Table 2.
Participants characteristics by birth outcome.
| LB (n = 38) | NLBa (n = 54) | p LB vs. all NLBb | p NP vs. PLb | |||
|---|---|---|---|---|---|---|
| All NLB (n = 54) | NP (n = 46) | PL (n = 8) | ||||
| Median female age in years (IQR) | 33.5 (28.7–36.3) | 36.8 (31.8–39.8) | 36.8 (31.6–39.8) | 35.8 (32.5–40.6) | 0.016 | 0.990 |
| Median female BMI in kg/m2 (IQR)c | 23.0 (21.4–24.9) | 24.0 (21.8–26.6) | 23.8 (21.8–26.7) | 24.9 (21.3–27.0) | 0.136 | 0.951 |
| Median duration of infertility in mo (IQR) | 29.0 (22.5–43.5) | 30.0 (23.0–43.0) | 28.0 (21.8–39.8) | 40.0 (31.5–57.3) | 0.953 | 0.021 |
| Female smokers, n (%) | 3 (7.9) | 5 (9.3) | 4 (8.7) | 1 (12.5) | 1.000 | 0.567 |
| Type of infertility of the female, n (%)d | 0.835 | 0.063 | ||||
| Primary | 22 (57.9) | 30 (55.6) | 23 (50.0) | 7 (87.5) | ||
| Secondary | 16 (42.1) | 24 (44.4) | 23 (50.0) | 1 (12.5) | ||
| Cause of infertility, n (%) | 0.188 | 0.181 | ||||
| Unexplained | 15 (39.5) | 23 (42.6) | 17 (37.0) | 6 (75.0) | ||
| Male factor | 22 (57.9) | 24 (44.4) | 22 (47.8) | 2 (25.0) | ||
| Othere | 1 (2.6) | 7 (13.0) | 7 (15.2) | 0 | ||
| Median # previous embryo transfers per participant (IQR) | 2.0 (1.0–3.0) | 1.0 (1.0–3.0) | 1.5 (1.0–3.0) | 1.0 (1.0–2.0) | 0.352 | 0.322 |
Significant values are in [bold].
BMI body mass index, IQR interquartile range, LB live birth, mo months, NLB no live birth, NP no pregnancy, PL pregnancy loss.
Only samples with ≥ 100 16S rRNA sequencing reads (V1–V2 region) were included.
aThe NLB participants included participants with a pregnancy loss (PL) as well as participants who did not get pregnant at all (NP).
bContinuous variables were compared by Wilcoxon rank sum test and categorical variables by Fisher’s exact test.
cData was missing for one participant in the LB group.
dPrimary: female has never conceived before. Secondary: female has conceived before.
eOther causes of infertility are tubal factor (NLB n = 1), ovulatory disorder (LB n = 1, NLB n = 2), endometriosis (NLB n = 1) and mixed causes (NLB n = 3).