Abstract
BACKGROUND: The objective of this study was to assess the trade-off between cycle continuation and cancellation in slow ovarian response (SOR) patients, and to evaluate the impact of SOR on embryo developmental potential and clinical pregnancy outcomes. METHODS: A retrospective analysis was performed on 482 patients with PCOS. Patients were stratified into the SOR group (n = 113) and control group (n = 343) in accordance with follicular growth dynamics. Furthermore, data derived from the cycle cancellation group due to SOR (C-SOR group, n = 18) were incorporated for comparative assessment. Clinical outcomes among the respective groups were subsequently subjected to comparative analysis. RESULTS: The average follicular growth rate in the control group was (1.41 ± 0.45) mm/day, which was significantly higher than that in both the SOR group (1.09 ± 0.55 mm/day, P < 0.05) and the C-SOR group (0.25 ± 0.24 mm/day, P < 0.05). Both SOR and C-SOR groups required significantly more days of Gn and a higher total Gn dose. Notably, supplementation with hCG showed potential for improving ovarian response in patients with SOR. However, if the subsequent follicular growth rate remained below 1.0 mm per day, cycle cancellation was recommended. Although oocytes retrieved was significantly lower in the SOR group than in controls, no intergroup differences were observed in normal fertilization rate, transferable embryo rate, and high-quality embryo rate. Similarly, clinical pregnancy rates after fresh or frozen embryo transfer did not differ between SOR and control groups. However, the SOR group exhibited significantly lower cumulative clinical pregnancy rates (75.22% vs. 88.34%, P < 0.05) and cumulative live birth rates (57.52% vs. 68.8%, P < 0.05) compared with controls. Logistic regression analysis, after adjustment, revealed that the association between SOR and cumulative live birth rates was not statistically significant (adjusted OR = 0.77, 95% CI: 0.47-1.25, p = 0.29). CONCLUSIONS: Assessment of follicular growth rate in patients with SOR may facilitate clinical decision-making regarding continuation of ovarian stimulation or cycle cancellation. PCOS patients with SOR may benefit from hCG supplementation to enhance ovarian reactivity, thereby facilitating cycle completion and promoting the chance of clinical pregnancy.