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This paper examines the current fertility of men and women in the Western area of Sierra Leone and the prospects for future fertility behaviour. Probably due to the effect of rapid economic decline in Sierra Leone since 1980, the desired family size has fallen. But indications are that the preferred completed family size is lower than the desired family size.
The hemizona assay (HZA) was developed to assess human sperm fertilizing potential. This blinded study investigated the relationship between sperm binding to the hemizona and in vitro fertilization (IVF) success (36 patients). Nonliving human oocytes were recovered from excised ovaries and stored. Each zona pellucida was cut into equal hemispheres by micromanipulation. For the HZA, one droplet exposed a hemizona to abnormal spermatozoa, while the control droplet contained the matching hemizona and spermatozoa from normal semen. After 4 hr, the number of tightly bound spermatozoa was counted. Binding to the hemizona was significantly higher for those having IVF success (mean of 36.1 +/- 7, versus 10.4 +/- 4 from the failure group; P less than 0.05). Fewer sperm from the failure group had a strictly normal morphology (3.2 versus 12.7%; P less than 0.05, Kruger method). Tight zona binding was significantly correlated with the percentage motile sperm, percentage normal morphology, and seminal sperm concentration. These results enhanced our confidence that the HZA is diagnostic for identification of patients at high risk of failing to achieve fertilization in vitro.
The possibility of permanent sterility following use of modern contraceptive agents is a concept which causes great concern amongst members of the lay public. However, a thorough review of the literature gives a great deal of reassurance on this topic. The combined oral contraceptive pill causes slight delay, and the injectable contraceptives a moderate delay in the return of fertility following discontinuation, but there is no evidence of a greater likelihood of permanent infertility than in the normal population. The progestogen-only minipill should be risk-free, but final data are lacking. Epidemiological studies do not indicate an increased risk of infertility following IUD use, but it seems likely that there must be a very small number of IUD users who develop permanent infective damage to the Fallopian tubes. Barrier methods and periodic abstinence probably do not have any significant effect on subsequent fertility. Barrier methods could be protective. Therapeutic abortion may have a small deleterious effect on long-term reproductive success, but the data are inconclusive. Detailed information on fertility following use of other methods is not available.
Ten kinds of argininal-containing compounds were examined for their inhibitory effects on the fertilization of the solitary ascidian and on the activities of acrosin and spermosin, trypsin-like proteases isolated from spermatozoa of this animal. Benzyloxycarbonyl-Val-Pro-argininal (I) and benzyloxycarbonyl-Phe-Leu-argininal (II) showed the strongest inhibition on the fertilization. Leupeptin (acetyl-Leu-Leu-argininal, III) was ranked next (I, II greater than III). The activity of ascidian acrosin was susceptible to most of the compounds, among which II was the best inhibitor and followed with I and III (II greater than I, III). Spermosin suffered significant inhibition only with I and II (I greater than II). These results suggest that not only acrosin but also spermosin is involved in fertilization of the ascidian.
High hydrostatic pressure applied between sperm attachment and the onset of cortical granule exocytosis will inhibit this exocytotic event in sea urchin eggs. Such pressure-treated zygotes, nevertheless, are activated and capable of development. Thus, this technique can be used as a tool to study the relationship between cortical granule breakdown and other fertilization-related responses. We have studied whether the exocytosis of cortical granules is necessary for proton efflux (acid release) to occur. Our results indicate that although Ca2+ is released while the eggs are under pressure (a prerequisite for the following events to take place), cortical granule exocytosis and acid release are pressure-sensitive and completely inhibited at pressures above 400 atm (6000 psi) and 275 atm (4000 psi), respectively. However, upon decompression, acid release is initiated which amounts to 65-70% of that seen in the unpressurized controls, suggesting that the efflux mechanism does not require cortical granule exocytosis and must result from some modification of the original plasma membrane of the egg. The remaining 30-35% of the acid release is related to cortical granule exocytosis, since it can be obtained upon induction of the cortical granule fusion 30 min later under atmospheric pressure. The initiation of acid release after decompression indicates that the efflux mechanism is not transiently turned on at fertilization, but undergoing long-term modification; the recovery of the ability to induce cortical granule fusion after fertilization under pressure suggests a refilling of cytoplasmic Ca2+ stores within this time course.
In a case-control study to investigate whether women who use drugs to induce ovulation are at increased risk of conception of a child with a neural tube defect, 571 women who had a fetus or child with a neural tube defect, 546 women who had a fetus or child with other abnormalities, and 573 women who had an apparently normal fetus or child were questioned about infertility, fertility drug use, and related obstetric problems. The rate of maternal fertility drug use around the time of conception was not significantly higher for neural tube defects than for other abnormalities (odds ratio 1.28; 95% confidence interval 0.39, 4.51) or no abnormalities (odds ratio 0.80; 95% Cl 0.27, 2.27). Fertility drug use at any time was not significantly more frequent for neural tube defects than for other abnormalities (odds ratio 1.37; 95% Cl 0.70, 2.74) or no abnormalities (odds ratio 1.05; 95% Cl 0.56, 1.98).
OBJECTIVE: The aim was to evaluate the outcome of fertility-sparing treatment in ovarian borderline tumors and early invasive ovarian cancer. MATERIALS AND METHODS: All women diagnosed with an ovarian borderline tumor or early invasive ovarian cancer who were treated with fertility-sparing surgery at the University Hospital in Lund between 1988 and 2002 were identified and included in the study (n=23). RESULTS: During the follow-up period of a median 92 months, range 11-185 months, no relapse was found in the patients with Stage 1a tumors, including both borderline tumors (n=12) and invasive well-differentiated (n=9) and moderately differentiated (n=1) ovarian cancers. One patient with poorly differentiated ovarian cancer Stage 1c was 13 weeks' pregnant at the time of the primary operation. Although, unilateral oophorectomy was performed she insisted on continuing the pregnancy. At 37 weeks she had a cesarean section and the ovarian cancer was disseminated. Chemotherapy was given but she died less than a year later. None of the other patients received chemotherapy. In total, 30 children were born to 15 patients. Prophylactic removal of the remaining ovary+/-hysterectomy was accepted in only in six of the women after fulfilling their desire to have more children. CONCLUSIONS: Young women with Stage 1a epithelial ovarian cancer and borderline tumors do not have to give up their fertility in order to receive successful and safe treatment of their disease. However, several of these patients do not accept the recommendation of prophylactic oophorectomy of the contralateral ovary and hysterectomy after completion of childbearing.
Human in vitro fertilization requires a safe healthy environment for gamete interaction. This report compares the use of tube cultures with that of organ culture dishes for human in vitro fertilization procedures. Moreover, an oocyte grading system is described that provides an individualized approach for timing of insemination. From the results of this study, the use of organ culture dishes and variable oocyte preincubation demonstrates a significant improvement in human fertilization success in vitro.
The glycosaminoglycans (GAGs) chondroitin sulfate (CS) and heparan sulfate (HS) were assayed in fluid from 178 individual follicles obtained from women after human menopausal gonadotropin ovulation induction for subsequent in vitro fertilization. CS and HS concentrations ranged from 0 to 3.9 and 0 to 18.6 mg/ml, respectively. The percentage of oocytes fertilized was significantly higher when CS concentrations ranged from 0.3 to 0.8 mg/ml (P less than 0.03). As HS levels increased, maturation scores by visual assessment of the egg-corona-cumulus cell complexes increased (P less than 0.05), but the percentage of oocytes fertilized was not affected. Cleavage rates of developing embryos were not related to the concentrations of GAGs.
Fifty semen samples produced for IVF by patients diagnosed as having unexplained infertility were screened for leukocytes, leukocyte subsets, and immature germ cells using a mAB-based staining procedure. Nonfertilizing ejaculates were found to contain significantly larger numbers of immature germ cells, although no significant differences in leukocyte content were observed between groups. Neither sperm density or progressive motility were significantly different between fertilizing and nonfertilizing groups. We conclude that seminal leukocytes have little if any influence on the fertilizing capacity of the spermatozoa in patients undergoing IVF for unexplained infertility, but the presence of large numbers of germinal elements is associated with reduced fertilizing capacity and may be indicative of an immature sperm population.
OBJECTIVE: To examine the predictive value of creatine kinase in human spermatozoa and seminal plasma from patients treated in an IVF program. DESIGN: Prospective, blind clinical study. SETTING: Male infertility clinic. PATIENT(S): Seventy-three patients and 32 fathers (age, <45 years). INTERVENTION(S): Determination of creatine kinase activity in seminal plasma, washed spermatozoa, and swim-up purified spermatozoa from patients treated in an IVF program. MAIN OUTCOME MEASURE(S): Creatine kinase activity in seminal plasma, washed spermatozoa, and swim-up purified spermatozoa. RESULT(S): Creatine kinase activity in washed spermatozoa correlated significantly with normal sperm morphology. No significant correlations were found between creatine kinase activity or creatine kinase isoenzyme ratio in seminal plasma, washed spermatozoa, or swim-up purified spermatozoa and success in the IVF program. The percentage of spermatozoa with normal morphology was significantly lower in patients whose sperm did not fertilize than in patients whose sperm did fertilize oocytes and in the control group of proven fathers. CONCLUSION(S): Total creatine kinase activity and creatine kinase isoenzyme distribution are not sperm function markers for prediction of male fertility in IVF treatment.
OBJECTIVE: To determine if multinucleation in normally fertilized embryos is indicative of poor developmental or clinical pregnancy prognosis and to examine the ovulation induction characteristics associated with multinucleation. DESIGN: Retrospective review. SETTING: A tertiary care institution. PATIENT(S): Patients undergoing IVF-ET cycles (exclusive of other assisted reproductive technologies). MAIN OUTCOME MEASURE(S): Cycles in which embryos had at least 1 multinucleated blastomere were compared with cycles in which all blastomeres exhibited no nucleus or a single nucleus (control). RESULT(S): When >50% of transferred embryos contained multinucleated blastomeres there was a significant reduction in implantation (3.4% vs. 14.7%), clinical pregnancy (9.1% vs. 29.1%), and live birth rates (7.5% vs. 27.6%) when compared with transfers of control embryos. In conjunction with this finding, multinucleate cycles had higher E2 levels and more follicles on the day of hCG administration, a higher number of oocytes retrieved, a higher fertilization rate, and more embryos transferred per patient than did the cycles that produced control embryos. When multinucleated embryos were present, but not transferred, the developmental capacity of the sibling embryo was reduced. CONCLUSION(S): The evaluation of nuclear status using simple light microscopy is predictive of embryo developmental capacity and should be included in the embryo scoring system. The presence of multinucleated blastomeres in normally fertilized embryos is associated with a more effusive response to gonadotropin therapy and is indicative of a poor developmental outcome and lower clinical pregnancy rates.
A field plot study was conducted on two types of paddy soils in the Taihu Lake Region, during the rice season of year 2000 in order to assess phosphorus (P) losses by runoff and vertical leaching, which are considered the two main pathways of P movement from paddy soil into its surrounding water course. Commercial NPK compound fertilizer and single superphosphate fertilizer were applied to furnish 0, 30, 150, and 300 kg applied P ha m(-2). The experiments consisted of three replicates of each treatment in Changshu site and four replicates in Anzhen site, with a plot size of 5 x 6 m2 in a randomized block. Results revealed that the average concentration range for total P (TP) in runoff was 1.857-7.883, 1.038-5.209, 0.783-1.255 and 0.572-0.691 mg P l(-1) respectively for P300, P150, P30 and P0 in Anzhen, while it was 2.431-2.449, 1.578-1.890, 1.050-1.315 and 0.749-0.941 mg P l(-1) respectively in Changshu. In all treatments, particulate P (PP) represented a major portion of the TP lost in runoff, it was 80% in Anzhen, and it was even more (>90%) in Changshu. Phosphate fertilizer treatments significantly affected P concentrations and P loads in the runoff. The mean concentration and average seasonal TP load from the P150 plots were 1.809 mg P l(-1) and 395 g P ha m(-2) season(-1) respectively, and lower than that from the P300 plots (2.957 mg P l(-1) and 652 g P ha m(-2) season(-1)). These were obviously higher than from the P30 (0.761 mg P l(-1) and 221 g P ha m(-2) season(-1)) and P0 (0.484 mg P l(-1) and 146 g P ha m(-2) season(-1)) respectively. There was no significant difference found between the P30 and the P0 in both sites. Under usual P application rate, there were total 31.7 and 20.6 tones P removed by runoff from permeable (Anzhen site) and waterlogged (Changshu site) paddy soils in the southern Jiangsu region (major part of the TLR) in the rice season of the year 2000. But if the P application rate is unusual high, or the Olsen P in soil accumulates to above a certain level, then this could sharply increase in the future. The average concentration of molybdate reactive phosphorus (MRP) in the vertical leachate from the four different P treatments ranged from 0.058 to 0.304 mg P l(-1) in Anzhen and from 0.048 to 0.394 mg P l(-1) in Changshu. P application rate significantly affected the MRP concentration at each depth in both sites, except for the 90 cm in Anzhen. The average MRP loads during the rice season moved by vertical leaching from the four treatments ranged from 163 to 855 g P ha m(-2) season(-1) in Anzhen and 208-1,825 g P ha m(-2) season(-1) in Changshu. Vertical leachate movement does not necessarily mean that it moves towards surface water and contaminate the watercourses in this flat plain paddy soil region, it does, however, imply that P can move down from surface layers of soil to deeper levels.
This essay argues that current procedures of selection for high fertility bulls may overlook young males of potentially high fertility unless these are tested by modified procedures of insemination. Should this suggestion prove to be true, even if only for a small proportion of young bulls that would not previously have been retained as stud animals, then valuable production genes would be kept in the national herd. Modified procedures of introducing the sperm suspension might include (I) deep intra-uterine insemination, (II) insemination into the functional sperm reservoir in the Fallopian tube isthmus, (III) laparoscopic insemination close to the utero-tubal junction, (IV) intra-peritoneal insemination, (V) insemination under conditions of mild superovulation, and (VI) insemination with smooth muscle stimulants and/or sperm stimulating agents added to the suspension. (VII) The potential value of in vitro fertilization assays, such as the zona-free hamster oocyte sperm incorporation test, is also noted. Even if only one of these approaches were found to be fruitful, its impact could be of major significance for the cattle breeding industry.
Studies were conducted to examine the possibility of preserving slaughterhouse-derived buffalo ovaries at 4 degrees C for 0 (control), 12 and 24 h to maintain the developmental competence of the oocytes (experiment 1), to assess the effect of incubation temperature during oocyte maturation on rates of in vitro maturation (IVM) and in vitro fertilization (IVF) of buffalo oocytes and embryo development (experiment 2), and to examine the effect of storage at 25 degrees C for 0 (control), 4 and 8 h of frozen-thawed buffalo sperm and BO and H-TALP as sperm processing and fertilization media on cleavage and embryo development in vitro of buffalo oocytes (experiment 3) in order to optimize the IVF technology in buffalo. Results suggested that storage of ovaries at 4 degrees C for 12 or 24 h significantly (p < 0.05) reduced the developmental potential of oocytes. Incubation temperatures during the IVM influenced the fertilization rate but had no significant effect on maturation and subsequent embryo development. The incubation temperature of 38.5 degrees C during IVM was found to be optimum for embryo production in vitro. Storage of frozen-thawed sperm at 25 degrees C for 8 h significantly (p < 0.05) decreased its ability to cleave the oocytes. Sperm processed in BO medium had significantly (p < 0.05) higher ability to cleave the oocytes than the H-TALP medium.
In order to understand the mechanisms of fertilization in the teleost, the movements of the egg cortex, cytoplasmic inclusions and pronuclei were observed in detail in fertilized medaka Oryzias latipes eggs. The first cortical contraction occurred toward the animal pole region following the onset of exocytosis of cortical alveoli. The cortical contraction caused movement of oil droplets toward the animal pole where the germinal vesicle had broken down during oocyte maturation. The movement of oil droplets toward the animal pole region was frequently twisted in the right or left direction. The direction of the twisting movement has been correlated with the unilateral bending of non-attaching filaments on the chorion. The female pronucleus, which approached the male pronucleus from the vicinity of the second polar body, took a course to the right, left or straight along the s-p axis connecting the male pronucleus and the second polar body. The course of approach by the female pronucleus correlated with the bending direction of the non-attaching filaments that had been determined by rotation of the oocyte around the animal-vegetal axis during oogenesis. The first cleavage furrow also very frequently coincided with the axis. These observations suggest that dynamic responses of medaka eggs from fertilization to the first cleavage reflect the architecture dynamically constructed during oogenesis.
Developmental arrest of 18 ova (about 5%) of 362 fertilized oocytes showing formation of two pronuclei was observed after in-vitro fertilization. In 7 ova the pronuclei were still visible 40 hrs after insemination. Five ova were degenerated after formation of the pronuclei. Cytological analysis of the ova revealed that the arrest of development had occurred at different stages of the cell cycle (interphase to metaphase of the first mitotic division) with one ovum being characterized by a tetraploid chromosome set. Asynchronous development of the pronuclei, which is obviously a cause of early developmental arrest, was observed in 4 ova. According to our observations we would rather transfer fertilized oocytes after cell cleavage (in the 2- to 6-cell stage) than in the pronuclei stage.
Fertilization of golden hamster eggs was blocked both in vitro and in vivo by antibodies produced in rabbits against specific hamster ovarian antigens (HOA). Antibodies against HOA bound to surfaces of the hamster egg zona pellucida and prevented spermatozoa from attaching to the zona and entering eggs in vitro. Fertilization in animals could be blocked for four estrous cycles by a single intraperitoneal injection of anti-HOA immunoglobulin, but not by control immunoglobulin. The in vivo fate of anti-HOA immunoglobulin was analyzed by simultaneous injection of 125I-anti-HOA IgG and control 131I-IgG. Both anti-HOA IgG and control IgG appeared in a variety of organs (lung, kidney, spleen, liver, and uterus) shortly after injection, but disappeared rapidly with no detectable differences in organ half lives. However, in the ovary anti-HOA IgG (but not control IgG) persisted at high levels during the period of infertility. Quantitative precipitin analysis of organ homogenates indicated that a high percentage of anti-HOA IgG in the ovary (but not in the other organs tested) was immunologically indistinguishable from IgG indicating lack of radiolabel metabolism and reincorporation. The results are discussed in terms of the development of a specific immunological block to fertility.