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At least 19 recordsLinked to original sources
PubMed1993

Survey results on the current practice of ovum donation. Ovum Donor Task Force of the Psychological Special Interests Group of the American Fertility Society.

OBJECTIVE: To investigate how many programs currently have an ovum donor program and to examine the current state of the art in ovum donor programs regarding management, screening, and implementation. DESIGN: Surveys were sent to members of the Society for Assisted Reproductive Technology (SART) and the Psychological Special Interest Group of the American Fertility Society. RESULTS: Of 160 SART members, 82 surveys were returned. Psychological Special Interest Group surveys were excluded. A trend toward more third party reproduction was seen. There was little uniformity among programs regarding medical or psychological screening. Differences were seen between the screening and administration of ovum and sperm donation. CONCLUSIONS: Unlike sperm donation, ovum donation has begun in the known donor realm. Medical and psychological screening is currently limited in many ovum donor programs and highly variable with both known and anonymous donors. Most programs do use a mental health person as part of the screening process. More guidelines are needed to provide uniformity for the current practice of ovum donation.

Age Factors↗
PubMed1988

An ovum capture inhibitor (OCI) in endometriosis peritoneal fluid: an OCI-related membrane responsible for fimbrial failure of ovum capture.

The present study was conducted to assess the mechanism of in vitro interference with fimbrial ovum capture by the ovum capture inhibitor (OCI) which we have recently demonstrated in endometriosis peritoneal fluid (PF). A golden hamster oviduct exposed to either endometriosis or nonendometriosis PF for 20 minutes at 37 degrees C was examined by scanning electron microscopy. Exposure of the oviduct to endometriosis PF reduced fimbrial activity of ovum capture and developed an OCI-related membrane on the fimbria, by which fimbrial cilia were completely concealed. This was not the case for nonendometriosis PF. Subsequently, an oviduct having been exposed to endometriosis PF was retrogradely flushed, by which the OCI-related membrane was ballooned and removed. The flushed oviduct resumed its activity of ovum capture. The OCI-related membrane appeared a cause of OCI interference with fimbrial ovum capture by preventing the contact between the fimbrial cilia and the cumulus oophorus.

Adult↗
PubMed1990

Laparotomy ovum pick-up and ultrasonic transvaginal ovum retrieval in an IVF program.

Different methods of ovum pick-up were used in an IVF program from January 1, 1988 to January 31, 1989. In the initial stage of the program, laparotomy ovum pick-up with surgical treatment of pelvic diseases resulted in two cases of clinical pregnancy in 1987 with full-term delivery of two healthy babies. Transvaginal ovum pick-up with a needle using an ultrasonic endovaginal transducer was started in late 1987. In 1988-1989 the transvaginal method was employed more frequently than laparotomy, and it has become a routine practice in the IVF program. The ultrasonic endovaginal approach seemed to give a low ovum recovery rate (70.99%), but the fertilization rate was high (85.10%, P less than 0.05), and the rate of embryo transfer was 89.33%. The average number of pre-embryo per transfer was 2.26. These figures were quite similar in the two groups. The ultrasonic transvaginal approach for egg retrieval was noninvasive, easily accepted by patients. We suggest that it can be done repeatedly on one patient to improve the cumulative pregnancy rate. However, the laparotomy for ovum pick-up has shown some special merits and is still indicated in some cases.

Adult↗
PubMed1998

Lectin histochemistry of fallopian tube epithelial cells. Relation to ovum transport and ovum pickup.

OBJECTIVE: Data on histochemical and biochemical characteristics of the human oviduct are scarce. The exact mechanisms of ovum transport and pickup are not fully understood. STUDY DESIGN: Human fallopian tubes were obtained and prepared for histochemistry. We analyzed the distribution of negatively charged groups on the oviduct epithelium and cumulus cells and examined the distribution of glycoconjugates by means of lectin histochemistry. We tested the possible influence of poly-L-lysine and considered ABO blood group expression since these characteristics are determined by specific terminal sugar residues. RESULTS: A negatively charged glycocalyx exists on tubal epithelial cells and cumulus cells. Adherence by affinities similar to sugar-lectin binding forces could be disproven in case of commonly used lectins. Poly-L-lysine inhibited the cationic binding reaction but did not influence lectin binding. The blood group A glycoprotein presents terminal D-N-acetyl-galactosamine residues, which are demonstrated by HPA lectin binding. CONCLUSION: Our study indicates that it is unlikely that electrostatic interactions play a major role in ovum transport or pickup. Since poly-L-lysine has been described as inhibiting ovum transport, sugar-lectin binding affinities seem not to operate in ovum transport or pickup.

ABO Blood-Group System↗
PubMed1999

Fimbrial capture of the ovum and tubal transport of the ovum in the rabbit, with emphasis on the effects of beta 2-adrenoreceptor stimulant and prostaglandin F2 alpha on the intraluminal pressures of the tubal ampullae.

PURPOSE: Our purpose was to elucidate the roles of the ampullar and isthmic portions of the oviduct and the effects of drugs on oviductal contractility. METHODS: Prostaglandin F2 alpha (PGF2 alpha; Ono Pharmaceuticals, Osaka) and oxytocin (Atonin-O; Teikoku Hormone Manufacturing Co. Ltd., Tokyo) were used to stimulate oviductal contractility, and ritodrine hydrochloride (Utemerin; Solvay-Duphar Corp., Denmark) to inhibit the contractility. RESULTS: Both PGF2 alpha and Atonin-O were involved in ovum capture by the ampullar oviduct by stimulating contractility, thus altering the intraductal pressures. Utemerin is effective in inhibiting the enhanced contractility induced by PGF2 alpha and Atonin-O. CONCLUSIONS: Variations in pressure of the ampullar portion of the oviduct seem necessary for the capture of ova expelled from the ovary. Once in the isthmic portion of the oviduct, transport appears to be under the influence of ciliary activity rather than variations in contractility.

Adrenergic beta-Agonists↗
PubMed2002

Biochemical screening for aneuploidy in ovum donor pregnancies.

OBJECTIVE: The purpose of this study was to compare the screening efficacy for aneuploidy detection in ovum donor pregnancies with the use of either the age of the ovum donor or the ovum recipient. STUDY DESIGN: Second-trimester biochemical screening for aneuploidy with alpha-fetoprotein, unconjugated estriol, and human chorionic gonadotropin was performed on maternal serum samples that were submitted prospectively from singleton ovum donor pregnancies. The calculation of aneuploidy risks were performed separately with the age of the ovum donor or the ovum recipient. Risks of >1 in 295 and >1 in 100 were used as cutoff values for the identification of screen-positive pregnancies for Down syndrome and trisomy 18, respectively. RESULTS: Samples from 93 ovum donor pregnancies were identified. The mean ages of the ovum donors and recipients were 27 years (range 20-38.5 years) and 43.6 years (range, 25.9-54.3 years), respectively. When the age of the ovum donor was used in the determination of aneuploidy risk, there were 9 screenpositive pregnancies (9.7%), whereas the use of the age of the ovum recipient resulted in 76 screen-positive pregnancies (82%). With the use of the McNemar test for paired observations, the proportion of screenpositive pregnancies with the age of the ovum donor (9.7%) compared with the age of the ovum recipient (82%) was statistically significant (P <.0001). The odds of being affected, given a positive result, were 1 in 9 (11%) with the age of the ovum recipient and 1 in 76 (1.3%) with the age of the ovum donor. The only fetus with aneuploidy (trisomy 18) was identified as being screen positive in both the ovum donor and ovum recipient calculations. CONCLUSION: In ovum donor pregnancy aneuploidy risk calculations, the use of the age of the ovum donor instead of the ovum recipient reduces the false-positive rate and improves screening efficacy.

Adult↗
PubMed1983

Smooth muscle of the quail oviduct functions as a stretch receptor during ovum transport.

The present experiments were conducted to test the hypothesis that ovum transport in the quail oviduct is regulated by a time-dependent, stretch-mediated feedback cycle which alters the frequency of contractions. According to this hypothesis, a ligature preventing the forward movement of ovum should reverse the direction of the feedback cycle and an artificial ovum should be transported like the normal ovum. When the ligature was placed in the borderline between magnum and isthmus, it caused the reversal of transport direction after a delay of several minutes. Once the direction had changed, it persisted until the ovum was expulsed through the fimbrial end or until a second reversal was caused by either a second ligature or a minor mechanical impediment at the proximal end of the magnum. The ovum was transported between the ligatures at the mean speed of 1.7 +/- 0.17 mm/min (n = 7) until the ovum broke. An artificial ovum placed in the proximal magnum from which the natural ovum had been removed, was transported like the natural ova. Myoelectrical activity recorded with suction electrodes was statistically similar in both types of experiments and the direction of the frequency gradient changed when the transport direction was reversed. The frequency of the electrical activity of oviductal smooth muscle was significantly higher behind the ovum than in its front whether ova were transported in the direction of shell gland or infundibulum; in the segment maximally stretched by the ovum the activity was significantly lower than in other segments. These observations confirmed the hypothesis and suggest that the quail oviduct functions like a stretch receptor.

Animals↗
PubMed2000

The fimbrio-ovarian relation and its role on ovum picking in unexplained infertility: the fimbrio-ovarian accessibility tests.

OBJECTIVE: To study the ovum pickup mechanism and the fimbrio-ovarian relation in fertile women and cases of unexplained infertility and to design a method for investigation and anticipation of the state of ovum pickup. DESIGN: Prospective clinical study. SETTING: Department of Obstetrics and gynecology Kasr El Aini Hospital, Cairo University, Egypt. PATIENTS: Fifty fertile and 25 cases of unexplained infertility. INTERVENTIONS: In all of cases the fimbrio-ovarian relation is studied by determining the length of the free ovarian border between the ovarian ligament and the fimbria ovarica that contains the corpus luteum (the ovulation border), the site of ovulation on that border and the length of the fimbria ovarica. It is also determined by a simple test "The fimbrio-ovarian accessibility test." The fimbriae are held by non-traumatizing grasper and their ability to reach and/or to cover the ovulation site are taken as a prove for successful ovum pickup. In addition, cases having suspected failed ovum picking are treated by controlled superovulation, also by drilling of the ovary at an accessible site to the fimbria ovarica and by freeing short fimbria ovarica with or without its advancement on the ovulation border. RESULTS: The ovulation site is found to be usually accessible to the fimbrial end of the tube (94%) in the fertile cases and not accessible (92%) in the infertile cases. Correction of the fimbrio-ovarian relation in the infertile cases was associated with a cumulative ongoing pregnancy rate of 68%. CONCLUSION: Failed ovum pickup should be considered one of the important causes of unexplained infertility. The suggested "fimbrio-ovarian accessibility" test may be useful for the elucidation of the state of ovum pickup in infertile cases. Correction of the fimbrio-ovarian relation, to make ovum pickup possible, should be considered a method for treating such cases.

Adult↗
PubMed2003

Placental villitis of unclear etiology during ovum donor in vitro fertilization pregnancy.

OBJECTIVE: Preliminary observations by a single pathologist at our institution revealed a 75% incidence of villitis of unexplained etiology in ovum donor in vitro fertilization pregnancies. Because the incidence of villitis of unexplained etiology in the general population is approximately 10%, we conducted a controlled study to compare the incidence of villitis of unexplained etiology in ovum donor in vitro fertilization pregnancies to that in in vitro fertilization pregnancies that do not use donated ova. STUDY DESIGN: Placental specimens of ovum donor in vitro fertilization pregnancies were matched randomly with pregnancies that resulted from both fresh and frozen/thawed native oocyte in vitro fertilization from March 5, 1995, to October 10, 2001, and examined in a blinded fashion by a single pathologist (D. J. R.) for villitis of unexplained cause. The incidence of villitis of unexplained etiology was analyzed in 27 patients who underwent ovum donor in vitro fertilization versus 37 patients who underwent native oocyte in vitro fertilization. RESULTS: Villitis of unexplained cause occurred in 22.2% of ovum donor in vitro fertilization pregnancies, 10.8% of native oocyte in vitro fertilization pregnancies (fresh and frozen/thawed combined), and 14.3% of frozen/thawed cycles (P=.21). CONCLUSION: Although the incidence was not statistically different than in in vitro fertilization that used native maternal oocytes, there was a 2-fold increase in villitis of unexplained cause in the ovum donor in vitro fertilization placentas, which suggests that immune-related disorders may be increased in ovum donor pregnancies.

Adult↗
PubMed1977

A quantitative analysis of the incidence of certain cytoplasmic structures in the ovum of the rat during cleavage.

The volumetric density of most cytoplasmic organelles in the segmenting ovum of the rat was determined by morphometric techniques described by Weibel, at the 1-, 2-, 4-, and 8-cell stages, and at the early and late blastocyst stages. During the course of cleavage, the volumetric density of mitochondria remained practically unchanged. The volumetric density of the Golgi complex complex was too small to permit assessment of the differences between the individual stages of development. Significant changes were found in both granular and agranular endoplasmic reticulum, secondary lysosomes, multivesicular bodies, lamellar structures and lipid droplets. Granular endoplasmic reticulum was first observed as late as the 8-cell ovum stage and its volumetric density increased further in the early and late blastocysts. The relative volume of agranular endoplasmic reticulum was highest in the 1-cell ovum and decreased during the course of cleavage. The same is true for multivesicular bodies. The volumetric density of secondary lysosomes increased during cleavage, reaching the highest values in the 8-cell ovum. Lamellar structures were the most voluminous part of the cytoplasm of the segmenting ovum at all stages. Their volumetric density, however, decreased during the course of cleavage. Lipid droplets occur in very small quantities in the 1- to 4-cell ova, but at later stages their volumetric density increased. Our findings underline the importance of acquiring quantitative information about changes in cell organelle populations for assessing morphological and functional relationships during the early stages of cleavage of the ovum.

Animals↗
PubMedDate not supplied

Homology model and molecular dynamics simulation of carp ovum cystatin.

In this study, a homology model of carp ovum cystatin was constructed based on the crystal structure of chicken egg white cystatin. The results of amino acid sequence alignment indicate that these two proteins exhibit 36.11% of sequence identity. The resultant homology model reveals that carp ovum cystatin shares similar folds as chicken egg white cystatin, particularly in the conserved regions of Q48-V49-G52 and P98-W99 and the locations of two disulfide bonds, C67-C76 and C90-C110. However, the results of 1 ns molecular dynamics simulations show that carp ovum cystatin exhibits less structural integrity than chicken egg white cystatin in explicit water at 300 K. The relatively hydrophilic Met62 of carp ovum cystatin, corresponding to the hydrophobic Leu68 of human cystatin C and Ile66 of chicken egg white cystatin, may destabilize the hydrophobic core and form a dimeric structure more easily through domain swapping. A total of 16 positively charged residues are equally distributed on the surface of carp ovum cystatin, resulting in agglutination with the negatively charged spermatozoa via electrostatic interaction. Thus, carp ovum cystatin is considered to be important in preventing carp eggs from polyspermy.

Agglutination↗