Objective: To investigate the impact of vaping and smoking on ovarian reserve markers anti-Müllerian hormone (AMH) and follicle-stimulating hormone (FSH). Design: Retrospective observational study. Setting: Users of a private at-home testing service. Population: 21,102 women aged 21-45 not taking hormonal contraception with no preexisting common reproductive health conditions. Methods: Serum AMH and FSH was assayed via finger prick samples and medical history data was collected online. The relationship between vaping or smoking, and log-transformed AMH or FSH was assessed via adjusted multiple linear regression. Logistic regression was used to produce odds ratios for age-dependent low AMH. Main Outcome Measures: Serum AMH (pmol/L), FSH (IU/L) and age-dependent low AMH. Results: Current and occasional vaping significantly decreased AMH by 7.76% (95 CI 12.24-3.05%,p=0.002) and 4.88% (95% CI 8.7-0.9%,p=0.017) respectively. Current vaping increased the odds of low AMH by 1.58 (aOR=1.58,95% CI=1.25-1.99,p<0.001) times, however, FSH was unaffected. Current smoking significantly decreased AMH by 10.1% (95 CI 16.13-7.3%,p=0.002), increasing the odds of low AMH by 1.59 (aOR=1.59,95% CI=1.17-2.12,p=0.002) and significantly increasing FSH by 7.4% (95% CI 4.2-10.63%,p<0.001). Conclusions: Both vaping and smoking have negative impacts on ovarian reserve markers. Funding: This work was supported by Hertility Health Ltd. Keywords: Vaping, e-cigarette, smoking, ovarian reserve, anti-müllerian hormone, follicle stimulating hormone

Objective: Evaluate NHS-funded fertility treatment policies across England, Scotland, and Wales, assessing their alignment with the needs of those trying to conceive and comparing eligibility against NICE guidance. Design: Review of current NHS-funded fertility treatment policies and retrospective analysis of participant data. Setting: Not applicable. Population: Reproductive-age UK-based women using Hertility Health services from 2021-2023, focusing on those actively trying to conceive (TTC) or planning future pregnancies. Methods: Policy evaluation and data review without interventions. Main Outcome Measures: Eligibility for NHS-funded fertility treatment under UK regional policies versus NICE guidance. Results: In total, out of 2980 individuals actively trying to conceive and 6282 individuals planning for future pregnancies, 1700 (57.0%) and 2750 (43.8%) respectively would be ineligible for state-funded treatment under current regional policies: 1551 (57.7%) in England, 123 (53.2%) in Scotland, and 26 (41.9%) in Wales for those actively trying to conceive, and 2558 (43.9%), 146 (41.7%), and 46 (44.2%) for those planning future pregnancies respectively. In contrast, only 248 (8.3%) of those actively trying to conceive and 149 (2.4%) of those planning for future pregnancies would be ineligible if the NICE guidance were universally applied. Conclusions: By imposing outdated clinical and non-clinical qualifying criteria, the current NHS-funded fertility treatment policies exclude a substantial number of individuals requiring treatment. This necessitates a swift policy overhaul, as promised in the 2022 UK Women’s Health Strategy, to avoid further age-related fertility loss in women who require treatment imminently.