Table1 Baseline characteristics of the study population
|  | Characteristics | Levels | Overall (N = 106,640) | |
|---|---|---|---|---|
N | % | |||
Female | Age (y) | ≤ 29 | 28,459 | 26.7 |
30–34 | 41,852 | 39.2 | ||
35–37 | 18,065 | 16.9 | ||
38–40 | 10,577 | 9.9 | ||
41–42 | 4118 | 3.9 | ||
≥ 43 | 3569 | 3.5 | ||
BMI (kg/m2) | 18.5–24.0 | 66,463 | 62.3 | |
< 18.5 | 8423 | 7.9 | ||
24.0–28 | 23,480 | 22.0 | ||
≥ 28 | 8274 | 7.8 | ||
Gravidity | 0 | 62,692 | 59.0 | |
1 | 23,579 | 22.1 | ||
≥ 2 | 20,099 | 18.8 | ||
Parity | 0 | 99,279 | 93.1 | |
≥ 1 | 7361 | 6.9 | ||
Fallopian tube disorders | Â | 22,874 | 21.4 | |
Uterine disorders | Â | 8041 | 7.5 | |
Hyperprolactinemia | Â | 424 | 0.4 | |
Ovulatory disorders | Â | 13,917 | 13.1 | |
Ovarian cyst surgery | Â | 305 | 0.3 | |
Diminished ovarian function | Â | 10,312 | 9.7 | |
Endometriosis | Â | 5817 | 5.5 | |
Genetic disorders | Â | 977 | 0.9 | |
Abnormal gestational history | Â | 948 | 0.9 | |
Male | Age (y) | ≤ 45 | 102,106 | 95.7 |
> 45 | 4534 | 4.3 | ||
BMI (kg/m2) | < 18.5 | 1513 | 1.4 | |
18.5–24.0 | 37,240 | 34.9 | ||
24.0–28.0 | 45,187 | 42.4 | ||
≥ 28.0 | 22,700 | 21.3 | ||
Ejaculatory disorders | Â | 149 | 0.1 | |
Teratozoospermia | Â | 4680 | 4.4 | |
Sperm quality | Normal | 56,788 | 53.2 | |
OAZ | 38,675 | 36.3 | ||
Severe OAZ | 3398 | 3.2 | ||
Azoospermia | 7779 | 7.3 | ||
ART | Infertility type | Primary | 58,545 | 54.9 |
Secondary | 48,095 | 45.1 | ||
ART failure history | No | 70,040 | 65.7 | |
Yes | 36,600 | 34.3 | ||
Ovulation induction protocol | Stimulation cycle | 101,349 | 95.0 | |
Minimal-stimulation cycle | 4639 | 4.4 | ||
Natural cycle | 652 | 0.6 | ||
Antral follicle count | > 12 | 36,479 | 34.2 | |
5–12 | 61,786 | 57.9 | ||
< 5 | 8337 | 7.9 | ||
Number of oocytes retrieved | ≥ 20 | 15,770 | 14.8 | |
5–20 | 77,398 | 72.6 | ||
< 5 | 13,472 | 12.6 | ||
Insemination method | ICSI | 47,137 | 44.2 | |
IVF | 59,503 | 55.8 | ||