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J Parinaud

Publications and source records attributed to J Parinaud.

At least 19 recordsLinked to original sources
PubMed1992

Paradoxical ovarian stimulations in the use of LHRH analogs.

In the case of in vitro fertilization, LHRH analogs are used to induce an hypophysary blockage, before the phase of stimulation, via administration of exogenous gonadotropin. During in vitro fertilization attempts using LHRH analogs, the blockage is controlled after 14 days of treatment through measurement of the plasmatic estradiol and pelvic ultra-sonography. In this retrospective study, which concerned 1075 in vitro fertilization cycles, a paradoxical ovarian stimulation with LHRH analogs was observed in 93 cases (8.7%), with high estradiol levels and follicular growth (detected by ultra-sonography), in spite of low FSH and LH levels. In 4 cases, a follicular puncture was performed, which allowed to collect oocytes from which embryos were obtained, thus confirming the observed follicular growth and maturation. The most probable hypothesis explaining this phenomenon seems to be a direct ovarian stimulation, effectuated in vivo by LHRH analogs. This stimulation is only observed in certain patients, and apparently more frequently, with certain LHRH analogs, probably through a variation in the expression of ovarian LHRH receptors.

Estradiol↗
PubMed1992

Paradoxical ovarian stimulations in the use of LHRH analogs.

In the case of in vitro fertilization, LHRH analogs are used to induce a hypophysial blockage before the phase of stimulation, via administration of exogenous gonadotropin. During in vitro fertilization attempts using LHRH analogs, the blockage is controlled after 14 days of treatment by measuring plasmatic estradiol and by pelvic ultrasonography. In this retrospective study, which concerned 1075 in vitro fertilization cycles, a paradoxical ovarian stimulation with LHRH analogs was observed in 93 cases (8.7%) with high estradiol levels and follicular growth (detected by ultrasonography), in spite of low FSH and LH levels. In 4 cases, a follicular puncture was performed, which made it possible to collect oocytes from which embryos were obtained, thus confirming the observed follicular growth and maturation. The most probable hypothesis explaining this phenomenon seems to be direct ovarian stimulation effectuated in vivo by LHRH analogs. This stimulation is only observed in certain patients, and, more frequently it seems, with certain LHRH analogs, which is probably due to a variation in the expression of ovarian LHRH receptors.

Clinical Protocols↗
PubMed1992

Randomized trial of three luteinizing hormone-releasing hormone analogues used for ovarian stimulation in an in vitro fertilization program.

OBJECTIVE: To determine if biochemical differences in luteinizing hormone-releasing hormone analogues (LH-RH-a) have a clinical influence, we studied three of these molecules: buserelin acetate (group B), triptorelin (group T), and leuprorelin (group L). DESIGN: Clinical trial. SETTING: In Vitro Fertilization (IVF) Center. PATIENTS: Two hundred forty-six patients, undergoing their first IVF attempt, were randomly allocated to one group. The analogues were used in a long protocol for ovarian stimulation in an IVF program. RESULTS: After 15 days of LH-RH-a therapy, the follicle-stimulating hormone level was lower in group B (2.9 +/- 1, 4.3 +/- 1.7, 4.8 +/- 2.1 UI/L for B, T, and L groups, respectively; P less than 0.001), although no difference was found in LH and estradiol (E2) levels. After follicular growth stimulation by human menopausal gonadotropins (hMG), E2 level was significantly lower in B group (1,799 +/- 1,101, 2,440 +/- 1,298, 2,137 +/- 1,044 pg/mL for B, T, and L groups, respectively; P less than 0.01), as well as the E2 level per hMG ampule (67 +/- 51, 97 +/- 61, 82 +/- 49 for B, T, and L groups respectively; P less than 0.01). The pregnancy per stimulated cycle rate was not significantly different among the groups. CONCLUSIONS: These results suggest that LH-RH-a could act not only on the pituitary but also on the ovaries. Moreover, these data suggest that buserelin acetate could be preferentially used for high responders and triptorelin for poor responders.

Buserelin↗
PubMed1992

High progesterone concentrations induce acrosome reaction with a low cytotoxic effect.

OBJECTIVE: To determine the optimal conditions to obtain live acrosome-reacted spermatozoa for micromanipulation. DESIGN: Experiments were performed to determine time and dose-dependent effects of calcium ionophore A23187 or steroids on acrosome reaction of fertile donor sperm. The percentages of total reacted and live reacted spermatozoa were assessed with the peanut agglutinin lectin procedure. RESULTS: Incubation with 1 mmol/L progesterone (P) induced 48% +/- 17% acrosome reaction after 6 hours. Motility and viability remained high (49% +/- 3% and 70% +/- 2%, respectively) and thus the percentage of live reacted spermatozoa was 27% +/- 5%. Incubation with A23187 (5 mumol/L for 30 minutes) gave similar results for the percentage of live reacted spermatozoa (26% +/- 4%) but with a lower motility and viability (25% +/- 7% and 53% +/- 2%, respectively; P less than 0.05). CONCLUSIONS: These results show that high concentration of P is an effective way to induce acrosome reaction in preparation for micromanipulation.

Acrosome↗
PubMed1992

Influence of ovarian cysts on the results of in vitro fertilization.

OBJECTIVE: To determine if ovarian cysts are associated with a particular basal endocrine profile and impair follicular growth. DESIGN: Retrospective study. SETTING: In Vitro Fertilization (IVF) Center. PATIENTS: Nine hundred fourteen stimulation cycles stimulated with a combination of luteinizing hormone-releasing hormone analogues (LH-RH-a) and human menopausal gonadotropins (hMG) in a long protocol in an IVF program. RESULTS: After 15 days of LH-RH-a therapy, ovarian cysts (> or = 20 mm) were observed in 8% of cases. These cysts were not related to a particular basal endocrine profile and did not impair follicular growth and IVF results. However, puncturing these cysts enhanced the quality of subsequent follicular growth. On the contrary, cysts appearing during hMG treatment (> or = 25 mm) were related with a lower LH:follicle-stimulating hormone ratio (0.79 +/- 0.52 versus 0.92 +/- 0.74 in absence of cyst) and to a lower ovarian response as assessed by the maximal estradiol level to the total number of hMG ampules ratio (51.6 +/- 36.5 versus 65.9 +/- 47.9 in absence of cyst). However, this difference had no influence on the pregnancy per stimulation rate (18% versus 16% in absence of cyst; not significant). CONCLUSIONS: Results show that the pathogens of ovarian cysts appearing during the blockage phase and during the stimulation phase are different. However, they do not impair the results of IVF, and thus it is not necessary to cancel the attempt in case of ovarian cyst.

Buserelin↗
PubMed1991

The effect of oxytocin on oestradiol-17 beta and testosterone secretion by cultured human granulosa cells.

The effect of oxytocin at different concentrations was tested on the secretion of oestradiol-17 beta and testosterone by cultured human granulosa cells obtained by follicular punctures during in-vitro fertilization (IVF) attempts. Oxytocin had no effect on testosterone secretion, either in the absence or the presence of follicle stimulating hormone (FSH). It had no effect on oestradiol-17 beta in the absence of FSH. However, it decreased the FSH-stimulated secretion of oestradiol-17 beta in a certain number of cases. This inhibitory effect appears to be associated with cells more responsive to FSH and was identified in women found to be successful in achieving pregnancy during IVF attempts.

Androstenedione↗
PubMed1990

Effect of clomiphene citrate on oestrogen secretion by human granulosa cells in culture.

The effect of clomiphene citrate (CC) and 17 beta-oestradiol (E2) on oestrogen secretion was studied in human preovulatory granulosa cells in culture. CC stimulated E2 secretion at 1 and 10 ng/ml (respectively, +36 +/- 14% and +33 +/- 5%) in basal conditions but had no effect on FSH-stimulated E2 secretion. On the other hand, E2 had no effect at any of the tested concentrations (0.1 ng/ml to 1000 ng/ml) on its own production. Since the plasma level of CC obtained in clinical use ranges from 1 to 10 ng/ml, this finding could explain the higher plasma oestrogen levels obtained with CC as compared to human menopausal gonadotrophin.

Androstenedione↗
PubMed1990

Effects of RU486 on progesterone secretion by human preovulatory granulosa cells in culture.

The effects of RU486 on progesterone synthesis were studied in human preovulatory granulosa cells in culture. No effect was observed at 1 and 10 micrograms/mL, but at 100 micrograms/mL, RU486 inhibited the simulation of progesterone secretion induced by LH and cAMP. It is suggested that the main target of RU486 is the cytochrome P450scc function [catalyzing the formation of pregnenolone (D5P) from cholesterol], since no accumulation of D5P or hydroxy derivatives of progesterone was observed. As RU486 is an antiglucocorticosteroid and antiprogesterone agent, the effects of dexamethasone and progesterone were also investigated. Dexamethasone did not modify progesterone secretion, but progesterone inhibited its own synthesis in both the presence and absence of LH. Thus, under these experimental conditions RU486 displayed a progesterone-like effect. However, since the effect of RU486 was observed only at a concentration around 10(-4) M, the mechanism of action may not involve a receptor pathway and may not apply to most clinical circumstances.

Cells, Cultured↗
PubMed1988

Effect of a luteinizing hormone-releasing hormone agonist (Buserelin) on steroidogenesis of cultured human preovulatory granulosa cells.

In order to ascertain whether there is a direct effect of luteinizing hormone-releasing hormone (LH-RH) agonists on ovarian steroidogenesis, human preovulatory granulosa cells were cultured in the presence of an LH-RH agonist (Buserelin, Hoechst Roussel Pharmaceuticals, Paris, France). Cultures were performed without serum but with precursors of estrogens and progestins. In basal conditions, Buserelin, at 1 ng/ml, increased estradiol and progesterone (P) secretion, while at concentrations of 10 and 100 ng/ml, no effect was observed. In the presence of follicle-stimulating hormone (FSH) or LH, Buserelin at 1 and 10 ng/ml did not modify the cell's steroidogenesis. However, at a concentration of 100 ng/ml, Buserelin decreased LH stimulation of P secretion. These results suggest that LH-RH agonists, at concentrations in the range of those obtained in clinical use, can modulate ovarian steroidogenesis by direct action.

17-alpha-Hydroxyprogesterone↗
PubMed1987

Randomized trial of two media used for in vitro fertilization.

Culture media are important components of IVF. Their selection must meet the need for efficiency, and also economic and practical requirements. From these standpoints, we compared two widely used media: Ham's F10 supplemented with cord serum and Menezo B2 used without serum. The test followed a randomized protocol using two series of 159 and 162 oocytes. Since no difference was seen in efficiency assessed from cleavage rate, the discussion focuses on cost and ease of use.

Cleavage Stage, Ovum↗
PubMed1987

Choice of an ovarian stimulation protocol according to the follicular puncture method in an in vitro fertilization programme.

In order to ascertain the adequacy of ovarian stimulation protocols with a type of follicular puncture, 126 women undergoing in vitro fertilization received either combination clomiphene/hMG or hMG alone according to a randomized test protocol. Within both groups patients for whom a pelvic examination was required had laparoscopies, while others had transvaginal ultrasonically guided punctures as far as possible. Clomiphene/hMG was more efficient than hMG alone as assessed from the cleavage rate (68% vs. 54%; p less than 0.01) and the pregnancy per attempt rate (16% vs. 5%; p less than 0.05). Laparoscopic punctures were more efficient than ultrasonically guided punctures (mean number of recovered oocytes: 4.8 +/- 2.6 vs. 3 +/- 2.5; p less than 0.001), but slightly better results were achieved by this latter method in ongoing pregnancy per puncture rate (18% vs. 8%; NS). With ultrasonically guided punctures, stimulation by clomiphene/hMG allowed better oocyte recoveries (3.8 +/- 2.5 vs. 2.3 +/- 1.9, p less than 0.05). Such results constitute an argument for preferential use of the clomiphene/hMG stimulation protocol with ultrasonically guided punctures.

Clomiphene↗
PubMed1987

High density lipoprotein and low density lipoprotein utilization by human granulosa cells for progesterone synthesis in serum-free culture: respective contributions of free and esterified cholesterol.

Human preovulatory granulosa cells cultured in serum- and gonadotropin-free medium secreted progressively less progesterone as time elapsed. Addition of purified high density lipoproteins (HDL) as well as low density lipoproteins [very low density (VLDL) plus low density lipoproteins (LDL)] restored optimal synthesis of progesterone, and HDL was as effective as VLDL + LDL. The use of cholesterol doubly labeled lipoproteins allowed calculation of the proportions of free and esterified cholesterol converted into progesterone. Granulosa cells used either free or esterified cholesterol from VLDL + LDL. In contrast, HDL-esterified cholesterol was a poor substrate for progesterone synthesis, while HDL-free cholesterol was used preferentially. LH increased the use of both kinds of lipoproteins without changing the way in which they were used. Pretreatment of HDL by purified phospholipase A2 increased the conversion of free cholesterol into progesterone. Similar treatment of VLDL + LDL had little effect on progesterone secretion. We conclude that HDL as well as VLDL + LDL can provide cholesterol to human preovulatory granulosa cells and that utilization of HDL-cholesterol may depend on gonadotropin (LH) and enzymatic (phospholipase) regulation.

Cells, Cultured↗
PubMed1987

[Evaluation of the economic burden in the respective indications of in vitro fertilization and tubal microsurgery at a regional hospital center].

The authors have calculated the cost of obtaining and maintaining an intrauterine pregnancy to term by IVF and by tubal surgery according to the four classical indications. They have worked this out from local experience. The indications are: reversal of sterilization, surgery on proximal lesions, surgery on distal lesions and multifocal lesions. IVF is superior to surgery where the lesions are multifocal and possibly also in proximal blocks. But surgery is indicated in a large number of distal blocks and particularly in reversal of sterilization. The authors point out how difficult it is to extrapolate from national or international statistics. The choice must depend particularly on the experience of the local teams.

Costs and Cost Analysis↗
PubMed1986

[Triploidy].

Using their own experience which they described in 1984 and reviewing as well the literature of the condition since that time has led the authors to suggest that triploidy should be considered as a pathological entity with three clinical forms: early abortion, mid-trimester termination and the birth of triploidy fetuses either alive or dead. They discuss the clinical features, the ultrasound appearances, the pathological and anatomical details and the cytogenetics of triploidy. They differentiate this condition from trophoblast disease and from the central hydropic conditions which occur with normal caryotypes. They emphasize that there is a difference in the way classical molar pregnancy evolves and repeat again that the term "embryonic mole" should be avoided.

Diagnosis, Differential↗