JBJuan Balasch

Juan Balasch

*This is an algorithmically generated author record based on publicly available information.

Current Organizations / Institutes

The organizations/institutes from the scholar's latest article

Previous Organizations / Institutes

The organizations / institutes from the scholar's other articles in the past ten years


Juan Balasch has a total of 70 co-authors. Here are the top co-authors by number of shared publications:

  • Francisco Carmona

    Institut Clínic of Gynecology, Obstetrics and Neonatology, Faculty of Medicine - University of Barcelona, Hospital Clínic of Barcelona, Villarroel Street, 170, Barcelona 08036, Spain

    12 shared publications
  • Francisco Fábregues

    Assisted Reproduction Unit Faculty of Medicine University of Barcelona Barcelona Spain

    12 shared publications
  • Montserrat Creus

    Institut Clínic of Gynecology, Obstetrics and Neonatology, Faculty of Medicine - University of Barcelona, Hospital Clínic of Barcelona, Villarroel Street, 170, Barcelona 08036, Spain

    10 shared publications
  • Gemma Casals

    Institut Clínic of Gynecology, Obstetrics and Neonatology, Faculty of Medicine - University of Barcelona, Hospital Clínic of Barcelona, Villarroel Street, 170, Barcelona 08036, Spain

    8 shared publications
  • Juan A. Vanrell

    Institut Clínic of Gynecology, Obstetrics and Neonatology and 1 Institut Clínic of Gynecology, Obstetrics and Neonatology and 2 Hormonal Laboratory, Hospital Clínic-Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain

    8 shared publications
  • Roser Casamitjana

    Hormonal Laboratory, Hospital Clínic-Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Faculty of Medicine-University of Barcelona, Barcelona, Spain

    7 shared publications

Latest Publications

  • Open Access

    Total circulating microparticle levels are increased in patients with deep infiltrating endometriosis

    by J. Munrós, M.A. Martínez-Zamora, D. Tàssies, J.L. Coloma, M.A. Torrente, J.C. Reverter, F. Carmona, J. Balasch

    Are the levels of total circulating cell-derived microparticles (cMPs) and circulating tissue factor-containing microparticles (cMP-TF) increased in patients with endometriosis? The levels of total cMP, but not cMP-TF, were higher in patients with endometriosis, and these were attributed to higher levels in patients with deep infiltrating endometriosis (DIE). Previous studies have reported elevated levels of total cMP in inflammatory conditions as well as higher levels of other inflammatory biomarkers in endometriosis. Increased expression of tissue factor (a transmembrane receptor for Factor VII/VIIa) in eutopic and ectopic endometrium from patients with endometriosis has been described. There is no previous data regarding total cMP and cMP-TF levels in patients with endometriosis. A prospective case–control study including two groups of patients was carried out. The E group included 65 patients with surgically confirmed endometriosis (37 with DIE lesions) and the C group comprises 33 women without surgical findings of any form of endometriosis. Patients and controls were recruited during the same 10-month period. Controls were the next patient without endometriosis undergoing surgery, after including two patients with endometriosis. Venous blood samples for total cMP and cMP-TF determinations were obtained at the time of surgery, before anesthesia at a tertiary care center. To assess total cMP, an ELISA functional assay was used and cMP-TF activity in plasma was measured using an ELISA kit. Total cMP levels in plasma were higher in the E group compared with the C group (P < 0.0001). The subanalysis of endometriosis patients with DIE or with ovarian endometriomas without DIE showed that total cMP levels were higher in the DIE group (P = 0.001). There were no statistically significant differences in cMP-TF levels among the groups analyzed. This is a preliminary study in which the sample size was arbitrarily decided, albeit in keeping with previous studies analyzing cMP in other inflammatory diseases and other biomarkers in endometriosis. The control group included patients with other pathologies as well as healthy controls, and blood samples were taken at different phases of the cycle. Elevated total cMP levels in DIE patients may reflect an inflammatory and/or procoagulant systemic status in these patients. Further studies are warranted to confirm our findings and to assess the role of cMP levels in the pathophysiology of DIE. This study was supported in part by a grant from FIS-PI11/01560 and FIS-PI11/00977 within the ‘Plan Nacional de I + D + I’ and co-funded by the ‘ISCIII-Subdirección General de Evaluación’ and ‘Fondo Europeo de Desarrollo Regional (FEDER)’ and by the grant ‘Premi Fi de Residència Emili Letang 2015’ from the Hospital Clínic of Barcelona. The authors have no competing interests to disclose.


  • Increased circulating cell-derived microparticle count is associated with recurrent implantation failure after IVF and embryo transfer

    by M. Angeles Martínez-Zamora, Dolors Tàssies, Juan Carlos Reverter, Montserrat Creus, Gemma Casals, Salvadora Cívico, Francisco Carmona, Juan Balasch


  • Open Access

    Higher levels of procoagulant microparticles in women with recurrent miscarriage are not associated with antiphospholipid antibodies

    by M.A. Martínez-Zamora, D. Tàssies, M. Creus, J.C. Reverter, B. Puerto, J. Monteagudo, F. Carmona, J. Balasch

    Are the levels of circulating cell-derived microparticles (cMPs) in patients with recurrent miscarriage (RM) associated with the antiphospholipid syndrome (APS)? cMPs in women with RM are not associated with antiphospholipid antibodies (aPLs). Previous studies have focused on cMP levels in RM patients. Most studies have shown higher levels of cMPs in RM patients whereas others have reported lower levels. Data regarding cMPs in patients with the APS are scanty in the literature. A case–control study including three groups of patients. A total of 154 women were prospectively recruited from September 2009 to October 2013. Four patients refused to participate. The APS group consisted of 50 women that had been previously diagnosed with primary APS and had had ≥3 consecutive first trimester miscarriages. The uRM group included 52 couples with ≥3 consecutive first trimester miscarriages of unknown etiology. The fertile control (FER) group was composed of 52 healthy fertile women with no history of pregnancy losses. Miscarriage was defined as intrauterine pregnancy loss at P < 0.0001 and P = 0.009, respectively) (cMP number × 103/ml plasma [mean ± SD]: APS: 18.5 ± 13.6; uRM: 16.3 ± 13.8; FER: 9.7 ± 4.6). There were no statistically significant differences in cMP levels between the APS and uRM groups. The sample size was arbitrarily decided according to previous studies analyzing cMPs in RM patients. Different cMP subtypes were not investigated. The present study adds further data on the subject showing that patients with RM, irrespective of testing positive for aPLs, have increased levels of cMPs compared with healthy fertile controls. The presence of elevated cMPs in RM women may reflect an ongoing systemic pathological, albeit asymptomatic, status that can become deleterious in the setting of pregnancy. This study was supported in part by grant from FIS-PI11/01560 within the ‘Plan Nacional de I+D+I’ and co-funded by the ‘ISCIII-Subdirección General de Evaluación’ and the ‘Fondo Europeo de Desarrollo Regional (FEDER)’. The authors have no competing interests to disclose. Not applicable.


  • Conservative medical treatment of ovarian hyperstimulation syndrome: a single center series and cost analysis study

    by Gemma Casals, Francisco Fábregues, Marco Pavesi, Vicente Arroyo, Juan Balasch

    Objective: To present the results of a large series of patients with ovarian hyperstimulation syndrome treated with a conservative medical approach and to compare the cost of this treatment with outpatient management with paracentesis according to published data.Design: Retrospective case series and cost analysis study using a decision‐tree model.Setting: University hospital.Population: 496 consecutive patients with ovarian hyperstimulation syndrome treated in our center from 1991 to 2010.Methods: All patients were treated with a conservative medical approach: (a) conservative outpatient approach: bed rest and a low‐sodium diet or (b) hospitalized patients: bed rest, low‐sodium diet, 20% albumin (60 g/day) and furosemide (20 mg/8 h).Main outcome measures: Percentage of admissions, length of hospital stay and readmissions. Total cost of each therapeutic approach.Results: (a) Conservative outpatient approach (n = 377): all cases solved without admission. (b) Hospitalized patients with conservative medical treatment (n = 119): 2.8 days of mean hospital stay, no patient required paracentesis or admission to intensive care unit. Readmissions: Five patients (4.2%) resolved on restarting medical treatment. (c) Cost‐analysis comparison: Cost of the outpatient approach with paracentesis: US$980 (range US$519–3557). Cost of conservative medical treatment: US$570 (range US$232–1640).Conclusions: Ovarian hyperstimulation syndrome can be safely managed with a conservative medical approach, which was not found to be more expensive than outpatient management with paracentesis.


  • Outcome from consecutive ICSI cycles in patients treated with recombinant human LH and those supplemented with urinary hCG-based LH activity during controlled ovarian stimulation in the long GnRH-agonist protocol

    by Francisco Fábregues, Montserrat Creus, Gemma Casals, Francisco Carmona, Juan Balasch

    Clinical results were compared in a well-established, assisted reproduction program during the cross-over from highly purified (HP)-human menopausal gonadotropin (hMG) to rhFSH/rhLH. We included the last 33 patients treated with HP-hMG and the first 33 patients receiving rhFSH/rhLH for ovarian stimulation in their first intracytoplasmic sperm injection cycle. Patient baseline characteristics were almost identical in the two groups. Ovarian stimulation characteristics (days of stimulation, total amount of FSH administered using a modest initial loading dose of 150 IU/d, patients with oocyte retrieval) were similar for the two groups. However, the number of total and leading follicles and E2 serum levels on the human chorionic gonadotropin injection day were significantly higher in the rhFSH/rhLH group. The oocyte yield was significantly higher in the rhFSH/rhLH group as well as the number of metaphase II oocytes, difference almost reaching the statistical significance. The number of oocytes fertilized was also higher in patients receiving rhFSH/rhLH treatment. Implantation and clinical pregnancy rates were similar in both the study groups. It is concluded that in women undergoing controlled ovarian hyperstimulation under pituitary suppression for ART, the recombinant combined product containing FSH and LH in a fixed 2:1 ratio is more effective than HP-hMG in terms of follicle development, oocyte yield and quality, and fertilization rates.


  • Open Access

    Plasma homocysteine and vitamin B12 serum levels, red blood cell folate concentrations, C677T methylenetetrahydrofolate reductase gene mutation and risk of recurrent miscarriage: a case-control study in Spain

    by Montserrat Creus, Ramon Deulofeu, Joana Peñarrubia, Francisco Carmona, Juan Balasch

    Hyperhomocysteinemia and methylenetetrahydrofolate reductase (MTHFR) gene mutation have been postulated as a possible cause of recurrent miscarriage (RM). There is a wide variation in the prevalence of MTHFR polymorphisms and homocysteine (Hcy) plasma levels among populations around the world. The present study was undertaken to investigate the possible association between hyperhomocysteinemia and its causative genetic or acquired factors and RM in Catalonia, a Mediterranean region in Spain. Sixty consecutive patients with ≥ 3 unexplained RM and 30 healthy control women having at least one child but no previous miscarriage were included. Plasma Hcy levels, MTHFR gene mutation, red blood cell (RBC) folate and vitamin B12 serum levels were measured in all subjects. No significant differences were observed neither in plasma Hcy levels, RBC folate and vitamin B12 serum levels nor in the prevalence of homozygous and heterozygous MTHFR gene mutation between the two groups studied. In the present study RM is not associated with hyperhomocysteinemia, and/or the MTHFR gene mutation.


  • Open Access

    Human chorionic gonadotrophin stimulation test as a predictor of ovarian response and pregnancy in IVF cycles stimulated with GnRH agonist gonadotrophin treatment: a pilot study

    by Francisco Fábregues, Ainara Iraola, Roser Casamitjana, Francisco Carmona, Juan Balasch

    Recent evidence supports a specific and broad role of androgen produced by theca cells in reproductive physiology. This pilot study evaluated the usefulness of hCG theca stimulation test in predicting ovarian response and pregnancy. Prospective cohort study including 80 infertile women treated with IVF/ICSI. On Day 3 of the menstrual cycle preceding, the first IVF/ICSI cycle a blood sample was drawn to evaluate baseline FSH, estradiol (E2), 17-hydroxy-progesterone, androstenedione and testosterone levels. All women then received 250 µg recombinant hCG s.c. and underwent a second blood sampling 24 h after hCG injection to measurement steroid serum levels. Percentage increment of E2 but not its precursors was significantly higher in normo-responders and pregnancy cycles than in poor responders and non-pregnancy cycles (P = 0.03 and P = 0.02, respectively) diagnostic accuracy being 67 and 75%, respectively. The percentage increase in E2 thus still fails in as many as 33 and 25% of patients in predicting ovarian response and pregnancy, respectively. In addition, E2 concentrations are poorly reproducible and a wide range of variation in all serum steroids investigated—including E2—after hCG injection was observed. The predictive power of the hCG test is based on E2 but not androgen response to hCG injection. This test cannot be recommended in routine clinical practice because it is too laborious for screening purposes, shows great variability in the response obtained and its overall accuracy is not better than that reported for other available markers of ovarian reserve. The use of the currently available markers, antral follicle count and anti-Müllerian hormone, is therefore recommended.


  • Open Access

    Expression pattern of osteopontin and v 3 integrin during the implantation window in infertile patients with early stages of endometriosis

    by Gemma Casals, Jaume Ordi, Montse Creus, Francisco Fábregues, Francisco Carmona, Roser Casamitjana, Juan Balasch

    To study endometrial receptivity in terms of osteopontin (OPN) and αvβ3 integrin expression and co-expression in infertile women with early stages of endometriosis. We investigated the immunohistochemical expression and co-expression of OPN and αvβ3 integrin in the endometrium of 20 infertile patients with Stage I or II endometriosis as the only detectable cause of infertility, 20 infertile patients with unexplained infertility and 20 fertile women undergoing tubal sterilization. Two endometrial biopsies were performed during a single menstrual cycle (postovulatory Day +7 to +8 and 4 days later) in each subject. No statistically significant differences regarding OPN and αvβ3 integrin expression were found between infertile patients with endometriosis and the two control groups. There was no significant correlation between OPN and αvβ3 integrin staining intensity in the mid-luteal phase biopsies in any of the groups studied. Endometrial OPN and αvβ3 integrin expression or co-expression is not impaired during the window of implantation in patients with Stage I–II endometriosis. Further studies are needed to determine whether these results imply normal endometrial receptivity in such patients or add to the increasing uncertainty about the clinical value of assessing the endometrium with these markers of implantation.


  • Reduced plasma fibrinolytic potential in patients with recurrent implantation failure after IVF and embryo transfer

    by M. Angeles Martínez-Zamora, Montserrat Creus, Dolors Tassies, Juan Carlos Reverter, Salvadora Civico, Francisco Carmona, Juan Balasch

    BACKGROUND Recurrent implantation failure (RIF) following embryo transfer (ET) is a major continuing problem in IVF. Women with haemostatic defects may be at increased risk of miscarriage and preclinical pregnancy loss. The fibrinolytic system is considered, at present, the key to new thrombotic pathogenic mechanisms. Patients with unexplained recurrent miscarriage have an impairment of fibrinolysis, as demonstrated by prolonged clot lysis time (CLT) in association with increased plasma levels of thrombin-activatable fibrinolysis inhibitor (TAFI). In this study, we investigated fibrinolytic potential in patients with RIF. METHODS Three groups of patients were studied: 30 women with RIF (RIF group), 60 patients undergoing a first successful IVF–ET cycle (IVF group) and 60 healthy fertile women (FER group). Plasma CLT was measured using a global fibrinolysis assay. TAFI antigen plasma levels and polymorphisms in the TAFI gene (+505A/G and +1542C/G) were analysed using enzyme-linked immunosorbent assay and allele-specific PCR, respectively. RESULTS CLT was significantly longer (P< 0.0001 and P< 0.0009, respectively) and TAFI antigen levels were significantly higher (both P< 0.0001) in the RIF versus the IVF and FER groups. A direct relationship between CLT and TAFI antigen levels (r = 0.40; P = 0.001) was detected in the whole study population. There were no differences in distribution of TAFI polymorphisms between groups. CONCLUSIONS Patients with RIF have reduced plasma fibrinolytic potential, as shown by a prolonged CLT, and this may be explained, at least in part, by increased TAFI antigen levels.


  • Ageing and infertility: an overview

    by Juan Balasch

    In many modern societies, the proportion of women who delay childbearing beyond the age of 35 years has increased greatly in recent decades. They are falsely reassured by popular beliefs that advances in new reproductive technologies can compensate for the age-realted decline in fertility, but science cannot beat the biological clock. Age is the single most important determinant of male and female fertility, either natural or treated. The consequences of advancing maternal age are not only for the risk of natural and assisted conception, but also for the outcome of pregnancy. Female fertility has a ‘best-before date’ of 35, and for men, it is probably before age 45–50.