Reprod Biomed Online. 2024 Jul 22;49(6):104382. doi: 10.1016/j.rbmo.2024.104382. Online ahead of print.
ABSTRACT
RESEARCH QUESTION: What are the risk factors for a prolonged third stage of labour, closely related to postpartum haemorrhage, and what is the effect of assisted reproductive technology (ART) on the third stage of labour?
DESIGN: Clinical data of women who delivered vaginally at term at 12 primary maternity hospitals in Japan (2010-2018) (n = 25,336) were obtained; 1148 (4.5%) conceived through ART and 2246 (8.9%) through non-ART treatments. The risk of a prolonged third stage of labour (defined as ≥20 min) was evaluated by univariable and multivariable regression analyses. Adjusted odds ratios (aOR) of a prolonged third stage of labour were evaluated, stratified by the type of ART, with natural conception as a reference.
RESULTS: Multivariable analysis showed that pregnancy achieved through ART (aOR 4.38, 95% CI 3.12 to 6.15), history of spontaneous miscarriage (OR 1.40, 95% CI 1.06 to 1.84) and prolonged labour (OR 1.52, 95% CI 1.09 to 2.12) were identified as independent risk factors. Frozen embryo transfer (FET), FET in a hormone replacement cycle (HRC-FET) and blastocyst-stage embryo transfer were significantly associated with a prolonged third stage of labour (aOR 4.07, 95% CI 2.75 to 6.04, aOR 4.11, 95% CI 2.58 to 6.57 and aOR 2.13, 95% CI 1.15 to 3.95, respectively). No significant difference was observed in the duration of third stage of labour between natural conception and non-ART treatment (P = 0.61).
CONCLUSION: Pregnancy achieved through ART, particularly FET, HRC-FET and blastocyst-stage embryo transfer, was a significant risk factor for a prolonged third stage of labour.
PMID:39369451 | DOI:10.1016/j.rbmo.2024.104382
