TABLE 1.
Baseline characteristics of 100 women from the Environment and Reproductive Health Study (2007–2013) by quartile range of serum folate and vitamin B-121
| Total cohort | Serum folate, ng/mL |
Serum vitamin B-12, pg /mL |
|||
| Q1 (<16.6) | Q4 (>26.5) | Q1 (<438) | Q4 (>701) | ||
| No. of subjects | 100 | 25 | 25 | 25 | 25 |
| Personal characteristics | |||||
| Age, y | 34.7 ± 3.82 | 34.8 ± 4.5 | 34.2 ± 3.9 | 34.5 ± 4.0 | 33.8 ± 3.9 |
| BMI, kg/m2 | 24.3 ± 3.9 | 25.8 ± 5.5 | 24.0 ± 2.7 | 27.2 ± 5.2 | 22.8 ± 2.8* |
| Ever smoker, n (%) | 29 (29.0) | 4 (16.0) | 7 (28.0) | 7 (28.0) | 6 (24.0) |
| White/Caucasian, n (%) | 80 (80.0) | 21 (84.0) | 18 (72.0) | 21 (84.0) | 17 (68.0) |
| Reproductive characteristics | |||||
| Infertility diagnosis, n (%) | |||||
| Female factor | 23 (23.0) | 8 (32.0) | 7 (28.0) | 6 (24.0) | 7 (28.0) |
| Ovulation disorders | 10 (10.0) | 5 (20.0) | 2 (8.0) | 3 (12.0) | 2 (8.0) |
| DOR | 3 (3.0) | 0 (0.0) | 3 (12.0) | 1 (4.0) | 0 (0.0) |
| Tubal | 7 (7.0) | 2 (8.0) | 1 (4.0) | 2 (8.0) | 4 (8.0) |
| Endometriosis | 2 (2.0) | 0 (0.0) | 1 (4.0) | 0 (0.0) | 1 (4.0) |
| Uterine | 1 (1.0) | 1 (4.0) | 0 (0.0) | 0 (0.0) | 1 (4.0) |
| Male factor | 36 (36.0) | 10 (40.0) | 7 (28.0) | 11 (44.0) | 9 (36.0) |
| Unexplained | 41 (41.0) | 7 (28.0) | 11 (44.0) | 8 (32.0) | 9 (36.0) |
| Treatment protocol, n (%) | |||||
| Follicular phase GnRH antagonist | 11 (11.0) | 4 (16.0) | 1 (4.0) | 3 (12.0) | 5 (20.0) |
| Follicular phase GnRH agonist | 8 (8.0) | 2 (8.0) | 1 (4.0) | 4 (16.0) | 1 (4.0) |
| Luteal phase GnRH agonist | 81 (81.0) | 19 (76.0) | 23 (92.0) | 18 (72.0) | 19 (76.0) |
| Day 3 FSH, IU/L | 6.9 ± 2.0 | 7.0 ± 2.2 | 6.6 ± 1.9 | 7.0 ± 2.3 | 6.6 ± 1.9 |
| Embryo transfer day, n (%) | |||||
| No embryos transferred | 12 (12.0) | 4 (16.0) | 4 (16.0) | 3 (12.0) | 0 (0.0) |
| Day 2 | 5 (5.0) | 1 (4.0) | 0 (0.0) | 2 (8.0) | 1 (4.0) |
| Day 3 | 57 (57.0) | 14 (56.0) | 12 (48.0) | 12 (48.0) | 17 (68.0) |
| Day 5 | 26 (26.0) | 6 (24.0) | 9 (36.0) | 8 (32.0) | 7 (28.0) |
| Embryos transferred, n (%) | |||||
| No embryos transferred | 12 (12.0) | 4 (16.0) | 4 (16.0) | 3 (12.0) | 0 (0.0) |
| 1 embryo | 12 (12.0) | 3 (12.0) | 2 (8.0) | 1 (4.0) | 5 (20.0) |
| 2 embryos | 60 (60.0) | 13 (52.0) | 16 (64.0) | 16 (64.0) | 17 (68.0) |
| ≥3 embryos | 16 (16.0) | 5 (20.0) | 3 (12.0) | 5 (20.0) | 3 (12.0) |
| Dietary characteristics | |||||
| Total energy, kcal/d | 1842 ± 567 | 1961 ± 593 | 1733 ± 438 | 1891 ± 443 | 1843 ± 723 |
| Folate, μg DFE/d | 1842 ± 693 | 1665 ± 806 | 2006 ± 772 | 1920 ± 443 | 2165 ± 677* |
| Supplemental folate, μg/d | 616 ± 342 | 556 ± 439 | 680 ± 358 | 662 ± 420 | 726 ± 317 |
| Vitamin B-12, μg/d | 39 ± 109 | 74 ± 163 | 56 ± 138 | 15 ± 14 | 76 ± 169 |
| Multivitamin, n (%) | 91 (91.0) | 22 (88.0) | 23 (92.0) | 22 (88.0) | 23 (92.0) |
| Folic acid supplement, n (%) | 21 (21.0) | 4 (16.0) | 7 (28.0) | 7 (28.0) | 5 (20.0) |
1
*P < 0.05 for difference across quartiles. Differences were tested by using a Kruskal-Wallis test for continuous variables and a chi-square test for categorical variables. DFE, dietary folate equivalents; DOR, diminished ovarian reserve; FSH, follicle-stimulating hormone; GnRH, gonadotropin-releasing hormone; Q, quartile.
2
Mean ± SD (all such values).