ArticleJournal of assisted reproduction and genetics2020
Seasonal variation, temperature, day length, and IVF outcomes from fresh cycles.
Article in Journal of assisted reproduction and genetics, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
14 citing papers in PubMed, 1 synthesis or guideline pooled it, 19 citations in OpenAlex.
- Association between season and pregnancy outcomes in fresh embryo transfer cycles: a systematic review and meta-analysis.Frontiers in public health · 2025Pooled it
- The association between heat waves and pregnancy outcome among women undergoing assisted reproductive technology in Sichuan, China.BMC public health · 2026Article
- Association between ambient temperature exposure and pregnancy outcomes in participants undergoing IVF: a retrospective cohort study.Journal of assisted reproduction and genetics · 2026Article
- Extreme ambient heat and outcomes of assisted reproduction in the continental United States, 1996 to 2018.Environmental research · 2026Article
- Effects of different seasons on the outcome ofFrontiers in reproductive health · 2026Article
- The impact of season, temperature, and direct normal irradiance on IVF pregnancy outcomes: a retrospective cohort study.International journal of biometeorology · 2025Article
- The impact of seasonal variations on IVF pregnancy outcomes: a retrospective cohort study in Jinan, China.Frontiers in medicine · 2025Article
- Summer versus winter: the impact of the seasons on oocyte quality in in vitro fertilization cycles.Revista da Associacao Medica Brasileira (1992) · 2024Article
- Embryo transfers performed during daylight savings time led to reduced live birth rates in older patients.Journal of assisted reproduction and genetics · 2023Observational
- Seasonal fluctuation of in vitro fertilization encounters in the United States.Journal of assisted reproduction and genetics · 2023Article
- Season and temperature do not affect cumulative live birth rate and time to live birth inFrontiers in endocrinology · 2023Article
- Influence of climatic conditions in the mesothermal climate area on pregnancies following elective fresh single blastocyst transfer.Journal of assisted reproduction and genetics · 2022Article
- Effects of seasonal variations and meteorological factors on IVF pregnancy outcomes: a cohort study from Henan Province, China.Reproductive biology and endocrinology : RB&E · 2022Article
- Summer is not associated with higher live birth rates in fresh IVF/ICSI cycles: a population-based nationwide registry study.Human reproduction open · 2022Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 4 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
purposeIt is known that delivery rates from spontaneous conception vary according to season which may be due to cultural or environmental factors; however, conflicting data exist regarding whether outcomes from IVF are also seasonally dependent. The present study was designed to test the hypothesis that the season at oocyte retrieval is associated with livebirth after fresh transfer.
methodsDates of oocyte retrieval for all autologous cycles in our IVF program between January 2012 and December 2017 were categorized by season. Dates were linked to local temperature (min, max, average) and day length obtained from meteorological records. Average maximum temperature and day length were categorized into tertiles. Multivariable logistic regression, adjusted for age and quadratic age, were used to model odds (aOR) of implantation, clinical pregnancy, spontaneous abortion, and livebirth.
resultsPatient characteristics were similar across seasons. As expected, temperature and day length varied by season. When compared with cycles started during winter, there was no difference in the age-adjusted odds of livebirth for the other three seasons (spring: aOR: 0.97, 95% CI: 0.82-1.13; summer: aOR: 1.05, 0.90-1.23; fall: aOR: 0.98, 0.84-1.15). There was a positive linear trend between temperature and odds of implantation, and clinical pregnancy (p value, test for linear trend (implantation, p = 0.02; clinical pregnancy, p = 0.01)) but no association with livebirth for temperature or day length.
conclusionsWe found that season at oocyte retrieval was not associated with livebirth, contrary to patterns seen in naturally conceived populations. However, our data did suggest modestly higher odds of clinical pregnancy for retrievals in June and July, and that higher temperature at time of retrieval was associated with higher odds of clinical pregnancy but not livebirth.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.