Cristina González-Ravina

Prof. Dr. Cristina González-Ravina


Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
30 May 2022 in Cells
Verified
Journal Article
Open access
PDF file
CGCristina González-Ravina
Cristina González-Ravina
ESEsther Santamaría-López
Esther Santamaría-López
APAlberto Pacheco
Alberto Pacheco
JRJulia Ramos
Julia Ramos
FCFrancisco Carranza
Francisco Carranza
MFManuel Fernández-Sánchez
Manuel Fernández-Sánchez
Clinical outcome in assisted reproduction techniques (ARTs) is mainly influenced by the quality of gametes used. It is known that a high percentage of sperm DNA fragmentation (DNAf) decreases the success of ART clinical results. Therefore, techniques such as magnetic-activated cell sorting (MACS) help to improve results in cases of patients with a high percentage of DNAf. Cryopreservation of sperm in donor intrauterine insemination (D-IUI) treatments increases sperm DNAf, so patients using these sperm samples can benefit from using this technique. This prospective randomized national multicenter study analyzed clinical outcomes of 181 D-IUI treatments. MACS was performed after density gradient centrifugation (DGC) in 90 thawed semen donor samples (MACSG), whereas only DGC was performed in 91 thawed semen donor samples (CG). To our knowledge, this is the first study analyzing the effect of MACS on D-IUI cycles. Our results show no significant differences in gestation, live birth, or miscarriage rates between the two groups. We believe that further studies with a larger sample size are needed to evaluate the application of MACS in combination with standard IUI donor sperm preparations in fertility clinics.

12 May 2021 in Biology
Verified
Journal Article
Open access
PDF file
MJMaría Gil Juliá
María Gil Juliá
IHIrene Hervas
Irene Hervas
AGAna Navarro Gómez-Lechón
Ana Navarro Gómez-Lechón
FQFernando Quintana
Fernando Quintana
DPdavid amorós prats
david amorós prats
NGNicolás Garrido
Nicolás Garrido
The application of MACS non-apoptotic sperm selection in infertility clinics is controversial since the published literature does not agree on its effect on reproductive outcomes. Therefore, it is not part of the routine clinical practice. Classical measures of reproductive success (pregnancy or live birth rates per ovarian stimulation) introduce a bias in the evaluation of a technique’s effect, since only the best embryo is transferred. This retrospective, multicenter, observational study evaluated the impact of MACS on reproductive outcomes, measuring results in classical parameters and cumulative live birth rates (CLBR). Data from ICSI cycles using autologous oocyte in Spanish IVIRMA fertility clinics from January 2008 to February 2020 were divided into two groups according to their semen processing: standard practice (reference: 46,807 patients) versus an added MACS sperm selection (1779 patients). Only when measured as CLBR per embryo transferred and per MII oocyte used was the difference between groups statistically significant. There were no significant differences between MACS and reference groups on pregnancy and live birth rates. In conclusion, results suggest that non-apoptotic sperm selection by MACS on unselected males prior to ICSI with autologous oocytes has limited clinical impact, showing a subtle increase in CLBR per embryo transferred.

15 September 2021 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
JRJulia Ramos
Julia Ramos
CCCinzia Caligara
Cinzia Caligara
ESEsther Santamaría-López
Esther Santamaría-López
CGCristina González-Ravina
Cristina González-Ravina
NPNicolás Prados
Nicolás Prados
MFManuel Fernández-Sánchez
Manuel Fernández-Sánchez
Introduction: Simplified ultrasound-based infertility protocols that appear to provide enough information to plan effective management have been described. Thus, the objective of this study is to compare the diagnostic accuracy of the hysterosalpingo-foam sonography (HyFoSy) in tubal patency testing with the traditional hysterosalpngography (HSG) for establishing a new diagnostic strategy in infertility. Material and Methods: Prospective observational diagnostic accuracy was performed in a private fertility clinic in which 106 women undergoing a preconceptionally visit were recruited. All of them had low risk for tubal disease, had performed an HSG and were negative for Chlamydia trachomatis antibody. Main outcome measures were tubal patency and pain grade. Results: Evaluation of tubal patency by HyFoSy showed a total concordance with the results of the previous HSG in 72.6% (n = 77), and a total discordance for 4.7% (n = 6), with the inter-test agreement Kappa equal to 0.57, which means moderate concordance. Among the patients, 59.1% did not report pain during the procedure, while the remaining 48.1% indicated pain in different degrees; patients usually report less pain and only 6.6% described more pain with HyFoSy than with HSG (OR 6.57 (CI 95% 3.11–13.89)). Clinical outcomes after performing HyFoSy were not affected. Conclusions: HyFoSy is in concordance with HSG regarding tubal patency results and it is a less painful technique than HSG. HyFoSy is more economical and can be performed in an exam room only equipped with an ultrasound scanner. Based on these results, HyFoSy could be the first-choice diagnostic option to assess tubal patency in patients with low risk of tubal disease.

31 December 2019 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
VBVíctor Blasco
Víctor Blasco
FPFrancisco Pinto
Francisco Pinto
CGCristina González-Ravina
Cristina González-Ravina
ESEsther Santamaría-López
Esther Santamaría-López
LCLuz Candenas
Luz Candenas
MFManuel Fernández-Sánchez
Manuel Fernández-Sánchez
Infertility is a global disease affecting one out of six couples of reproductive age in the world, with a male factor involved in half the cases. There is still much to know about the regulation of human male fertility and thus we decided to focus on two peptide families that seem to play a key role in this function: tachykinins and kisspeptins. With this aim, we conducted an exhaustive review in order to describe the role of tachykinins and kisspeptins in human fertility and their possible implications in infertility etiopathogenesis. Many advances have been made to elucidate the roles of these two families in infertility, and multiple animal species have been studied, including humans. All of this knowledge could lead to new advances in male infertility diagnosis and treatment, but further research is needed to clarify all the implications of tachykinins and kisspeptins in fertility.

Verified
Journal Article
Open access
PDF file
AOAna Ortiz-Vallecillo
Ana Ortiz-Vallecillo
ESEsther Santamaría-López
Esther Santamaría-López
DRDiego García Ruiz
Diego García Ruiz
DMDavid Martín
David Martín
LCLuz Candenas
Luz Candenas
CGCristina González-Ravina
Cristina González-Ravina
Capacitation involves tyrosine phosphorylation (TP) as a key marker. Lifestyle-related factors, such as obesity and smoking, are recognized for their adverse effects on semen quality and male fertility, yet the underlying mechanisms, including their potential impact on TP, remain unclear. Moreover, the effect of sperm cryopreservation on TP at the human sperm population level is unexplored. Flow cytometry analysis of global TP was performed on pre-capacitated, post-capacitated and 1- and 3-hours’ incubated fresh and frozen–thawed samples from sperm donors (n = 40). Neither being overweight nor smoking (or both) significantly affected the percentage of sperm showing TP. However, elevated BMI and smoking intensity correlated with heightened basal TP levels (r = 0.226, p = 0.003) and heightened increase in TP after 3 h of incubation (r = 0.185, p = 0.017), respectively. Cryopreservation resulted in increased global TP levels after capacitation but not immediately after thawing. Nonetheless, most donors’ thawed samples showed increased TP levels before and after capacitation as well as after incubation. Additionally, phosphorylation patterns in fresh and frozen–thawed samples were similar, indicating consistent sample response to capacitation stimuli despite differences in TP levels. Overall, this study sheds light on the potential impacts of lifestyle factors and cryopreservation on the dynamics of global TP levels during capacitation.