The impact of season, temperature, and direct normal irradiance on IVF pregnancy outcomes: a retrospective cohort study.

IF 3 3区地球科学 Q2 BIOPHYSICS

International Journal of Biometeorology Pub Date : 2025-08-01 Epub Date: 2025-06-18 DOI:10.1007/s00484-025-02951-2

Chao Wang, Jiehua Chen, Zhong Lin, Li Shi, Qiuyan Ruan, Jiamin Long, Yanping Lao, Xiangli Niu

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引用次数: 0

Abstract

Objective: This study assessed associations between season, temperature, direct normal irradiance (DNI), and clinical pregnancy outcomes in first fresh in vitro fertilization (IVF) cycle. Methods. We conducted a retrospective cohort study (June 2021-October 2023) of 1179 patients undergoing fresh IVF cycles. Inclusion criteria required age ≤ 45 years, first-time fresh embryo transfer cycles (long/antagonist protocol), excluding preimplantation genetic testing, frozen cycles, or incomplete data. Temperature and DNI were recorded from gonadotropin (Gn) initiation to oocyte retrieval. Binary logistic regression assessed seasonal impacts on clinical pregnancy, while restricted cubic splines (RCS) independently modeled temperature/DNI effects. Results. Compared to winter, clinical pregnancy likelihood was 1.74-fold higher in spring (95% CI:1.11-2.71, P = 0.015) and 1.53-fold in summer (95% CI:1.02-2.30, P = 0.042). Stratified analysis revealed a 2.02-fold increased likelihood in summer cycles using the long protocol (95% CI:1.07-3.82, P = 0.031), whereas no seasonal variation was observed in antagonist protocol. RCS regression analysis indicated a nonlinear relationship between temperature and clinical pregnancy outcomes, which was confirmed in the long protocol group. No significant correlations were observed with DNI or in patients treated with the antagonist protocol. Conclusions. Season and ambient temperature significantly impact IVF clinical pregnancy, especially in the long protocol, with the highest increase in pregnancy rates observed in summer, as well as within the 26.13℃ to 29.68℃ temperature range. No significant effects were observed with DNI or the antagonist protocol. These findings suggest that summer treatment may optimize IVF outcomes, but future studies should prioritize multi-center prospective designs with continuous temperature monitoring to define precise optimal ranges.

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季节、温度和直接正常辐照度对IVF妊娠结局的影响：一项回顾性队列研究。

目的：本研究评估了第一次体外受精（IVF）周期中季节、温度、直接正常辐照度（DNI）与临床妊娠结局之间的关系。方法。我们进行了一项回顾性队列研究（2021年6月至2023年10月），纳入了1179例接受新鲜试管婴儿周期的患者。纳入标准要求年龄≤45岁，首次新鲜胚胎移植周期（长期/拮抗剂方案），排除植入前基因检测，冷冻周期或不完整的数据。从促性腺激素（Gn）起始到卵母细胞回收，记录温度和DNI。二元logistic回归评估了季节对临床妊娠的影响，而限制三次样条（RCS）独立模拟了温度/DNI的影响。结果。与冬季相比，春季临床妊娠可能性高1.74倍（95% CI:1.11 ~ 2.71, P = 0.015），夏季临床妊娠可能性高1.53倍（95% CI:1.02 ~ 2.30, P = 0.042）。分层分析显示，使用长方案，夏季周期的可能性增加2.02倍（95% CI:1.07-3.82, P = 0.031），而在拮抗剂方案中，没有观察到季节性变化。RCS回归分析显示温度与临床妊娠结局之间存在非线性关系，这在长方案组得到证实。与DNI或使用拮抗剂方案治疗的患者没有观察到显著相关性。结论。季节和环境温度显著影响IVF临床妊娠，特别是在长时间方案中，夏季以及26.13℃至29.68℃温度范围内的妊娠率升高最高。未观察到DNI或拮抗剂方案的显著影响。这些发现表明，夏季治疗可能会优化IVF结果，但未来的研究应优先考虑多中心前瞻性设计，并进行连续温度监测，以确定精确的最佳范围。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

International Journal of Biometeorology 地学-环境科学

CiteScore

6.40

自引率

9.40%

发文量

183

审稿时长

1 months

期刊介绍： The Journal publishes original research papers, review articles and short communications on studies examining the interactions between living organisms and factors of the natural and artificial atmospheric environment. Living organisms extend from single cell organisms, to plants and animals, including humans. The atmospheric environment includes climate and weather, electromagnetic radiation, and chemical and biological pollutants. The journal embraces basic and applied research and practical aspects such as living conditions, agriculture, forestry, and health. The journal is published for the International Society of Biometeorology, and most membership categories include a subscription to the Journal.