Table 2.
Infertility diagnoses and treatment parameters
| Singletons at birth | Twins at birth | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Reference group* | Excess ET | Reference group* | Excess ET | ||||||
| Excess FHB | Excess FHB | ||||||||
| Embryos transferred (ET) | 1 | 2 | ≥3 | >1 | 2 | 3 | ≥4 | >2 | |
| Fetal heartbeats (FHB) | 1 | 1 | 1 | ≥2 | 2 | 2 | 2 | ≥3 | |
| N, children | 23,753 | 38,019 | 14,464 | 5437 | 42,851 | 9008 | 2720 | 2183 | |
| Infertility | Male factor | 32.5 | 35.4 | 35.3 | 33.9 | 35.4 | 37.0 | 34.3 | 36.2 |
| Diagnoses (%) | Endometriosis | 7.6 | 10.6 | 11.6 | 10.6 | 10.2 | 12.9 | 11.3 | 11.4 |
| Ovulation disorders | 15.3 | 16.1 | 11.8 | 15.2 | 17.7 | 13.4 | 11.5 | 13.4 | |
| Diminished ovarian reserve | 22.5 | 20.8 | 26.5 | 23.7 | 20.3 | 21.1 | 28.0 | 23.3 | |
| Tubal ligation | 0.9 | 1.7 | 2.1 | 1.7 | 2.0 | 1.9 | 1.9 | 2.6 | |
| Tubal—other | 10.5 | 12.8 | 13.9 | 12.8 | 12.2 | 13.0 | 16.1 | 13.5 | |
| Uterine factor | 4.6 | 4.5 | 5.3 | 5.0 | 4.5 | 5.6 | 6.6 | 4.8 | |
| Unexplained | 18.5 | 15.5 | 14.3 | 15.2 | 15.2 | 14.4 | 14.0 | 15.4 | |
| Other—RFA** | 10.4 | 9.3 | 10.4 | 10.3 | 9.0 | 9.8 | 10.5 | 9.3 | |
| Noninfertile*** | 0.8 | 0.5 | 0.3 | 0.6 | 0.5 | 0.3 | 0.1 | 0.2 | |
| Number of diagnoses (%) | One | 76.7 | 74.8 | 71.5 | 73.3 | 75.0 | 73.4 | 69.7 | 73.2 |
| Two or more | 22.3 | 24.8 | 28.0 | 26.1 | 24.5 | 26.1 | 30.2 | 26.7 | |
| Missing | 1.0 | 0.4 | 0.4 | 0.6 | 0.5 | 0.5 | 0.1 | 0.1 | |
| Sperm source (%) | Partner | 45.7 | 70.3 | 78.8 | 73.3 | 75.2 | 79.4 | 79.4 | 80.3 |
| Mixed | 0.1 | 0.2 | 0.4 | 0.2 | 0.2 | 0.4 | 0.7 | 0.6 | |
| Donor | 2.5 | 3.3 | 4.5 | 5.1 | 3.3 | 3.5 | 5.7 | 4.4 | |
| Missing | 51.7 | 26.2 | 16.4 | 21.5 | 21.3 | 16.8 | 14.2 | 14.6 | |
| Assisted hatching (%) | None | 61.7 | 67.1 | 41.8 | 62.4 | 73.6 | 50.1 | 33.5 | 47.5 |
| Some | 0.8 | 2.7 | 4.5 | 3.3 | 2.4 | 4.2 | 6.4 | 5.7 | |
| All | 37.4 | 30.2 | 53.7 | 34.2 | 24.0 | 45.6 | 60.1 | 46.7 | |
| ICSI (%) | None | 18.4 | 22.6 | 23.0 | 24.6 | 5.3 | 5.3 | 7.6 | 5.8 |
| Some | 1.9 | 5.0 | 5.1 | 4.6 | 48.1 | 54.7 | 54.9 | 54.1 | |
| All | 27.8 | 46.0 | 55.6 | 49.3 | 21.4 | 16.9 | 14.2 | 14.7 | |
| Missing | 51.8 | 26.3 | 16.4 | 21.6 | 25.1 | 23.1 | 23.3 | 25.3 | |
| Oocyte | Autologous | 87.9 | 86.6 | 93.9 | 85.6 | 82.5 | 89.9 | 92.4 | 89.4 |
| Donor | 12.1 | 13.4 | 6.1 | 14.4 | 17.5 | 10.1 | 7.6 | 10.6 | |
| Embryo state (%) | Fresh | 48.2 | 73.7 | 83.6 | 78.5 | 78.6 | 83.2 | 85.7 | 85.4 |
| Source (%) | Thawed | 51.8 | 26.3 | 16.4 | 21.5 | 21.4 | 16.8 | 14.3 | 14.6 |
| Day of transfer (%) | Cleavage stage (days 2–3) | 16.6 | 42.1 | 75.9 | 46.1 | 30.2 | 68.9 | 80.2 | 67.2 |
| (Autologous-fresh only) | Blastocyst stage (days 5–6) | 81.9 | 56.3 | 21.1 | 52.3 | 68.4 | 27.6 | 14.1 | 27.2 |
*Reference group, ET=1 and FHB=1 for singletons at birth and ET=2 and FHB=2 for twins at birth
**Other RFA includes immunologic, chromosomal, or other serious disease
***Noninfertile includes single parent or same sex parents