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Y Englert

Publications and source records attributed to Y Englert.

At least 91 records · Page 5Linked to original sources
PubMed1994

Angiotensin II immunoreactivity is elevated in ascites during severe ovarian hyperstimulation syndrome: implications for pathophysiology and clinical management.

OBJECTIVE: To investigate the ovarian renin-angiotensin system (RAS) during severe ovarian hyperstimulation syndrome (OHSS). DESIGN: Simultaneous sampling of blood and ascitic or peritoneal fluid (PF) during therapeutic paracentesis or laparoscopy. SETTING: University Hospital. PATIENTS: Twelve patients were investigated: three patients presenting severe OHSS, three patients with a spontaneous first trimester pregnancy, three normally cycling women during the early luteal phase, and three patients with ascites of nonovarian origin. MAIN OUTCOME MEASURE: Renin-like activity and angiotensin II (ANG II) immunoreactivity were measured simultaneously in the plasma and the ascites or PF. RESULTS: Angiotensin II immunoreactivity was much higher in the ascites or PF than in corresponding plasma during severe OHSS, first trimester pregnancy, and in the early luteal phase, while it was lower in ascites of nonovarian origin. Renin-like activity and ANG II immunoreactivity were the highest in the ascites of severe OHSS and in the PF from part of the patients with a spontaneous first trimester pregnancy. CONCLUSIONS: The present findings argue for the ovarian origin of the elevated renin-like activity and ANG II immunoreactivity in the ascites of severe OHSS and suggest a stimulatory role of hCG on the ovarian RAS whether during severe OHSS or first trimester spontaneous pregnancy. The vasoactive peptide ANG II may contribute to the maintenance of the ascites in severe OHSS but is probably not responsible for the formation of the ascites. The efficiency of paracentesis during severe OHSS could be explained at least partially by the removing of great amounts of ANG II from the peritoneal cavity.

Adult↗
PubMed1993

Abnormal sperm-mucus penetration test predicts low in vitro fertilization ability of apparently normal semen.

OBJECTIVE: To investigate whether Kremer's sperm-mucus penetration test may predict sperm fertilizing ability in IVF. DESIGN: Kremer's test was prospectively performed on semen samples used for 66 consecutive IVF trials and compared with the fertilization rates and fertilization failure rates observed. RESULTS: Fertilization rates were significantly reduced in cases of abnormal Kremer's test (42% versus 51%; n = 745 oocytes with a statistically insignificant increase in fertilization failure rates (21% versus 10%; n = 66 trials). For abnormal semen, fertilization rates (39% versus 39%; n = 208 oocytes) and fertilization failure rates (20% versus 28%; n = 17 trials) were similar regardless of Kremer's test result. For normal semen, an abnormal Kremer's test implied a significant decrease in fertilization rates (44% versus 54%; n = 537 oocytes) with a statistically insignificant increase in fertilization failure rates (21% versus 6%; n = 49 trials). CONCLUSIONS: Abnormal Kremer's test results identify patients with a decreased in vitro fertilizing ability despite apparently normal semen samples and a group with very low fertilizing failure risk in case of normal semen samples and normal Kremer's test. Kremer's test does not add any predictive value to sperm analysis in the case of abnormal semen samples. These observations point out the importance of the male factor in fertilization failure even in the case of normal semen analysis.

Cervix Mucus↗
PubMed1993

The ovarian hyperstimulation syndrome in in-vitro fertilization: a Belgian multicentric study. I. Clinical and biological features.

The multicentric study regroups 128 cases of the ovarian hyperstimulation syndrome (OHSS) in in-vitro fertilization (IVF) and 256 selected controls. Values of serum oestradiol obtained from different laboratories were found to be normally distributed after logarithmic transformation. Comparative study of clinical and biological characteristics indicates that among OHSS patients (i) mean age was lower; (ii) tubal indications for IVF were less frequent; (iii) polycystic ovary-like conditions (i.e. hyperandrogenism, anovulation, luteinizing hormone/follicle stimulating hormone ratio > 2) were more frequent. OHSS patients displayed ovarian hypersensitivity reflected by higher oestradiol peak concentrations in response to lower dosage of human menopausal gonadotrophin and by a steeper slope of oestradiol increment during stimulation. In these patients, the collection of greater numbers of fertilizable oocytes allowed replacement of more embryos with a good vitality score. Ongoing pregnancy rate was found to be higher among the OHSS patients. The following complications were recorded among OHSS cases: abdominal fluid at echographic examination or clinical ascites (86.7 and 71.1%, respectively); pleural and pericardial effusion (21 and 3%, respectively); haemoconcentration (71.1%); electrolytic disorders (6.2%). Although significantly different between groups, clinical and biological parameters under study showed considerable overlap of their distributions in control and OHSS cases. Therefore, these data must be submitted to discriminant analysis in order to derive a formula predictive of the risk of OHSS.

Adult↗
PubMed1992

Comparative auto-controlled study between swim-up and Percoll preparation of fresh semen samples for in-vitro fertilization.

This study compared swim-up and Percoll preparation of fresh semen samples for in-vitro fertilization. Sixty trials of in-vitro fertilization (IVF), 38 with normal semen and 22 with abnormal semen, comprising 734 oocytes were included in the study. Each semen sample was prepared by both a swim-up technique and a simplified discontinuous (50%, 70%, 90%) Percoll gradient. The oocytes for each trial were distributed at random between the two sperm preparations and incubated with the same number of motile spermatozoa. Percoll gradient preparation produced a significantly higher final concentration of spermatozoa than swim-up preparation (mean +/- SEM: 6.6 +/- 1.5 x 10(6)/ml versus 1.9 +/- 0.2 x 10(6)/ml; P less than 0.01) but a significantly lower sperm motility (69 +/- 2% versus 94 +/- 1%; P less than 0.001) and a lower number of normal forms (55 +/- 2% versus 64 +/- 2%; P less than 0.01). The ability of the Percoll gradient method to extract motile spermatozoa was higher than that of the swim-up technique (20 +/- 15.6% versus 0.8 +/- 13.6%). Nevertheless, the rates of fertilization (61%), fertilization failure (18%) and polyspermia (9%), embryo quality evaluated by mean embryo scores (3.8 +/- 0.3) and the mean number of spare embryos frozen per trial (1.4 +/- 0.3) were strictly identical in both groups. The 24 pregnancies (including three from frozen--thawed embryos) obtained in these 60 trials (40% per oocyte retrieval) could not be separated according to the sperm preparation method, as embryos from both groups were replaced together.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Separation↗
PubMed1992

[Immunotherapy of recurrent spontaneous miscarriages (idiopathic abortive disease): preliminary results].

Recurrent spontaneous abortion (greater than or equal to 3 spontaneous miscarriages) represents an entity defined by negative criteria (absence of anatomical, hormonal, autoimmune and chromosomal abnormalities). The immune hypothesis is corroborated by the successes (greater than or equal to 80 %) of specific (paternal leucocytes) or non-specific (intravenous gammaglobulins) immunotherapeutic trials. Studies on the mechanisms of action of those two methods will afford information on the pathogenesis of this condition.

Abortion, Habitual↗
PubMed1992

[Recurrent spontaneous miscarriage].

Spontaneous recurrent miscarriages still represent a poorly defined entity. It is commonly accepted that they include early (1st trimester) spontaneous abortion thus excluding those related to well documented chromosomal, anatomical, hormonal or autoimmune causes such as SLE or anticardiolipin syndrome. There is also a general consensus based upon historical series to require at least three consecutive miscarriages. In a series of 58 consecutive couples with recurrent miscarriages studied at the clinics of immunology of pregnancy, a careful investigation could demonstrate the high incidence of anatomical abnormalities detected by hysterosalpingography and consisting mostly of uterus bicornis or uterus septus. This finding emphasises the importance of this examination. Some of these cases required surgical or endoscopic therapy. Only one patient displayed chromosome abnormalities excluding her from the definition of spontaneous recurrent miscarriage. The other patients were treated either with paternal leucocytes or gammaglobulins.

Abortion, Habitual↗
PubMed1992

Review of scientific contributions by the Belgian medical centers concerned with human in vitro fertilization and embryo transfer (IVF).

In vitro fertilization and embryo transfer (IVF) may be considered as a particular application of modern medical therapeutics linked to human reproduction. The treatment of human sterility therefore involves some fundamental human values such as life, love and death. The quality of this highly technological treatment with fast knowledge of outcome at the end of the patient's menstrual cycle has been evaluated since the early 80s. It is a typically multidisciplinary team effort involving medical doctors, biologists, laboratory technicians, nurses and clerks that is representative of modern medical practice. IVF covers much more than just embryology, as this review will explain. IVF developed in close relation with clinical and experimental research protocols, which are the major topics of this paper. The newness of the techniques used led to the necessary interactions between clinicians and biologists working on animal experimental embryology.

Academic Medical Centers↗
PubMed1991

[Current program of in-vitro fertilization at the Erasmus Hospital: initial results and original ethical aspects].

The clinical results including all in vitro fertilization (IVF) cycles with oocyte pick-up in 1990 are presented. Different types of treatment including classical IVF and embryo transfer, laparoscopic replacement of zygotes in the fallopian tube (ZIFT), IVF with donor sperm (IVF-D), cross fertilization test, embryo freezing, oocyte donation and IVF with epididymal sperm were performed. The total pregnancy rate obtained reaches 38% per oocyte pick-up, 30% of clinical pregnancies (including 4 pregnancies obtained with frozen and thawed embryos). The anticipated "Take Home Baby Rate" will be around 25% per oocyte pick-up, 26 of these 40 pregnancies being today over 20 weeks of gestation. Particular ethical aspects of the program are presented: a study on couple's attitudes regarding embryo freezing as well as the final destination of possibly remaining supernumerary embryos will stress the importance of a precise clear decision on that matter before entering IVF treatment. Indeed the couple's idea on embryo destiny were very precise but also very different. The oocyte donation program has the originality of preserving the donor's anonymity by exchanging the donors recruited by the patients. It will be stressed that this kind of approach combines higher pregnancy chances for the patients, respect of ethical principles linked to gamete donation and gives satisfaction to the patients. The global normalized pregnancy cumulative curve shows that 60% of the couples entering IVF treatment will obtain a child within the first three pick-up cycles.

Embryo Transfer↗
PubMed1990

Fertilization failure in IVF: why and what next?

Among 297 couples who underwent 587 oocyte collection procedures, 95 (16%) total fertilization failures (FF) were observed. This frequency is similar in couples with either normal or only mildly deficient spermatozoa (16.2 and 13.7% respectively) but is almost doubled in cases of moderately and severely defective sperm (26.5%). However, this latter group accounts for only 19% of FF events. The fertilization rate per oocyte (FR) follows an inverse trend. FR was correlated with the final (i.e. after swim-up) sperm count and with initial and final motility of the sperm sample. If the final count and motility were less than 2 x 10(6)/ml and 40% respectively, the FF frequency in the group with partner's spermatozoa was significantly higher and FR significantly lower. FR was inversely correlated with the number of oocytes recovered but FF was found significantly more frequently only when fewer than three eggs were retrieved. No correlation was found between FF and either female causes of infertility, age or dosage of stimulation treatment. However, in the group with donor spermatozoa the FR was significantly lower amongst tubal, endocrinopathic and endometriotic patients (67.6, 67.2 and 56.6 respectively versus 79.7% in harvests from idiopathic cases). FR was decreased and FF increased when ovulation induction resulted from a spontaneous LH peak supplemented with human chorionic gonadotropin (HCG), as compared to induction by HCG alone. In the group using normal or mildly defective spermatozoa, if FF occurs at the first attempt, the frequency of recurrence in further trials is high (29%) and the probability of pregnancy after completed trials is low (12.5%).(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1990

Placental growth hormone as a potential regulator of maternal IGF-I during human pregnancy.

Ninety-three healthy women were investigated during normal pregnancy, and 177 blood samples were obtained at various gestational stages. In 8 of the women, serial measurements were obtained over a period of 16-34 wk from 8 to 40 wk of gestation. In 13 women, daily blood samples were obtained from day 0 to day 6 after delivery. Insulin-like growth factor I (IGF-I) and human placental lactogen (hPL) were measured by radioimmunoassays. Growth hormone (GH) was estimated by two monoclonal antibody-based radioimmunoassays insensitive to physiological concentrations of hPL: the K24 assay, which recognizes only pituitary hGH, and the 5B4 assay, which reacts with all the known pituitary as well as placental GH variants. Placental GH was distinguished from the main pituitary variant through its specific immunoreactivity pattern. Mean plasma levels of IGF-I were relatively stable until 29-30 wk gestation, then increased progressively to reach a maximum at 35-36 wk. Regardless of gestational age, individual IGF-I values exhibited a highly significant positive correlation with placental GH, reflected by 5B4 immunoreactivity, whereas the correlation between IGF-I and hPL was not statistically significant. Considering each 2-wk gestational period separately, we found a positive correlation between IGF-I and 5B4 hGH at 31-32 wk. Conversely, no evidence of correlation was found between IGF-I and hPL at any period. After delivery, IGF-I evolution exhibited a biphasic pattern, with an initial decrease to low values followed by a progressive return toward levels found in nonpregnant healthy women. These results strengthen our previous hypothesis that placental growth hormone is involved in the control mechanism of serum IGF-I levels in normal pregnant women.

Antibodies, Monoclonal↗
PubMed1990

[AIDS: is it an indication for artificial insemination with anonymous donor sperm?].

Such demands raise difficulties, as the physician has to consider (and has to be the defender of) the coming child. A thorough psychological investigation must be conducted, as the couple's motives and those of each partner considered separately are not necessarily in agreement. Most important for the couple are the persistence of common projects and the strengthening of the bonds. The husband wants to survive through a child, to give an ultimate present and to increase the chance of keeping his partner. The wife shows her faithfulness and diminishes her partner's guilt feelings. She is, anyway, in a difficult situation if trying not to become pregnant, especially if she had already expressed a wish for maternity in normal circumstances. Unconscious mechanisms can intervene, such as fantasmatic adultery (through IAD) which reequilibrates the couple: the husband who brought the HIV has to be forgiven, or punished. Also, and most importantly, one has to analyze the prospects for the child, who is at risk of loosing his father, and also his mother: a later transmission of the virus to her cannot be excluded. The child will be confronted by illness and death of his father, and by heavy family secrets. The attitude of the medical team remains problematic: no clearcut attitude prevails.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Pathologic features of placentas from singleton pregnancies obtained by in vitro fertilization and embryo transfer.

Fifty placentas were collected at term from singleton pregnancies resulting from in vitro fertilization (IVF) and intrauterine embryo transfer. Their pathologic features were compared with those of a control group composed of 50 placentas obtained from spontaneous singleton pregnancies. The mean maternal age, mean gestational age, mean fetal weight, sex ratio, and rate of pregnancy complications did not differ. There was also no significant difference between the groups in the mean placental weight and in the incidence of placental pathologic lesions, including extended infarcts, massive perivillous fibrin depositions, chorioangiomas, and placental inflammatory lesions. The incidence of abnormal placental shapes was significantly (P less than .05) greater in the IVF group (22%) compared with the control group (6%). A significant (P less than .025) difference was observed between the groups in the distribution of umbilical cord insertions. The mean distance between the cord insertion and the closest placental margin was significantly (P less than .005) shorter in the group conceived by IVF (3.23 +/- 1.91 cm) than in the control group (4.54 +/- 2.42 cm). A relationship between these placental morphologic features and the superficial implantation and/or inadequate orientation of the blastocyst after IVF and intrauterine embryo transfer is proposed.

Adult↗
PubMed1989

Is fresh or frozen semen to be used in in vitro fertilization with donor sperm?

Sixty-six partners of either severely oligoasthenospermic or azoospermic men were treated by in vitro fertilization with donor sperm (IVF-D), usually (86%) after failure of artificial insemination with donor sperm. One hundred twenty-nine IVF trials were performed with either fresh (59%) or frozen-thawed (41%) donor sperm. Characteristics of sperm preparations were significantly lower in the frozen-thawed group (P less than 0.001). In the latter group, fertilization rates had slightly decreased (but without statistical significance); embryonic vitality scores and cryopreservable spare embryos had significantly decreased (P less than 0.05). However, cumulative ongoing pregnancy rates were strictly equivalent in both groups (40% after three trials). Frozen-thawed sperm thus can be substituted for fresh donor sperm without entailing impairment of the outcome of IVF, and this method must be preferred for its greater safety regarding transmission of human immunodeficiency virus.

Female↗
PubMed1989

[Should one use fresh or frozen sperm in in-vitro fertilization with donors?].

Between 1984 and 1987, 66 women whose partner had severe oligo-asthenoteratospermia or azoospermia underwent in vitro fertilization (IVF) with donor sperm. The mean duration of sterility was 7.5 +/- 3.2 years. Investigations performed in the women showed no abnormality in 30%, pure endocrinopathies in 21% or tubal diseases isolated or associated with other pathologies in 40%. Most of these women (86%) had had previous unsuccessful inseminations with donor sperm. Our study involves 129 attempts of IVF with donor sperm (1 to 3 attempts per patient); the sperm was fresh in 59% of the cases and cryopreserved in 41%. Initial and final motility and sperm density are significantly lower for cryopreserved sperm (p less than 0.001). The fertilization rate is lower with cryo-preserved sperm but the difference is not statistically significant. Moreover, the score of embryonal vitality and the number of embryos that can be cryopreserved are lower with cryopreserved sperm (p +/- 0.05). However the number of pregnancies is identical with one or another type of sperm (40% of the women after 3 IVF). To conclude, cryopreserved sperm may be used for IVF without lowering the percentage of success. In fact, the fertilization rate, the embryonal score and the number of embryos to deep freeze are slightly less with cryopreserved sperm and this difference could reveal to be significant with a larger cohort of patients. But the advantage of fresh sperm must be balanced by the risk of AIDS contamination, avoided with cryopreserved sperm.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Early pregnancy loss and obstetrical risk after in-vitro fertilization and embryo replacement.

Between March 1983 and March 1986, 108 pregnancies were obtained at the IVF clinic of St Pierre Hospital in Brussels. There were 29 chemical pregnancies (26.8%), five ectopic pregnancies (4.6%), 15 abortions (14%) and 59 ongoing pregnancies of over 20 weeks (54%). Patients who had experienced a chemical pregnancy at first trial displayed a significantly higher rate of ongoing pregnancy at their second attempt. Among the 15 cases of abortion, a chromosomal anomaly was detected in two cases and suspected in a third. Four of the five ectopic pregnancies occurred in patients with previously documented tubal pathology. The ongoing pregnancies were distributed as 44 singletons, 13 pairs of twins, one set of triplets and one set of quadruplets. The Caesarian section rates were 21 and 40% for single and multiple pregnancies, respectively. The prematurity rate was low for singletons (4.5%) but reached 46.6% in multiple pregnancies. Two minor malformations were observed and five perinatal deaths occurred; among these latter, four cases were twins. It appears that perinatal pathology is substantially higher among IVF pregnancies than in the normal population. It is clear, however, that most of this difference is accounted for by the considerably higher rate of twin pregnancy displayed by the former group.

Abortion, Spontaneous↗