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Biomedical subjects

P Drakakis

Publications and source records attributed to P Drakakis.

28 records · Page 2Linked to original sources
PubMed1998

The effect of the duration of GnRH-agonist down regulation before ovarian stimulation on the biological and clinical outcome after intracytoplasmic sperm injection.

The object of this study was to compare the biological outcome (oocyte maturity, fertilization, cleavage) and the clinical outcome after a 'long' (15-24 days) and a 'long-long' (25-40 days) protocol of GnRH-agonist administration for intracytoplasmic sperm injection. Group A consisted of 51 patients with a 15-24-day down regulation period and Group B consisted of 35 patients with a 25-40-day down regulation period, all of which entered ICSI due to severe male factor infertility. Duration and amount of gonadotropin stimulation, serum E2 on the day of hCG administration, number of oocytes retrieved, oocyte maturity, fertilization rate, cleavage rate and pregnancy outcome were comparable for the two groups of patients. Therefore, a flexible period of pituitary desensitization can be employed, allowing us to simplify planning for patients and for the medical staff without affecting the outcome of the trial.

Adult↗
PubMed1998

Colpopexy: a modification of Shaw's technique.

The efficacy of colpopexy using an autograft is assessed. The method was used in patients with post-hysterectomy vaginal vault prolapse and/or suffering from uterine prolapse complicated by ovarian pathology. Thirty-five patients were subjected to a modified operative procedure based on Shaw's original method and completed with a posterior colporrhaphy. All patients are now free of urinary and/or pelvic symptoms with a functional vagina, after a 48 to 60 months post-operative follow-up. Pelvic cellulitis was observed in two patients and low abdominal pain in three others for a period of 1 month.

Journal Article↗
PubMed1996

The in vitro development of mouse embryos beyond the blastocyst stage into the hatching and outgrowth stage using different energy sources.

PURPOSE: The purpose of this study was to investigate the effect of male and female serum supplementation on the in vitro development of mouse embryos beyond the blastocyst stage until the outgrowth stage since the latter may be related to the nidation of the embryo. We also studied the effect of EGF addition on embryo culture and blastocyst outgrowth. METHODS AND RESULTS: The blastocyst and hatching rates of two-cell mouse embryos cultured in Ham's F-10 + BSA, Ham's F-10 + male serum, or Ham's F-10 + female serum were found to be comparable (P > 0.05). The outgrowth rate of hatched blastocysts was significantly increased, though, when they were transferred to 50% male serum compared to either 50% BSA or 50% female serum (P < 0.01 and P < 0.05, respectively). In the last experiment, either 100 or 150 ng/ml EGF was added to the culture medium from the two-cell stage till blastocyst development and the latter were cultured till outgrowth in 50% BSA, male serum, or female serum. For both concentrations of EGF, the outgrowth rate was significantly higher in male serum compared to the other conditions (P < 0.01 and P < 0.05, respectively). The outgrowth rate was also higher when EGF was used compared to plain medium before transferring the blastocysts to either male or female serum (P < 0.01 for both). CONCLUSIONS: We conclude that the development of embryos to the outgrowth stage is significantly enhanced by male serum. The addition of EGF from the two-cell stage also significantly improves the outgrowth success rate for both male and female serum conditions.

Animals↗
PubMed1996

Oocyte donation to women over 40 years of age: pregnancy complications.

Recently, oocyte donation to women of advanced age has led to a considerable number of conceptions, thus increasing the age limit for becoming pregnant. A main consideration encountered by physicians, though, is the potential medical and obstetric complications of a pregnancy at an advanced age. In this study, the obstetric complications, as well as the perinatal outcome, of pregnancies of aged recipients (above 40) are presented and compared to those of younger recipients. A significantly higher incidence of gestational diabetes (P < 0.001), an increased incidence of pre-eclampsia (at the 10% level of significance) and an increased risk for thrombophlebitis (again at the 10% level) was observed in the older patients, but a careful follow-up during their pregnancy led to a highly satisfactory obstetric and perinatal outcome. A rigorous precycle medical screening (especially for cardiovascular diseases and diabetes) and a careful follow-up during pregnancy is, therefore, imperative so that oocyte donation to older women is not withheld and continues to provide fertility possibilities to otherwise sterile patients.

Adult↗
PubMed1996

A flexible protocol for the induction of recipient endometrial cycles in an oocyte donation programme.

Synchronization of the availability of good quality oocytes from donors and adequate endometrial maturation of recipients are very important for the success of an oocyte donation programme. A flexible protocol for the endometrial preparation of recipients is important in timing embryo transfer between days 17 and 19 of the cycle ('window of receptivity'). The purpose of this study was to evaluate the effect of the length of oestradiol administration to recipients on pregnancy outcome. Oestrogen administration was 8 mg/day, but its length varied prospectively from 6 to 27 days, followed by the addition of progesterone (100 mg daily i.m.) for 2-4 days according to the availability of good quality oocytes. Pregnancy outcome was evaluated regardless of age, indication for oocyte donation or number of embryos transferred per patient. The pregnancy rate per cycle was comparable when oestradiol was administered from 6 to 11 days before progesterone addition, while it dropped significantly thereafter. The variation in progesterone administration did not affect pregnancy outcome. These findings provide us with a greater flexibility by allowing us to vary oestradiol administration to recipients from 6 to 11 days prior to progesterone, reducing considerably, therefore, the need to cancel embryo transfer because of oocyte unavailability. Thus we can arrange to transfer embryos between days 17 and 19 of the recipient's cycle so as to obtain the best possible clinical outcome.

Adult↗
PubMed1995

Uterine pinopodes as markers of the 'nidation window' in cycling women receiving exogenous oestradiol and progesterone.

In 14 cycling women participating in an in-vitro fertilization (IVF) donation programme, we examined the timing of the 'nidation window' using as a stage-specific 'marker' the presence of fully developed pinopodes on the apical surface of the luminal uterine epithelium. Each woman received exogenous oestradiol from the second day of their cycle and progesterone starting on day 8 or day 15 of the oestrogenic treatment. The women underwent two biopsies during the same artificial cycle, on either days 6 and 9 or days 8 and 10 of the progesterone treatment. All patients to whom oestradiol was administered for 7 days prior to progesterone administration (n = 9), and two of the five treated with oestradiol for 14 days prior to the addition of progesterone, showed uterine pinopodes in either one or both biopsies. When present on a given day, pinopodes were at the same stage, developing, fully developed or regressing, showing that their total lifespan did not exceed 48 h. Fully developed pinopodes existed for 1 day only which may correspond to the short period of optimal endometrial receptivity observed in animal models. The timing of the presence of fully developed pinopodes varied from patient to patient, but these individual differences were not correlated with progesterone and oestradiol plasma concentrations. The brief duration of the nidation window and the observed individual variations in its timing suggest that the detection of uterine pinopodes could be a valuable tool for the prediction, on an individual basis, of the optimal date for successful egg replacement in IVF patients.

Adult↗
PubMed1995

A preliminary study of the effect of growth hormone on mouse preimplantation embryo development in vitro.

The role of growth hormone (GH) in follicular development, ovulation and embryo development is currently under reconsideration. In this study, we have tried to investigate the effect of GH on preimplantation development of mouse embryos in vitro. Zygotes and two-cell mouse embryos were cultured without (control) or with GH. For zygotes, the addition of 0.2 micrograms/ml of GH resulted in 77 +/- 1% of blastocysts formed and 66 +/- 3% rate of hatching (control 64 +/- 4 and 31 +/- 3%, p < 0.05 and p < 0.01, respectively). For two-cell embryos, the addition of 0.2 micrograms/ml of GH resulted in 87 +/- 2% of blastocysts formed and 60 +/- 4% hatching rate (control 76 +/- 4 and 47 +/- 5%, p < 0.05 for both). This positive effect of GH addition implies that the latter can support mouse preimplantation development in vitro and it suggests, along with its local action on the ovary and its possible effects, via the insulin-like growth factor system, on the tubal and uterine epithelium, a continuous role of this hormone in reproductive physiology from follicular maturation to embryonic development and, possibly, implantation.

Animals↗
PubMed1994

The effect of compounds altering the cAMP level on reversing the 2-cell block induced by hypoxanthine in mouse embryos in vitro.

The possibility of reversing the hypoxanthine induced 2-cell block in mouse embryos when cultured in conditions supplemented with compounds that increase (FSH, hMG, IBMX, hCG) or inhibit (GnRH-analogue) cAMP was assessed. When embryos were cultured in Ham's F-10 without hypoxanthine supplemented with each of the above compounds, no inhibition of blastocyst development was observed. Embryos were then cultured in Ham's F-10 with hypoxanthine supplemented again with each compound. For the addition of GnRH-analogue or FSH, the rate of blastocyst formation was comparable with that of the control medium with hypoxanthine alone. Instead, the addition of IBMX or hMG reversed the induced block. There was no reversible effect for the addition of 2 micrograms/ml hCG while the latter was observed with higher doses. The results from GnRH-analogue and IBMX addition show that, contrary to what was found for oocytes, stimulation of cAMP reverses the hypoxanthine-induced block in mouse embryos. FSH and hCG also had effects opposite to those observed for oocytes. It is unknown why hMG (FSH + LH) reverses the block. A lower cAMP degradation rate resulting in a higher cAMP level is a possible explanation. Our results provide further evidence that cleavage arrest by hypoxanthine has a different mechanism than the hypoxanthine-induced arrest of meiosis.

1-Methyl-3-isobutylxanthine↗
PubMed1993

Follicular fluid inhibin levels in relation to age in patients in an in vitro fertilization and embryo transfer programme.

Inhibin (INH), oestradiol (E2) and progesterone (P) were measured in the follicular fluid (FF) of 22 patients 28-38 years old (Group A) and 11 patients 43-47 years old (Group B) who had received gonadotrophin stimulation in an in vitro fertilization and embryo transfer (IVF-ET) programme. The results indicated that INH, E2 and P levels were significantly lower and the E2/P ratio was higher in FF of Group B patients (older women) compared to those of Group A. There were six single pregnancies among patients of Group A. No difference was observed in follicular fluid INH, E2 and P levels as well as in E2/P ratio between pregnant and non-pregnant patients of Group A (Group A1 and Group A2, respectively). A positive correlation was found between FF concentrations of E2 and P, E2 and INH and P and INH in the three Groups and a negative one between INH and the E2/P ratio in Group B. It seems likely that ovarian INH and E2 production are controlled by different mechanisms and that INH response to ovarian hyperstimulation is altered by advancing age.

Adult↗