THE SPERM ACROSOME REACTION RESPONSE TO PROGESTERONE ASSOCIATED WITH SPERM DNA DAMAGE HAS A BETTER PREDICTING VALUE FOR IVF THAN THAT RESPONSE TO THE IONOPHORE Jianyuan Jin, MS, Yi Zheng, MS, Jiujia Zheng, MS, Xuefeng Huang, MD, PhD Reproductive Medicine Center, The First Affiliated Hospital of Wenzhou Medical University, No. 2 Fuxue Road, Wenzhou 325000, Zhejiang, China RESULTS ABSTRACT The correlation between sperm AR and SDF : Sperm AR response to P4 and A23187 were correlated significantly to the percentage of SDF, with the negative correlation -9.05(-17.25-(-0.84), p<.05, n=47) and -0.453(-0.858-(-0.048), p<.05, n=47), respectively. While the spontaneous AR rate had a positive correlation with SDF (0.182 (0.05-0.314), p<.01, n=129) and a negative correlation with sperm progressive motility (-0.211(-0.362-(-0.061), p<.05, n=129)). Apparently lower induced AR levels were detected in cases with SDF higher than 20% ( Figure. 1). 2. The effect of P4-induced AR on the fertilization rate and its predictive value for IVF, comparing with other parameters: The results of the multivariate linear regressions suggested that P4-induced AR, as well as SDF was significantly correlated to the fertilization rate in IVF(Table 2). And the ROC analyses indicated that P4-induced AR was a better prognostic predictor for the fertilization rate compared with the SDF (Figure 2), with the areas under the curve 0.729 (0.580-0.849), p<.01 and 0.637 (0.484-0.772), p=.16, respectively. A cutoff value for P4-induced AR to predict “50% fertilization rate” was 23.4% with sensitivity and specificity of 63.3% and 88.2%, respectively. When the percentage of P4-induced AR<23.4%, the adjusted β (95% CI) was 0.135 (0.014-0.257, P<.05) (Table 2). The correlation between spontaneous, A23187-induced AR and fertilization rate were not significant. Sperm acrosome reaction (AR), a highly Ca2+ influx dependent event, is essential for the fertilizing ability. Progesterone(P4) have been widely known as a physiological stimulator of sperm AR. In recent years, along with the importance of the CatSper calcium channel (a major receptor of P4 in human sperm) being identified and well elaborated, the interaction between the fertilizing spermatozoon and P4 triggered AR activity probably should be further elucidated. Another question we concerned is that whether the alteration of sperm DNA integrity reflects an overall impairment of sperm function, including the motility, capacitation and especially the following AR. OBJECTIVES Figure 1 Figure 2 Table 1. Baseline characteristics of all cases, and the parameters comparison between the >50% or ≤50% fertilization rate group. To evidence the correlation between P4-induced AR and sperm DNA fragmentation (SDF) and to determine the predictive value of P4-induced AR for in vitro fertilization (IVF). Parameters All IVF cases (n=129) >50% fertilization rate (n=91 ) ≤50% fertilization rate (n=38 ) Female age (year) 31.1±3.6(24.0-38.0) 30.9±3.5 31.5±3.8 Retrieved oocytes 13.0±5.9(4.0-27) 12.8±5.6 13.2±6.7 Male age (year) 32.2±4.1(25.0-45.0) 31.8±3.8 33.1±4.6 Sperm concentration(×106) 59.8±30.5(9-178) 61.8±31.7 55.1±27.3 Progressive motility (%) 50.7±10.7(23-77) 51.4±10.9 49.1±10.2 Normal sperm morphology (%)a 4.8±3.4(0-15.7) 5.3±3.2 3.5±3.4** SDF (%) 16.5±11.4(2.5-71.7) 15.6±11.7 18.6±10.6 Fertilization rate (%) 63.9±21.4(0.0-100.0) 75.1±12.4 37.2±13.0** Spontaneous AR rate (%) 10.8±8.8(1.8-54.3) 10.3±7.6 11.8±11.1   (n=47) (n=30) (n=17) P4-induced AR (%) 20.5±12.9(0-45.6) 24.1±12.9 14.1±10.5** A23187-induced AR (%) 27.1±13.8(0.5-56.5) 28.9±15.4 24.0±10.0 a with the WHO criteria (2010) ** represent significant difference when the value compared to the group of >50% fertilization rate, P ≤0.01. METHODS Design: The spontaneous or induced (response to P4 or A23187) sperm AR were assessed in 129 patients including a subgroup of 47 who underwent IVF treatment (the female paternal with or without simple tubal factors and the male patient with a semen concentration ≥10×106/ml and sperm progressive motility ≥20%). Methods: Conventional semen analysis was performed using CASA system or according to the WHO laboratory manual. Sperm AR was evaluated by using fluorescein-conjugated Pisum sativum agglutinin (FITC-PSA). SDF was analyzed by the Sperm Chromatin Structure Assay (SCSA). The multivariate linear regressions were performed to detect the correlations between P4-induced AR and sperm motility, normal morphology, SDF and the fertilization rate of IVF. Receiver operating characteristic (ROC) curve analysis was used to determine the prognostic accuracy of P4-induced AR as well as the cutoff point for predicting “50% fertilization rate”. And with the univariate and multivariate linear regressions analysis, the adjusted β value and 95% CI was calculated to present the effect of the threshold value. Statistically significant difference was set at p<.05. CONCLUSIONS Table 2. Results of univariate and multivariate linear regression analyses aiming to investigate the associations with spontaneous or induced AR for fertilization rate in IVF (n=47). Induced sperm AR is negatively correlated with sperm DNA damage, further direct evidence need to be provided for interpreting the relationship. The assessment of P4-induced AR of capacitated sperm may be a more sensitive indicator for fertilization rate in vitro compared with A23187-induced AR.. Clinical outcome: fertilization rate (%) Variable Reference Adjust β(95%CI) Confounders adjusted Spontaneous AR (%) <15 -0.100(-0.258-0.059) Male age, Sperm progressive motility, normal morphology, SDF A23187-induced AR (%) <30.3 0.095(-0.039-0.230) P4-induced AR (%) <23.4 0.135(0.014-0.257)* SDF (%) <19.4 -0.154(-0.299-(-0.008))* Male age, Sperm progressive motility, normal morphology Normal sperm morphology (%) <3.9 0.096(-0.032-0.224) Male age, Sperm progressive motility, SDF Confounders were the variables that were found to be significantly correlated with clinical outcomes in univariate models. * represent significant effect associated with outcome compared to the corresponding reference, P<0.05. REFERENCES Baldi E, Luconi M, Krausz C, Forti G. Progesterone and spermatozoa: a long-lasting liaison comes to definition. Hum Reprod 2011; 26, 2933-2934. Tamburrino L, Marchiani S, Minetti F, Forti G, Muratori M, Baldi E. The CatSper calcium channel in human sperm: relation with motility and involvement in progesterone-induced acrosome reaction. Hum Reprod 2014; 29, 418-428. …… Printed by