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Pedro N Barri

Publications and source records attributed to Pedro N Barri.

11 recordsLinked to original sources
PubMed2006

Effect of using an echogenic catheter for ultrasound-guided embryo transfer in an IVF programme: a prospective, randomized, controlled study.

BACKGROUND: Recent evidence showed that ultrasound-guided embryo transfer significantly increases successful implantation compared to the clinical touch method. It has been postulated that new echodense catheters which are more readily detectable by ultrasound may refine transfer techniques even more, thus improving IVF outcome. METHODS: A prospective, randomized, controlled trial comparing IVF outcome for women undergoing embryo transfer under ultrasound guidance by a single healthcare provider with random assignment according to a computer-generated randomization table to either standard soft Wallace catheter (standard catheter group, n=95) or the new echogenic soft Wallace catheter (echogenic catheter group, n=98). RESULTS: The use of the echodense catheter facilitated catheter identification under ultrasound, and thus the duration of the embryo transfer procedure since the loaded catheter was handed to the physician and up to embryo discharge was significantly shorter in the echogenic catheter group as compared with the standard catheter group. There were 39 and 53 clinical pregnancies in the standard catheter (41%) and echogenic catheter (54.1%) groups, respectively. This was not statistically significant (P=0.08) according to the OR (0.6) and CIs (0.33-1.04). However, twin pregnancy rate was significantly increased (P<0.01) with the use of the new catheter which was the underlying source for obtaining significant increase in implantation rate in this group (37.1%) as compared with the standard catheter group (23.2%). CONCLUSION: This pilot study suggests that the use of the echogenic Wallace catheter simplifies ultrasound-guided embryo transfer but not definite benefit in terms of pregnancy rates was obtained. In contrast, the use of the new catheter was associated with a significant increase in the number of twin pregnancies.

Adult↗
PubMed2006

Clinical strategies to avoid multiple pregnancies in assisted reproduction.

Multiple pregnancies following assisted reproductive techniques (ART) became an epidemic in the early nineties. Since then, most European countries have tried to apply restrictive policies to avoid multiples and high order multiples as far as possible. Those pregnancies may cause severe consequences to both the fetuses and mother. Economic, social and ethical dilemmas are also avoidable if caution is exercised when using ART to achieve those pregnancies. When restrictive policies are used in ovulation induction and in vitro fertilization, the results show a clear reduction in the number of MP maintaining satisfactory rates.

Female↗
PubMed2005

Use of a prediction model for high-order multiple implantation after ovarian stimulation with gonadotropins.

OBJECTIVE: To determine prospectively the effectiveness in clinical practice of a prediction model for high-order multiple pregnancies (HOMP) (triplets or more). DESIGN: Prospective study. SETTING: University teaching hospital. PATIENT(S): Eight hundred forty-nine consecutive infertile patients undergoing a total of 1,542 treatment cycles. INTERVENTION(S): Gonadotropin ovarian stimulation or induction of ovulation without IVF MAIN OUTCOME MEASURE(S): Observed and predicted overall pregnancy rates and the incidence of HOMP. RESULT(S): The use of the prediction model (implying cancellation of all cycles at high risk for HOMP) would result in an 8% (95% confidence interval, 6.8%-9.2%) reduction of overall pregnancy rate but also in a 285% (95% CI, 279%-291%) reduction of HOMP. CONCLUSION(S): By using our prediction model, it was possible to maintain a low risk of HOMP with a good pregnancy rate in patients receiving gonadotropin ovarian stimulation or induction of ovulation without IVF.

Adult↗
PubMed2005

Influence of spermatogenic profile and meiotic abnormalities on reproductive outcome of infertile patients.

Genetic aspects of male infertility and the possible risks of new assisted reproduction and their influence on the development of zygotes and children born after intracytoplasmic sperm injection (ICSI) need further research. These patients have an increased risk of diploidy, and disomies are frequent in their spermatozoa. Meiotic disorders are more common in testicular biopsies of patients with severe oligoasthenozoospermia. For these reasons, a detailed andrological study is absolutely mandatory before accepting a couple with these characteristics into an IVF-ICSI programme. When an andrological patient has plasma FSH values >10 IU/l and/or very low total motile sperm count <1 x 10(6), despite a normal karyotype, they clearly need a testicular biopsy and a meiotic study in order to rule out meiotic arrest or synaptic anomalies. Another important aspect to be considered is the possible benefit of applying preimplantation genetic diagnosis in these cases because they normally have a high percentage of chromosomally abnormal embryos, although in the present study this was not evident. All studies agree on the necessity of conducting follow-up studies in the population of children born after IVF-ICSI. In this way, it will be possible to find out if these infertile patients and their offspring have a higher risk of suffering epigenetic errors and imprinting disorders.

Case-Control Studies↗
PubMed2004

Serum progesterone concentrations on the day of HCG administration cannot predict pregnancy in assisted reproduction cycles.

The effect of subtle rises of progesterone in the late follicular phase of cycles of ovarian stimulation with gonadotrophin-releasing hormone (GnRH) agonists on pregnancy outcome is controversial. This study used receiver-operating characteristic (ROC) analysis to gain further insight into the predictive value of serum progesterone concentrations on the day of human chorionic gonadotrophin (HCG) injection in normally responding patients receiving the long protocol of GnRH agonist (group L; n = 218) and in low responders receiving the short ('flare-up') protocol (group S; n = 159). ROC analysis showed that serum progesterone concentration on the HCG day was not indicative of conception and non-conception cycles in the whole population studied, in group L or in group S. To further assess the potential impact of 'high' concentrations of circulating progesterone on the day of HCG administration on pregnancy rates and outcome, the threshold value (<0.9 ng/ml) to discriminate between women with 'high' (group H; n = 197) and 'normal' (group N; n = 180) progesterone was applied. No significant differences were found with respect to pregnancy and miscarriage rates between these two groups. Serum progesterone concentrations on the day of HCG administration therefore cannot predict pregnancy in assisted reproduction cycles using GnRH agonists and gonadotrophins.

Adult↗
PubMed2003

Cost-effectiveness of recombinant versus urinary follicle-stimulating hormone in assisted reproduction techniques in the Spanish public health care system.

PURPOSE: To evaluate the relative cost-effectiveness of recombinant and urinary follicle-stimulating hormone (FSH) in assisted reproduction techniques in the Spanish National Health Service. METHODS: Markov modelling was used to compare costs and outcomes of three complete treatment cycles using recombinant or urinary FSH for controlled ovarian stimulation. Cost and effectiveness estimates were obtained from the literature and from Spanish clinicians. A Monte Carlo technique was used to randomise the distribution of outcomes at each stage. The analysis was performed by passing a virtual population of 100,000 patients through the computer simulation in each of 5000 Monte Carlo simulations. RESULTS: The cost per pregnancy was Euro12,791+/-1202 ($11,346+/-1066) with recombinant and Euro13,007+/-1319 ($11,537+/-1170) with urinary FSH (p < 0.0001). The mean number of cycles per pregnancy was 4.69 and 5.21, respectively. CONCLUSIONS: Recombinant FSH is more cost-effective than urinary FSH in the Spanish public health care system.

Female↗
PubMed2002

The role of GnRH antagonists in assisted reproduction.

The different schemes of application of gonadotrophin-releasing hormone (GnRH) antagonists in ovarian stimulation protocols for assisted reproduction are reviewed. Starting from the initial schemes of single and/or multiple doses, the efficacy of GnRH antagonists in 'soft' protocols of ovarian stimulation has been evaluated in natural cycles, and the possibility of inducing the final oocyte maturation under antagonists either with native luteinizing hormone-releasing hormone or with GnRH agonists. The largest clinical studies carried out with cetrorelix or with ganirelix and published to date were analysed. Apart from the benefits of reducing the duration of the treatment, gonadotrophin requirements and ovarian hyperstimulation syndrome incidence, there is still a serious debate on the potential deleterious effect of GnRH antagonists on implantation and pregnancy rates. More specific aspects such as cycle programming, application of GnRH antagonists in protocols for poor responders etc., were also reviewed in this survey.

Buserelin↗
PubMed2002

The usefulness of ultrasound guidance in frozen-thawed embryo transfer: a prospective randomized clinical trial.

BACKGROUND: Recent randomized controlled trials have shown that implantation and pregnancy rates were improved with ultrasound-guided embryo transfer compared with clinical touch in fresh IVF cycles associated with supraphysiological ovarian steroid levels. However, the usefulness of ultrasound guidance in frozen-thawed embryo transfer where potential hormonal influences are lacking has not been appropriately investigated. METHODS: A total of 184 consecutive patients undergoing thawed embryo transfer cycles with hormone replacement under pituitary suppression were randomized by computer-generated randomization table to two study groups: 93 had ultrasound-guided (group 1) and 91 had clinical touch (group 2) embryo transfer. RESULTS: There was equal distribution between the two study groups with respect to the main demographic and baseline characteristics of the patients as well as the characteristics of both prior IVF cycles from which embryos were generated and cryopreserved-thawed embryo transfer cycles. However, both pregnancy and implantation rates in group 1 (34.4 and 19.8% respectively) were significantly higher than the corresponding values (19.7 and 11.9%) in group 2. CONCLUSIONS: Ultrasound guidance in frozen-thawed embryo transfer significantly increases pregnancy and implantation rates.

Adult↗
PubMed2002

The influence of the depth of embryo replacement into the uterine cavity on implantation rates after IVF: a controlled, ultrasound-guided study.

BACKGROUND: Traditionally, embryo transfer after IVF has been performed blindly and placing the embryos approximately 1 cm below the fundal endometrial surface. However, it has been suggested that transferring embryos rather lower in the uterine cavity or high in the uterus may improve implantation rates. Nevertheless, there has not yet been a controlled trial to prove this theory. This prospective randomized study investigates the influence of the depth of embryo replacement on the implantation rate after embryo transfer carried out under transabdominal ultrasound guidance. METHODS: A total of 180 consecutive patients undergoing ultrasound-guided embryo transfer were randomized to three study groups according to the distance between the tip of the catheter and the uterine fundus at the moment of the embryo deposition in the lumen of the endometrial cavity: group 1: 10 +/- 1.5 mm; group 2: 15 +/- 1.5 mm; group 3: 20 +/- 1.5 mm. RESULTS: There was equal distribution between all three study groups regarding the main demographic and baseline characteristics of the patients, ovarian response, oocyte retrieval and IVF outcome, as well as the characteristics of embryo transfer and luteal phase support. The position of the catheter tip in relation to the fundal endometrial surface in groups 1 (10.2 +/- 0.9 mm), 2 (14.6 +/- 0.7 mm) and 3 (19.3 +/- 0.8 mm) was significantly different. Implantation rate was significantly higher (P < 0.05) in groups 2 (31.3%) and 3 (33.3%) compared with group 1 (20.6%). CONCLUSIONS: The depth of the embryo replacement into the uterine cavity may influence implantation rates, and thus it should be considered as an additional procedure among factors recently proposed as associated with successful embryo transfer after IVF.

Adult↗