |
| Current | 3 (25) | 9 (75) | |
| Former | 41 (80) | 10 (20) | |
| Alcohol intake (drinks per month) | |||
| 0 - 1 | 61 (73) | 23 (27) | |
| 2 – 8 | 81 (80) | 20 (20) | |
| > 8 | 12 (71) | 5 (29) | |
| Caffeine intake (mg/month) | |||
| 0 - 1480 | 45 (82) | 10 (18) | 0.24 |
| > 1480 - < 6900 | 82 (80) | 21 (20) | |
| ≥ 6900 | 27 (61) | 17 (39) |
This table excludes the 19 women (of 221) who did not complete Phase 1.
TTP is unavailable for women who were deceased at Phase 3 (N=11), did not respond to the Phase 3 questionnaire (either by mail or by phone) (N=31), or responded to the questionnaire but did not provide an estimate of TTP (N=6).
The multivariable logistic regression model only included variables that were important (p ≤ 0.2) in the univariable analysis: prospective TTP, education, occupation, BMI, gravidity, parity, smoking and caffeine intake. Gravidity and parity were estimated in separate models. With the exception of parity, p-values are estimated from the model that includes gravidity (and not parity).P-values are from a likelihood ratio test which indicates whether the tested characteristics differ between those with and without recalled time-to-pregnancy data.
Among women who conceived within 6 months.
One woman with a prospective TTP of >6 was classified as 5-7 cycles.