Climate change is intensifying both chronic and acute heat stress. Literature suggests that heat stress adversely affects pregnancy. Evidence on seasonal variations in IVF outcomes remains limited and inconclusive. To date, no studies have evaluated direct effect of ambient temperature on IVF outcomes. We conducted cross-sectional study in 690 patients who underwent IVF in Andhra Pradesh, India. Time-stamped clinical data and meteorological data (2019-2023) were acquired. We used Poisson and logistic regression to model IVF outcomes with respect to time- lagged heat stress exposure, adjusted for potential confounders. When a week-lagged temperature was ≥30° C, a unit increase in weekly average temperature was associated with an 8% less number of oocytes (IRR = 0.92; 95% CI = 0.92 – 0.98; p < 0.01). An increase in 1 SD of hourly temperature in one week-lag temperature was associated with 36% decrease in number of oocytes retrieved (IRR= 0.64; 95% CI = 0.51 – 0.81; p < 0.01). A similar trend was noted for good quality oocytes. Both high (> 30°C) and low (< 25°C) temperatures were inversely associated with biochemical and clinical pregnancy confirmation. When temperature was ≥ 30° C, 1 week prior to embryo transfer, a unit increase in ambient temperature was significantly associated with 39% lower odds of pregnancy confirmation (OR = 0.61; 95% CI = 0.43 – 0.88; p < 0.01). With 1 SD increase in a week-lagged temperature, odds of pregnancy confirmation decreased by 71% (OR= 0.29; 95% CI = 0.13 – 0.65; p < 0.01. A 10° F increase in two-day lag heat stress was associated with 3% higher odds of missed abortion (OR = 1.03; 95% CI = 1.001-1.068; p-value < 0.043). Our results demonstrated significant association between ambient temperature and IVF outcomes, underscoring urgent need for further research to develop guidelines that integrate climate resilience strategies into fertility care

Venkata Madhavi Latha Telagarapu is a physician, surgeon, and public health professional with 20 years of experience in clinical care, healthcare leadership, and clinical research. She earned her medical degree and specialist qualification in Obstetrics and Gynecology followed by an MBA in Hospital Administration, in India, and Master of Public Health at the University of Miami, graduating summa cum laude. Her career spans comprehensive clinical practice in high-risk pregnancies, infertility, IVF treatment, and OBGYN radiology, complemented by strong research contributions in reproductive health. She has authored peer-reviewed publications, contributed book chapters, and served as peer reviewer for academic journals. She presented her research at national and international conferences in USA, including her groundbreaking work on effects of heat stress on IVF treatment outcomes. She also collaborates with researchers at the University of Houston on endometrial cancer study, exploring innovative approaches to women’s health. Dr. Telagarapu’s commitment to advancing evidence-based medicine has been recognized with first-prize award for research presentation at ESRF 2024 conference. She has also led health education initiatives focused on women and children, health. Her professional journey reflects a lifelong dedication to advancing women’s health and public health through clinical excellence, research innovation, and public health education