Biomedical subjects

M R Primavera

Publications and source records attributed to M R Primavera.

9 recordsLinked to original sources

PubMed2000

Technical aspects of oocyte cryopreservation.

Since the successful development in the mouse, the oocyte cryopreservation has been applied with varying success to a number of different species including the human. The recently reported successes in terms of pregnancies obtained by human oocyte cryopreservation are encouraging. Several studies typically reported different rates of survival (20-80%), fertilization (30-60%) and cleavage (32-100%). This variability of results throws some doubts on the usefulness of oocyte cryopreservation in IVF treatment cycles. It remains to be determined whether the relatively different success rates reported in literature, mainly in terms of survival rate, are due to methodological differences. We tried to investigate the effect of some factors on the oocyte survival rate after thawing: the presence or absence of cumulus oophorus and the exposure time of the oocytes to cryoprotectant. We suggest that a combination of several factors including both morphological and biophisical ones can affect the oocyte survival rate.

Animals↗

PubMed2000

Perifollicular Doppler flow and follicular fluid vascular endothelial growth factor concentrations in poor responders.

OBJECTIVE: To prospectively evaluate follicular fluid levels of vascular endothelial growth factor in women undergoing IVF cycles and to investigate the correlation of these levels with ovarian response to gonadotropins and with uterine or ovarian Doppler findings. DESIGN: Prospective study. SETTING: University hospital. PATIENT(S): 41 patients undergoing ART were divided into two groups according to response to ovarian stimulation protocols: poor responders (n = 18) and normoresponders (n = 23). INTERVENTION(S): Doppler analysis of perifollicular arteries and assay of follicular fluid vascular endothelial growth factor. MAIN OUTCOME MEASURE(S): During ovarian stimulation, patients underwent hormonal (E2), ultrasonographic (follicular number and diameter, endometrial thickness) and Doppler (uterine and perifollicular arteries) evaluation. Serum and follicular fluid concentrations of vascular endothelial growth factor were assayed in each female patient. RESULT(S): Compared with poor responders, more oocytes were collected and more embryos were transferred but follicular fluid levels of vascular endothelial growth factor levels were lower in normoresponders. Follicular fluid levels of vascular endothelial growth factor were inversely correlated with number of oocytes retrieved. Poor responders had significantly higher uterine and perifollicular Doppler flow resistances. The pregnancy rate per cycle was significantly higher in normoresponders (26%) than poor responders (6%). CONCLUSION(S): Elevated follicular fluid levels of vascular endothelial growth factor concentrations are associated with poor ovarian response and a very low pregnancy rate.

Embryo Transfer↗

PubMed2000

Successful induction of ovulation using highly purified follicle-stimulating hormone in a woman with Kallmann's syndrome.

OBJECTIVE: To describe a woman with Kallmann's syndrome who was treated successfully with highly purified FSH to achieve ovulation induction and pregnancy. DESIGN: Case report. SETTING: University hospital. PATIENT(S): A 32-year-old woman with Kallmann's syndrome who had been treated with oral contraceptives to prime secondary sex characteristics and genital organs since the age of 16 years. INTERVENTION(S): Highly purified FSH was administered intramuscularly for a total dose of 3,825 IU. MAIN OUTCOME MEASURE(S): Follicle number and diameter. RESULT(S): Three follicles with a diameter of > 1.7 cm and an endometrial thickness of 8 mm were observed. A clinical pregnancy, which subsequently was spontaneously aborted, was obtained. CONCLUSION(S): In primed patients with Kallmann's syndrome, highly purified FSH may be a useful alternative to pulsatile GnRH or menopausal gonadotropins to achieve ovulation induction and pregnancy.

Abortion, Spontaneous↗

PubMed2000

Human embryo development and pregnancies in an homologous granulosa cell coculture system.

PURPOSE: Our purpose was to determine the effects of the coculture of embryos on human granulosa cells (GCs) in patients in the first cycle of IVF-ET treatment and in patients with repeated implantation failures and to investigate the presence of specific proteins in a 48-hr GC conditioned medium and the GC ultrastructural characteristics. METHODS: Eighteen patients with tubal or idiopathic infertility were enrolled in this study: 7 patients (Trial 1) were in the first cycle of IVF-ET treatment and 11 patients (Trial 2) had repeated implantation failures (one to five). Embryos from each patient were cocultured randomly either on homologous granulosa cells or on a conventional culture medium. RESULTS: At the end of the coculture period (day 5 or 6), 50% of the embryos (Trial 1) reached the blastocyst stage, with respect to 35% in Trial 2. The pregnancy rate per retrieval was 14.2 and 9%, respectively, in Trial 1 and in Trial 2. Many conditioned media showed proteins of 24-29 kDa. and some of them showed additional proteins of 90 kDa. The ultrastructural analysis of GCs showed healthy, metabolically active, protein-synthesizing, and mostly steroidogenic cells. CONCLUSIONS: GC cultures improve embryo development but not pregnancy rates both in Trial 1 and in Trial 2.

Adult↗

PubMed2000

Allergic reaction to a highly purified urinary follicle stimulating hormone preparation in controlled ovarian hyperstimulation for in vitro fertilization.

We report a case of general hypersensitivity-like allergic reactions to intramuscular injections of highly purified urinary follicle stimulating hormone (uFSH-HP) successfully managed by using intramuscular recombinant FSH (rFSH). The patient underwent a first cycle of in vitro fertilization (IVF) and controlled ovarian hyperstimulation (COH) was achieved with a combination of gonadotropin releasing hormone against (GnRH-a) and uFSH-HP. Because, after oocyte recovery, no fertilization occurred, the couple subsequently entered an intracytoplasmic sperm injection (ICSI) program. During the COH, the woman developed general hypersensitivity-like allergic reactions with itching, redness and swelling. Although there was regular follicular growth, the allergic symptoms worsened and, on day 8 of COH, the stimulation cycle was suspended. A few months later, the patient entered a new ICSI cycle. COH was achieved by using a combination of GnRH-a and rFSH. The cycle was completed and the patient did not report any allergic reaction. To avoid allergic reaction to the protein components of the urine-derived FSH preparations, the use of rFSH is suggested in those patients who present local and/or general hypersensitivity-like allergic reactions.

Adult↗

PubMed1999

Hormonal replacement therapy and urinary problems as evaluated by ultrasound and color Doppler.

OBJECTIVE: To determine how hormone replacement therapy modifies bladder vascularization and urinary symptoms. STUDY DESIGN: Twenty-eight postmenopausal women with urinary symptoms (day-time frequency > 8; nocturia > 1; urgency and/or dysuria) were analyzed before and after 1, 3 and 6 months of hormone replacement therapy. The patients underwent transvaginal ultrasound evaluation of the pelvic organs and endometrial and bladder wall thickness. Transvaginal color Doppler analysis of blood flow impedance of the uterine and intramural bladder wall arteries was performed in all cases. RESULTS: Hormone replacement therapy significantly increased bladder wall and endometrial thickness. This result was associated with significant improvements in uterine and bladder wall vascularization. Urinary symptoms also improved during therapy. CONCLUSION: The study of bladder wall thickness and vascularization provides additional information regarding the beneficial effect of hormone replacement therapy on lower urinary tract symptoms in postmenopausal women.

Aged↗

PubMed1999

Polycystic ovary syndrome: it is always bilateral?

OBJECTIVE: To evaluate whether patients with unilateral polycystic ovary showed different ovarian and uterine blood flow from those with bilateral polycystic ovaries, and to investigate whether there was a correlation between the ultrasonographic aspect and different hormonal parameters. DESIGN: An observational study. SUBJECTS: Sixteen patients with unilateral polycystic ovary and twenty patients with bilateral polycystic ovaries underwent clinical, biochemical, gray-scale and color Doppler ultrasonographic evaluation. METHODS: The following parameters were evaluated: hormonal (luteinizing hormone (LH), follicle stimulating hormone (FSH), LH/FSH concentration ratio, estradiol, prolactin, androstenedione, testosterone), clinical (body mass index, Ferriman-Gallwey score), ultrasonographic (ovarian volume, number and distribution of subcapsular follicles, stromal score) and Doppler (uterine artery and intraparenchymal vessel pulsatility index, ovarian stromal vascularization), in oligomenorrheic patients in the early follicular phase (cycle days 3-5) or in amenorrheic patients at random. RESULTS: Significantly higher androstenedione plasma levels and LH/FSH concentration ratios were observed in bilateral polycystic ovaries. In unilateral polycystic ovaries, gray-scale and color Doppler ultrasonography showed different features in the affected and the unaffected ovary, similar to the appearance of a polycystic and normal ovary, respectively. CONCLUSION: Polycystic ovary syndrome does not predetermine a single ultrasonographic and Doppler pattern.

Adolescent↗

PubMed1999

Uterine and cerebral vascularization in postmenopausal women treated with hormone-replacement therapy.

The effects of hormone-replacement therapy on the Doppler flow parameters of the ophthalmic artery in postmenopausal women were studied and compared with those registered at the level of the internal carotid and uterine arteries. Fifty-seven postmenopausal patients were submitted to continuous estradiol transdermal supplementation and 12-day courses of medroxyprogesterone acetate. During the estrogen phase of hormone-replacement therapy all patients underwent (at 1, 3 and 6 months after the beginning of hormone-replacement therapy) transvaginal ultrasonographic evaluation of the pelvic organs and of endometrial thickness. On the same day, they underwent color Doppler analysis of the blood flow impedance of the uterine, internal carotid and ophthalmic arteries. Estradiol plasma concentrations were assayed on the day that ultrasonographic and Doppler examinations took place. The pulsatility index of all the arteries improved, from baseline values, during the therapy and attained stable values compared to those after the first month of treatment. Furthermore, at the level of the internal carotid and ophthalmic arteries, a significant increase of the peak systolic blood flow velocity (Vmax) was observed over the 6 months of therapy. Doppler studies of the ophthalmic artery are capable of affording specific and precise pathophysiologic information to assess peripheral intracranial blood flow variations. Furthermore, such studies may be useful in monitoring hormone-replacement therapy effects on cerebral perfusion.

Administration, Cutaneous↗

PubMed1998

Oocyte cryopreservation.

Cryopreservation of human oocytes has been employed with little success in clinical practice, even though it may solve the legal and ethical problems linked to embryo freezing. Various attempts to cryopreserve human oocytes have mostly been unsuccessful, leading to low oocyte survival rates after thawing, and the search for an optimal protocol for oocyte cryopreservation remains elusive. A preliminary study was undertaken to evaluate some of the factors influencing the survival rate of human oocytes and the efficiency of intracytoplasmic sperm injection (ICSI) as an insemination procedure. A total of 38 women with tubal infertility were enrolled in the study. The cryopreservation procedure consisted of a slow freeze-rapid thawing technique using 1,2 propanediol and sucrose as cryoprotectants. The overall oocyte survival rate was approximately 60%. A better survival rate was obtained when the oocytes were cryopreserved in the presence of partially removed cumulus oophorus rather than in the presence of totally enzymatically removed cumulus oophorus. The cryoprotectant concentration and the equilibration time also appear to influence the oocyte survival rate. ICSI may be an efficient method of achieving a satisfactory outcome in terms of fertilization in cryopreserved human oocytes. Embryonic morphological quality does not seem to be compromised by cryopreservation. In conclusion, these data show that cryopreservation may ensure that the integrity of the human oocyte is adequate for normal fertilization and embryo development.

Adult↗