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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, METHODS, METHODS, METHODS, METHODS, RESULTS. Meshes: Adolescent, Adult, Female, Fertilization in Vitro, Health Status Indicators, Humans, Infertility, Female, Middle Aged, Ovarian Follicle, Ovarian Reserve, Pregnancy, Progesterone, Prognosis, Treatment Outcome, Young Adult.
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Is progesterone-to-follicle index better correlated with in vitro fertilization cycle outcome than blood progesterone level? Context: To investigate the impact of late follicular phase progesterone (P) elevation in relation to ovarian response on cycle outcome. Cohort study. The progesterone-to-follicle index (PFI) was calculated by dividing the blood P by the number of follicles ≥14 mm. The clinical pregnancy rate was calculated against the range of PFI values and blood P levels. In vitro fertilization unit. A heterogenous population undergoing IVF with pituitary suppression and gonadotropin stimulation resulting in 3-15 follicles ≥14 mm and blood P≤10 nmol/L on hCG day and resulting in fresh embryo transfer. None. Association of blood P and PFI with clinical pregnancy rate. Data were retrieved for 8,649 IVF cycles in normal responders. The (reverse) odd ratios for pregnancy were 1.112 (95% confidence interval [CI], 1.077-1.165) for blood P and 4.104 (95% CI, 3.188-5.284) for the PFI. Elevated P levels were associated with a lower pregnancy rate only when they reached the >93rd percentile. The PFI was inversely and linearly related to the pregnancy rate for the whole range of values.
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A late increase in P level is detrimental if it is a consequence of increased P production per follicle (high PFI) but not if it is a consequence of additional follicular recruitment. The PFI enables clinicians to differentiate these conditions. Final Decision: yes