Birth of infant after transfer of anucleate donor oocyte cytoplasm into recipient eggs.
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Adult↗
Biomedical subjects
J Levron
Publications and source records attributed to J Levron.
Gonadotropins and glucocorticoid therapy for "low responders"--a controlled study.
PURPOSE: A randomized, nonplacebo controlled study was conducted to determine the effect of dexamethasone supplementation to a protocol of gonadotropin therapy in 42 "low-responder patients" aged 32 to 43 years. METHODS: All underwent at least two previous cycles treated by gonadotropins for unexplained infertility, or anovulation. Human menopausal gonadotropin was started on day 4 of the menstrual cycle combined with dexamethasone 0.5 mg administered nightly, as an adjuvant. A group of "low responders" who did not receive dexamethasone served as the controls. The number of follicles, total amount of gonadotropins used, time required for stimulation, fertilization, peak estradiol levels and pregnancy rate were evaluated. RESULTS: The number of developing follicles, estradiol levels, fertilization rate and pregnancy rate did not differ significantly. CONCLUSIONS: Although certain beneficial effects were observed in the literature in some of the infertile patients treated with corticosteroids, the overall results did not support daily, low-dose dexamethasone (long-acting corticosteroid) as a clinically useful adjuvant therapy for "low responders" during gonadotropin therapy.
Adult↗
The development of mouse zygotes after fusion with synchronous and asynchronous cytoplasm.
Cytoplasts with diameters of 40-45, 50-55 and 70-75 microm, derived from mouse oocytes at the germinal vesicle, metaphase II and zygote stages were incorporated into zygotes by electrofusion. Manipulated (n = 867) and culture-control (n = 1114) embryos were cultured in vitro and transferred to pseudo-pregnant recipients at the blastocyst stage. When synchronous cytoplasts measuring 40-45 and 50-55 microm in diameter were incorporated into 138 and 86 zygotes respectively, only one embryo in each group (not significant) became arrested at the 1-cell stage. A total of 124 (89.9 compared with 91. 6% for controls) and 69 embryos (80%, P < 0.001 compared with 91.6% for controls) reached the blastocyst stage respectively. In the first group, 66 out of 106 blastocysts implanted (62.2 compared with 54.9% for controls; not significant), however, only 24 (22.6 compared with 40.2% for controls, P < 0.001) were viable in comparison with controls. There were four groups of zygotes that received metaphase II cytoplasts. In the first group, 200 zygotes were fused with 40-45 microm cytoplasts. The second group of 145 zygotes were fused with cytoplasts of the same size derived from aged oocytes. In the third and fourth groups, 38 and 36 zygotes were fused with 50-55 and 70-75 microm cytoplasts respectively. In the first two groups, none of the embryos arrested at the 1-cell stage, but in the other groups the rates were 15 out of 38 (39.5%) and 36 out of 36 (100%) respectively. These zygotes remained arrested at the pronuclear stage and contained large inflated pronuclei. The blastocyst formation rates were 183 out of 200 (91.5 compared with 91.6% for controls, not significant), 109 out of 145 (75.2% lower than controls, P < 0.05) and 14 out of 38 (39.5% lower than controls, P < 0.0001) respectively. In the first two groups 109 and 25 blastocysts were transferred, of which 76 (69.7%) and 15 (60.0%) implanted. This was higher than control embryos (54.9%, P < 0.01) for the first group and similar to controls for the second group. In the first group, 60 embryos (55%) were viable on day 10 of transfer in comparison with controls (40.2%, P < 0.05) while in the second group, 11 embryos (44.0%, not significant) were viable on day 10 of transfer. Zygotes that received germinal vesicle stage cytoplasts developed poorly and the implantation rate was significantly reduced. The present study confirms the importance of the ooplasmic domain in meiotic maturation and preimplantation development. Our results suggest that implantation may be enhanced by transfer of a small amount of metaphase II cytoplasm to the mouse embryo during the 1-cell stage; however, fusion of intact zygotes with cytoplasts > 45 microm appeared largely detrimental. The mechanisms responsible for these changes are yet unknown.
Animals↗
Highly effective method of human oocyte activation.
Fresh and aged unfertilised human oocytes were activated by electroporation and by exposure to isotonic solution of mannitol supplemented with low concentrations of calcium, magnesium and chloride. Over 95% of the fresh oocytes were activated, all showing formation of one pronucleus and extrusion of the second polar body. Oocytes activated 1 and 2 days post-collection showed activation rates of 66.6% and 64.1%, respectively; however, the proportion of one-pronucleate oocytes in these groups was significantly lower (61.6% and 23.5%, respectively). There was no difference in the activation efficiency between the two activation modes. Twelve activated oocytes from the freshly collected group cleaved when left in culture. It is concluded that, in the human, a brief exposure to isotonic solution of mannitol with low concentrations of calcium, magnesium and chloride is a very effective activation stimulus.
Calcium↗
Male and female genomes associated in a single pronucleus in human zygotes.
The ploidy of single-pronucleated human zygotes obtained after conventional in vitro fertilization was determined by fluorescent in situ hybridization (FISH) using multiple simultaneous probes for gonosomes and autosomes. After zona removal the single-pronucleated zygotes were exposed to cytochalasin B, and the pronucleus, surrounded by scant cytoplasm and the plasma membrane (karyoplast), was divided from the rest of the egg (cytoplast). The karyoplasts and the corresponding cytoplasts were analyzed separately by FISH. Of the 16 zygotes analyzed, 10 had haploid pronuclei and 6 were diploid. Four diploid pronuclei contained XY chromosomes, and 2 contained XX chromosomes. These results suggest that during the course of their interaction, human gamete nuclei can associate together and form diploid, single-pronucleated zygotes. These findings confirm a newly recognized variation of human pronuclear interaction during syngamy.
Cell Nucleus↗
Formation of male pronuclei in partitioned human oocytes.
Ninety-five metaphase II human oocytes, aged in vitro for either one day or for two days, and five fresh immature oocytes with no visible germinal vesicle nucleus were partitioned into small cytoplasts after removal of the zona pellucida and exposure to cytochalasin B. Seventy-one metaphase II and four immature oocytes were used as intact zona-free controls. The cytoplasts derived from each partitioned oocyte and all the zona-free whole oocytes were exposed to normal or subfertile donor sperm and later assessed for signs of male pronucleus development. A total of 711 fragments (an average of 8 fragments per partitioned egg) with a mean diameter of about 50 microns were produced from the 100 partitioned oocytes. When exposed to normal sperm, 76% of the 1-day-old metaphase II fragments, 67% of the 2-day-old metaphase II fragments, and 83% of the immature oocyte fragments were fertilized. The mean number of decondensing nuclei per partitioned oocyte was 11.9 for the 1-day-old metaphase II oocytes, 6.4 for the 2-day-old metaphase II oocytes, and 13 for the immature oocytes. The mean number of decondensing nuclei per a whole zona-free oocyte was 5.6 for the 1-day-old metaphase II oocytes (p < 0.05), 6.7 for the 2-day-old metaphase II oocytes (NS), and 13 for the immature oocytes. When exposed to subfertile sperm, 54% of the 1-day-old metaphase II fragments and 28% of the 2-day-old metaphase II fragments were fertilized.(ABSTRACT TRUNCATED AT 250 WORDS)
Cell Nucleus↗
Estradiol- and progesterone-related increases in the renin-aldosterone system: studies during ovarian stimulation and early pregnancy.
To investigate the degree to which endogenous increases in estradiol (E2) and progesterone (P4) are associated with changes in the renin system, we studied eight patients undergoing ovarian stimulation for in vitro fertilization (FSH/human menopausal gonadotropin or clomiphene citrate for 5-11 days, followed by hCG). Three conceived and were followed for up to 62 days after hCG treatment. The others were followed until the end of the luteal phase. During the follicular phase, E2 increased 10-fold, PRA increased 2-fold, and absolute levels of E2 and P4 were positively correlated (r = 0.63; P < 0.05). After ovulation, which was induced by hCG, E2 fell by 50% (day 7), but there was a 50-fold increase in P4 and a further 5-fold increase in PRA. By day 14, E2 increased again in the women who conceived, to levels even higher than those in the follicular phase, and both P4 and PRA increased 2- to 3-fold between days 7 and 14. In contrast, E2, P4, and PRA returned toward baseline levels in the nonpregnant women. On day 21, E2, P4, and PRA remained very high in the pregnant women [E2, 2297 +/- 255 pg/mL (8430 pmol/L); P4, 103 +/- 22 pg/mL (328 pmol/L); PRA, 33 +/- 8 ng/mL.h (9.17 ng/L.s)]. During the luteal phase and early pregnancy, there was a positive relationship between PRA and P4 (r = 0.68; P < 0.05). There was also a positive relationship between PRA and E2 (r = 0.54; P < 0.05); compared to the follicular phase level, PRA was 4-fold higher in the luteal phase at any E2 level. Like renin, urinary aldosterone excretion (UA) increased 5-fold during the luteal phase (day 7) and by a further 3-fold between days 7 and 21 in the pregnant women, reaching very high levels [135 +/- 28 micrograms/day (375 nmol/day); n = 3]. PRA and UA positively correlated (r = 0.59; P < 0.08). Plasma angiotensinogen increased from 2146 +/- 283 ng angiotensin-I/mL (n = 8) to 3682 +/- 607 (n = 8) on day 7 and to 5353 +/- 799 (n = 3) on day 21. Urinary sodium excretion did not fall, and urinary potassium did not increase in coordination with the changes in renin and aldosterone. There was no hypokalemia. These results demonstrate marked increases in plasma renin and UA in coordination with increases in plasma E2 and P4 during ovarian stimulation and early pregnancy, and coordinated falls during luteolysis.(ABSTRACT TRUNCATED AT 400 WORDS)
Adult↗
Assessment of ovarian and uterine blood flow by transvaginal color Doppler in ovarian-stimulated women: correlation with the number of follicles and steroid hormone levels.
OBJECTIVE: To study the changes that occur in vascular resistance to flow in the utero-ovarian circulation and their correlation with the number of follicles and steroid hormone levels in patients undergoing ovarian stimulation with gonadotropin. DESIGN: In a prospective study, the impedance to flow in the intraovarian and uterine vessels was measured by means of transvaginal color flow Doppler imaging throughout the cycle. SETTING: University-based IVF program. PATIENTS: Eleven infertile patients undergoing ovarian stimulation with gonadotropin in preparation for IVF and ET. MAIN OUTCOME MEASURES: Intraovarian, uterine, and arcuate artery blood flow velocity waveforms, follicular growth, and serum E2 and P concentrations throughout the cycle. RESULTS: Pulsatility index (PI) of the intraovarian blood vessels and uterine artery decreased gradually during the follicular and luteal phase. The PI of the arcuate artery did not change significantly. The PI of the intraovarian blood vessels correlated with the number of follicles (> 15 mm; day of hCG). Serum E2 concentrations but not P demonstrated negative linear correlation with the PI of the intraovarian vessels and uterine artery. CONCLUSIONS: Induced cycles are associated with decreased impedance to blood flow in the utero-ovarian circulation. Intraovarian PI correlates negatively at each stage of the cycle with the eventual number of preovulatory follicles. Little or no changes are observed when the response to ovarian stimulation is poor.
Adult↗
Presence of sperm in the perivitelline space predicts fertilization rate after partial zona dissection.
OBJECTIVE: To examine the association of the number of spermatozoa present in the perivitelline space and sperm parameters with fertilization after partial zona dissection in male factor patients. DESIGN: Partial zona dissection was applied in 62 couples (84 cycles). A total of 524 oocytes underwent partial zona dissection (1/8 of the zona circumference) (partial zona dissection group) and 171 sibling oocytes were not manipulated (control group). A total of 326 manipulated oocytes were examined for the presence of spermatozoa in the perivitelline space. SETTING: University-based in vitro fertilization (IVF) program. PATIENTS: Fifty-four (87%) couples had at least one complete failure of fertilization, and 8 (13%) couples had low fertilization rate (< 10%) in previous routine IVF attempts. MAIN OUTCOME MEASURES: Fertilization rate, cleavage rate, and the number of spermatozoa present in the perivitelline space after partial zona dissection. RESULTS: Monospermic and polyspermic fertilization rates were 22.3% and 6.7% in the partial zona dissection oocytes and 8.8% and 0.6% in the nonmanipulated oocytes, respectively. The cleavage rate was similar in the partial zona dissection and control group (69.2% and 66.6%, respectively). A total of 81 partial zona dissection embryos and 10 nonmanipulated embryos were transferred to the uterus of 34 women (39 cycles), resulting in four pregnancies. In 46% (18 of 39) of the patients who had both partial zona dissection and control oocytes, only the manipulated oocytes fertilized. In only 48.8% of partial zona dissection oocytes, spermatozoa were detected in the perivitelline space; in this group of oocytes the fertilization rate was 56.6%. Sperm count and morphology were not clearly correlated with the outcome of partial zona dissection. CONCLUSIONS: The partial zona dissection technique enhances fertilization of subfertile sperm. However, the low efficiency of the procedure, apart from being associated with a high polyspermic rate, is related to the failure of sperm to traverse the slit in the zona pellucida in approximately one half of the manipulated oocytes.
Adult↗
The natural history of multiple pregnancies after assisted reproduction: is spontaneous fetal demise a clinically significant phenomenon?
OBJECTIVE: To determine the rate of spontaneous fetal demise after heartbeats are demonstrated in multiple pregnancies conceived after IVF-ET. DESIGN: Retrospective case series. SETTING: University-based IVF-ET program. PATIENTS: Eighty-one patients in whom initial transvaginal ultrasound (US) study, performed at 5 to 6 weeks of gestation, identified more than one gestational sac. Total number of sacs was 191. INTERVENTION: Patients were followed by serial US examinations. MAIN OUTCOME MEASURE: Outcome of pregnancies. RESULTS: Twenty-four empty gestational sacs were identified in 21 patients, of whom 15 delivered, 2 miscarried, and 4 are currently ongoing beyond first trimester. Of the 167 initially viable embryos, 9 (5%) underwent spontaneous fetal demise. In 5 of these 9 pregnancies, initial US identified significant interfetal size variation. CONCLUSIONS: The rate of spontaneous fetal demise for a specific embryo in multiple gestation, after fetal heartbeats have been identified in early pregnancy, is 5%. This rate is similar to that seen in spontaneous conceptions. The chance of future fetal demise increases if first trimester interfetal size variation is significant.
Abortion, Spontaneous↗
Use of gonadotropin-releasing hormone agonist to cause ovulation and prevent the ovarian hyperstimulation syndrome.
The physiologic basis and clinical applications of the use of GnRHa, rather than hCG, to induce the final stage of oocyte maturation and ovulation in gonadotropin-treated cycles were reviewed. A single mid-cycle dose of GnRHa is able to trigger a preovulatory LH/FSH surge, leading to oocyte maturation and pregnancy in women undergoing ovarian stimulation for IVF/ET or induction of ovulation in vivo. The limited information currently available suggests there are similar pregnancy rates in patients treated with either GnRHa or hCG. The potential clinical advantages of GnRHa over hCG in gonadotropin-treated cycles include 1) the ability to titrate the amplitude and duration of the LH surge, 2) better control of luteal steroid hormone levels, 3) a higher implantation rate, 4) a lower rate of multiple pregnancy, and 5) a reduced risk of OHS. To date, the GnRHa regimen has been effective in preventing OHS in patients at high risk for having this complication.
Estradiol↗
No beneficial effects of human growth hormone therapy in normal ovulatory patients with a poor ovarian response to gonadotropins.
We studied the effects of human growth hormone (hGH) in 7 in vitro fertilization (IVF) patients with normal ovulatory menstrual cycles who showed a low response to ovarian stimulation with follicle-stimulating hormone (FSH) and human menopausal gonadotropin (hMG). Human growth hormone therapy had no significant effect on the number of days of gonadotropic stimulation, on the total amount of hMG administered, on the serum estradiol level on the day of human chorionic gonadotropin injection, or on the IVF outcome. Our preliminary results do not encourage the routine use of hGH to improve IVF outcome in normogonadotropic ovulatory patients who respond poorly to the standard FSH/hMG protocol.
Adult↗
Transvaginal embryo aspiration--a safe method for selective reduction in multiple pregnancies.
OBJECTIVE: To evaluate pregnancy outcome after transvaginal selective embryo aspiration and to compare the results with those reported previously with other techniques for selective abortion. DESIGN: Retrospective case series. SETTING: University-based in vitro fertilization (IVF) program. PATIENTS: Nineteen women with multiple pregnancy who conceived after ovulation induction or IVF/gamete intrafallopian transfer. INTERVENTION: Transvaginal ultrasound-guided aspiration of the embryo(s) was performed at 7 to 8 weeks of gestation. MAIN OUTCOME MEASURES: Early and late complications related to the procedure, outcome of pregnancy, and birth weight. RESULTS: In 18 cases, the initial number of embryos (3 to 7) was reduced to two. In 1 case, the number of embryos was reduced from 4 to 3. None of the remaining fetuses vanished after the procedure. One patient delivered at 25 weeks and all other patients delivered healthy, viable infants (a pregnancy loss rate of 5.3%). CONCLUSIONS: Transvaginal embryo aspiration in early gestation appears to be a simple and relatively safe procedure for selective termination in patients with high-order multiple pregnancy. The cumulative loss rate of selective termination procedures previously reported by others is three times higher than the loss encountered in our series. This earlier procedure may be more acceptable to patients from emotional and religious points of view.
Abortion, Induced↗
Pregnancy after subzonal insertion of cryopreserved spermatozoa from a patient with testicular seminoma.
The first pregnancy established after subzonal insertion of frozen-thawed sperm obtained from a patient with seminoma and severe oligoasthenospermia is reported. A total of 800,000 sperm with a poor progressive motility were recovered after thawing. Three to seven motile spermatozoa were injected into the perivitelline space of each of 10 oocytes, and seven sibling oocytes were coincubated and inseminated with 200,000 motile sperm/mL. Only 1 of the manipulated oocytes fertilized and was transferred to the uterus 65 hours after insemination at the eight-cell stage. A healthy boy weighing 3,600 g was delivered spontaneously at 38 weeks of pregnancy. This report gives hope to patients with testicular malignancy and severely impaired sperm function to maintain their reproductive potential through sperm banking and assisted fertilization techniques.
Adult↗
Highest concentrations of prorenin and human chorionic gonadotropin in gestational sacs during early human pregnancy.
Prorenin is not only the biosynthetic precursor of renin; under certain circumstances in vitro prorenin exhibits reversible intrinsic renin activity and can form angiotensin from renin substrate with or without cleavage of the prosequence. Prorenin is the predominant form of renin synthesized by reproductive organs (ovary, chorion laeve of the placenta, uterine decidua). Its plasma concentrations increases 10-fold throughout pregnancy to 10-100 times that of renin; amniotic fluid prorenin concentration is even higher. No data are available of gestational fluid prorenin concentrations during early pregnancy. For the first 10 weeks there are two gestational cavities; the chorionic cavity then disappears and the smaller amniotic cavity becomes predominant. In this study we measured prorenin, renin, renin substrate and hCG in fluid aspirated from gestational sacs during the first trimester of gestation (predominantly chorionic) and during the second and third trimesters (amniotic). Seventeen patients had amniocentesis during the second or third trimester. Nine patients underwent selective abortion of multiple pregnancy at 7-12 weeks gestation. One patient underwent surgery at 5 5/7 weeks (26 days after conception) for a tubal pregnancy. Second and third trimester amniotic fluid prorenin maximum velocity (Vmax) (16 and 3 sacs, respectively) averaged 6,100 +/- 1,700 (SD) and 1,930 +/- 760 ng/mL.h, respectively (i.e. 1,700 and 540 ng/L.s). In gestational fluid collected before 8 weeks, prorenin Vmax was 10-fold higher, averaging 62,500 +/- 40,000 ng/mL.h (17,000 ng/L.s). The concentration was 140,000 ng/mL.h (39,000 ng/L.s) in the 5 5/7 week tubal pregnancy. In sharp contrast, at 10-12 weeks gestation (n = 3) prorenin Vmax was only 260 +/- 114 ng/mL.h (72 ng/L.s); human CG was also highest before 8 weeks (276,500 +/- 110,900 IU/L) and lowest at 10-12 weeks (1210 +/- 540 IU/L) with intermediate levels occurring later in pregnancy. This study shows that the highest biological levels of prorenin yet detected (close to 1 micrograms protein/mL) occur in gestational sacs in early pregnancy, consistent with a role for the renin-angiotensin system in embryonic development or placentation.
Amnion↗
Induction of preovulatory luteinizing hormone surge and prevention of ovarian hyperstimulation syndrome by gonadotropin-releasing hormone agonist.
OBJECTIVE: To use gonadotropin-releasing hormone agonist (GnRH-a) instead of human chorionic gonadotropin (hCG) to induce oocyte maturation for in vitro fertilization (IVF). DESIGN: Pituitary and ovarian responses to GnRH-a and the outcome of IVF were studied prospectively. Data from patients injected with hCG were analyzed retrospectively. SETTING: Program of IVF at the Rambam (Governmental) Hospital, Haifa, Israel. PATIENTS AND INTERVENTIONS: One or two doses of buserelin acetate 250 to 500 micrograms were administered to six patients with moderate response (Estradiol [E2], 1,494 +/- 422 [+/- SD] pg/mL) and 8 patients with exaggerated response (E2, 7,673 +/- 3,028 pg/mL) to gonadotropin stimulation. Progesterone (P) and E2 were administered for luteal support. MAIN OUTCOME MEASURES: Gonadotropin-releasing hormone agonist effectively triggered luteinizing hormone (LH)/follicle-stimulating hormone (FSH) surge. Mature oocytes were recovered in all patients. Luteal E2 and P were lower than in patients injected with hCG. No signs of ovarian hyperstimulation syndrome were observed. RESULTS: Serum LH and FSH rose over 4 and 12 hours, respectively, and were significantly (P less than 0.05) elevated for 24 hours. Of all mature oocytes, 67% fertilized and 82% cleaved. Four pregnancies were obtained. CONCLUSIONS: A bolus of GnRH-a is able to trigger an adequate midcycle LH/FSH surge, resulting in oocyte maturation and pregnancy. Our preliminary results also suggest that it allows a more accurate control of ovarian steroid levels during the luteal phase and may prevent the clinical manifestation of ovarian hyperstimulation syndrome.
Buserelin↗
Transvaginal ultrasonography in the diagnosis and treatment of infertility.
The use of transvaginal sonography (TVS) in the management of infertility is gaining increasing popularity. The improved resolution and better tissue textural differentiation afforded by TVS makes this technique useful in monitoring ovarian follicular growth, ovulation, and corpus luteum formation, and in evaluating the normal anatomy of the uterus and the cervix and their cyclic response to ovarian steroids. Adnexal and cul-de-sac abnormalities related to infertility can also be identified. TVS-guided procedures can be accurately and safely performed; transvaginal follicular aspiration, gamete or embryo transfer to the Fallopian tube, and fetal reduction are just a few of the procedures recently introduced to reproductive medicine.
Cervix Uteri↗
Criteria for transvaginal sonographic diagnosis of ectopic pregnancy.
Transvaginal ultrasonography was performed in 1150 patients suspected of having an ectopic gestation. The criteria for transvaginal sonographic diagnosis of ectopic pregnancy were established by targeted scanning of the pelvic organs and spaces. Sonographic assessment of tubal pregnancy and its differential diagnosis were based on six criteria: (1) the presence or absence of gestational structures within the fallopian tube, (2) the presence or absence of amorphous material in a dilated fallopian tube, (3) the presence or absence of indirect signs of ectopic pregnancy within the pelvis, (4) the echogenicity of a suspected finding relative to the ovary, (5) the presence or absence of flow (of lacunar origin) within the suspected sonographic finding, and (6) the relationship of a suspected sonographic sign to an intentionally displaced ovary. The latter 3 criteria help differentiate between tubal gestation and a corpus luteum. We believe these diagnostic criteria should be applied when performing transvaginal sonographic scanning of patients suspected of having an ectopic gestation.
Corpus Luteum↗