Table 3.
Association between ART characteristics and birth defects among ART-conceived births.
| Characteristics | Levels | No. of birth | No. of birth defects (%) | aRR (95%CI)a | P valuea |
|---|---|---|---|---|---|
| Infertility Diagnosis | |||||
| Duration of infertility, month | <36 | 753 | 105 (13•9) | 1•00 | |
| ≥36 | 799 | 112 (14•0) | 1•06 (0•77–1•46) | 0•728 | |
| PCOS | No | 1368 | 193 (14•1) | 1•00 | |
| Yes | 184 | 24 (13•0) | 0•91 (0•53–1•56) | 0•728 | |
| Ovarian dysfunction | No | 1404 | 189 (13•5) | 1•00 | |
| Yes | 148 | 28 (18•9) | 1•52 (0•93–2•50) | 0•095 | |
| Endometriosis | No | 1441 | 209 (14•5) | 1•00 | |
| Yes | 111 | 8 (7•2) | 0•45 (0•22–0•95) | 0•037 | |
| Pelvic or tubal factor | No | 344 | 49 (14•2) | 1•00 | |
| Yes | 1208 | 168 (13•9) | 0•96 (0•66–1•38) | 0•814 | |
| Uterine factor | No | 1061 | 152 (14•3) | 1•00 | |
| Yes | 491 | 65 (13•2) | 0•85 (0•60–1•20) | 0•347 | |
| Thyroid factor | No | 1492 | 205 (13•7) | 1•00 | |
| Yes | 60 | 12 (20•0) | 1•74 (0•87–3•48) | 0•115 | |
| Sperm disorder | No | 622 | 100 (16•1) | 1•00 | |
| Yes | 930 | 117 (12•6) | 0•84 (0•61–1•15) | 0•275 | |
| ART Procedure | |||||
| Cycle type | Fresh | 295 | 38 (12•9) | 1•00 | |
| Frozen | 1257 | 179 (14•2) | 1•07 (0•71–1•61) | 0•756 | |
| Number of embryos transferred | One | 367 | 57 (15•5) | 1•00 | |
| Two or more | 1185 | 160 (13•5) | 0•87 (0•62–1•22) | 0•427 | |
| Stage of embryo transferred | Cleavage | 671 | 82 (12•2) | 1•00 | |
| Blastocyst | 881 | 135 (15•3) | 1•17 (0•85–1•62) | 0•327 | |
| Fertilization method | IVF | 1143 | 162 (14•2) | 1•00 | |
| ICSI | 395 | 55 (13•9) | 0•98 (0•69–1•41) | 0•934 | |
| PGD | No | 1521 | 215 (14•1) | 1•00 | |
| Yes | 31 | 2 (6•5) | 0•38 (0•09–1•61) | 0•187 | |
| Assisted hatching | No | 466 | 52 (11•2) | 1•00 | |
| Yes | 1086 | 165 (15•2) | 1•26 (0•88–1•82) | 0•208 | |
| Regimen of ovulation induction | GnRH-a | 712 | 80 (11•2) | 1•00 | |
| GnRHant | 750 | 119 (15•9) | 1•48 (1•05–2•09) | 0•024 | |
| Microstimulation | 90 | 18 (20•0) | 2•11 (1•13–3•93) | 0•019 | |
| Medication Usage | |||||
| GnRH agonist doses | – | 1552 | 217 (14•0) | 0•91 (0•79–1•05) | 0•176 |
| GnRHant doses | – | 1552 | 217 (14•0) | 1•13 (0•87–1•47) | 0•351 |
| Gn doses, per 1000IU | – | 1552 | 217 (14•0) | 1•01 (0•78–1•31) | 0•956 |
| Gn type | FSH only | 767 | 107 (14•0) | 1•00 | |
| FSH+LH | 126 | 17 (13•5) | 0•88 (0•48–1•62) | 0•685 | |
| hMG | 656 | 92 (14•0) | 1•10 (0•79–1•53) | 0•581 | |
| Clomiphene | No | 1494 | 205 (13•7) | 1•00 | |
| Yes | 58 | 12 (20•7) | 1•65 (0•83–3•26) | 0•153 | |
| Growth hormone | No | 1483 | 202 (13•6) | 1•00 | |
| Yes | 69 | 15 (21•7) | 1•71 (0•88–3•33) | 0•117 |
Abbreviation: PCOS, polycystic ovary syndrome; IVF, in vitro fertilization; ICSI, intracytoplasmic sperm injection; PGD, preimplantation genetic diagnosis; GnRH-a, gonadotropin-releasing hormone agonist; GnRHant, gonadotropin-releasing hormone antagonist; Gn, gonadotropin; FSH, follicle stimulating hormone; LH, luteinizing hormone; hMG, human chorionic gonadotropin.
a Analyses were adjusted for maternal age, parity, maternal pre-pregnancy BMI, diabetes and hypertension.