SEARCH · PubMed Health

Results for “Fertilization rate”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 523 records · Page 29Linked to original sources

PubMed2000

Follicle-stimulating hormone treatment for men with idiopathic oligoteratoasthenozoospermia before in vitro fertilization: the impact on sperm microstructure and fertilization potential.

OBJECTIVE: To assess the effect of FSH on sperm fertilization potential and sperm intracellular structure in men with oligoteratoasthenozoospermia and a proven low fertilization rate in IVF. DESIGN: Prospective, randomized, partial crossover study. SETTING: IVF Unit, Golda Campus, Rabin Medical Center, Petah Tikva, Israel. PATIENT(S): Forty normogonadotropic, normogonadal men with oligoteratoasthenozoospermia and at least one previous IVF attempt in which fertilization failed or the fertilization rate was <30%. INTERVENTION(S): The men were randomly assigned to treatment with daily injections of 75 IU of FSH or 150 IU of FSH for at least 60 days before IVF treatment. A control group of men underwent an IVF cycle without treatment and then were randomly assigned tojoin group 1A or 1B for an additional IVF cycle with treatment. MAIN OUTCOME MEASURE(S): LH, FSH, and testosterone levels during FSH treatment, evaluation of ultramorphologic changes in sperm by electron microscopy, and comparison of fertilization rates in the control and study groups. RESULT(S): After treatment with 75 IU or 150 IU of FSH, the mean fertilization rates were 19.7% and 20.5%, respectively, compared with a 5.8% fertilization rate in the study control cycles. CONCLUSION(S): Prolonged treatment with FSH results in a significant increase in fertilization rates. This effect may be related to improvements in subcellular components of the sperm.

Acrosome↗

PubMed2001

Embryo score is a better predictor of pregnancy than the number of transferred embryos or female age.

OBJECTIVE: To compare the value of 17 IVF variables, including a new mean score of transferred embryos (MSTE), in predicting pregnancy rate. DESIGN: Retrospective study. SETTING: Private IVF unit. PATIENT(S): Women who underwent 10,000 embryo transfers. MAIN OUTCOME MEASURE(S): Duration of infertility, type of infertility, female age, rank of IVF attempt, type of ovarian treatment, progesterone level, sperm count, sperm motility, sperm morphology, number of retrieved oocytes, number of mature oocytes, maturation rate, number of embryos obtained, fertilization rate, number of transferred embryos, cumulative embryo score (CES), mean score of transferred embryos (MSTE), and pregnancy rate. RESULT(S): Outcome of IVF-ET was significantly correlated with female age, type of infertility, number of retrieved oocytes, number of mature oocytes, maturation rate, embryos obtained, fertilization rate, transferred embryos, CES, and MSTE. Multivariate analysis demonstrated that MSTE was a better predictor of pregnancy than the number of transferred embryos and female age. CONCLUSION(S): Embryo quality is the best predictor of pregnancy. The embryo score described herein should be used in IVF-ET programs to choose the best embryos for transfer.

Adult↗

PubMed2002

Reproductive potential of fresh and cryopreserved epididymal and testicular spermatozoa in consecutive intracytoplasmic sperm injection cycles in the same patients.

OBJECTIVE: To determine if the cryopreservation of epididymal and testicular spermatozoa alters their reproductive potential by examination of patients who underwent consecutive cycles of ICSI using fresh and then cryopreserved spermatozoa. DESIGN: Retrospective review. SETTING: Tertiary care university hospital. PATIENT(S): One hundred sixty-two consecutive cycles of ICSI were analyzed. Thirteen patients were identified as having undergone treatment with freshly retrieved epididymal spermatozoa; these patients subsequently underwent treatment with spermatozoa cryopreserved from that cycle. Eighteen patients underwent ICSI with freshly retrieved testicular spermatozoa; these patients subsequently underwent treatment with spermatozoa cryopreserved from that cycle. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Fertilization rates and pregnancy rates. RESULT(S): The fertilizing capacity of epididymal spermatozoa remained unchanged after cryopreservation and subsequent thawing, with fertilization rates of 58% and 57% for fresh and cryopreserved spermatozoa, respectively. Testicular spermatozoa, however, showed a significant decrease in fertilizing capacity after cryopreservation when compared with freshly retrieved spermatozoa (52% and 71%, respectively). Pregnancy rates appeared unaffected by the cryopreservation of epididymal spermatozoa (fresh, 3/13; frozen, 2/13) or testicular spermatozoa (fresh, 2/18; frozen, 5/18). CONCLUSION(S): This study offers further evidence that motile epididymal spermatozoa retain their fertilizing capacity after cryopreservation. The data presented on testicular spermatozoa suggest that although cryopreservation may reduce the fertilizing capacity of testicular spermatozoa, there is no decrease in pregnancy rates.

Adult↗

PubMed2000

Treatment versus no treatment of transient hyperprolactinemia in patients undergoing intracytoplasmic sperm injection programs.

The aim of our study was to investigate the effect of increased plasma prolactin levels on oocyte and fertilization rate in patients undergoing in vitro fertilization (IVF) intracytoplasmic sperm injection (ICSI) treatment. We identified 135 patients with transient or borderline hyperprolactinemia, measured in the mid and late follicular phase and in the mid-luteal phase of the cycle before ovarian stimulation. The patients were assigned to either the no treatment group (76 patients) or the treatment group (59 patients). The treated group underwent treatment with cabergoline or bromocriptine before ovarian stimulation, until there was a decrease of plasma prolactin levels, and the therapy was continued also during the ICSI programme. Both groups received a gonadotropin-releasing hormone (GnRH) agonist and were subsequently stimulated with follicle-stimulating hormone (FSH) up to the day of human chorionic gonadotropin (hCG) administration. The untreated group needed a significantly lower number of FSH ampoules than the treated group to reach the day of hCG administration (38.1 +/- 18.2 versus 43.9 +/- 28.5; p < 0.05). No correlation was found between the two groups on the peak estradiol level achieved, the progesterone level at hCG administration and the numbers of oocytes retrieved. The number of oocytes with superior morphology (87.9% versus 80.4%; p < 0.05), the fertilization rate (70.8 +/- 28.0 versus 60.8 +/- 28.5; p < 0.03), and the mean number of embryos transferred (3.6 +/- 1.6 versus 3.2 +/- 1.5; p < 0.05) were significantly higher in the patients whose hyperprolactinemia was left untreated. In conclusion, we found that transient hyperprolactinemia is positively associated with ICSI outcome, in particularly with oocyte quality and fertilization rate.

Adult↗

PubMed2005

Evaluation of Dorset, Finnsheep, Romanov, Texel, and Montadale breeds of sheep: V. Reproduction of F1 ewes in spring mating seasons.

Objectives were to estimate effects of sire breed (Dorset, Finnsheep, Romanov, Texel, and Montadale), dam breed [Composite III (CIII) and northwestern whiteface (WF)], mating season (March and May), and their interactions on reproductive traits of mature F1 ewes in spring mating seasons. A total of 1,099 F1 ewes produced 1,754 litters of 2,995 lambs from exposures to Suffolk rams during March and May mating seasons in 1995 through 1999. Fertility rate and ewe longevity were measured. Number born and litter birth weight were recorded, and number and weight at weaning and 20 wk of age were analyzed separately for dam- and nursery-reared litter mates. Total productivity from 4 to 6 yr of age for each ewe entering the breeding flock was calculated as the sum of 20-wk weights for dam-reared lambs and separately for nursery-reared lambs. Interactions of sire breed x mating season, ewe age x mating season, and ewe age x dam breed were often significant. Interactive effects of sire breed and mating season on fertility rate (P < 0.001) were primarily due to differences in magnitude. Fertility rates of sire breeds for March and May matings, respectively, were 92 and 89% for Romanov, 91 and 72% for Finnsheep, 90 and 52% for Texel, 88 and 52% for Montadale, and 83 and 62% for Dorset. Sire breed x mating season also affected number born (P < 0.03); March and May values were 2.12 and 2.05 for Romanov, 2.00 and 1.94 for Finnsheep, 1.39 and 1.41 for Texel, 1.37 and 1.51 for Montadale, and 1.37 and 1.55 for Dorset, respectively. Interaction of sire breed x dam breed on fertility rate (P < 0.01) was due to change in rank as well as magnitude. Romanov- and Dorset-sired ewes out of CIII dams had greater fertility rates than Romanov- and Dorset-sired ewes out of WF dams. The opposite situation existed for ewes by Finnsheep, Texel, and Montadale sires. Differences between dam breeds (CIII and WF) in total productivity of dam-reared lambs were not detected, whereas ewes exposed in March (78 kg) were more productive (P < 0.01) than those exposed in May (68 kg). Means of sire breeds for total productivity of dam-reared lambs were 47, 65, 70, 70, and 111 kg for Texel, Montadale, Dorset, Finnsheep, and Romanov, respectively (P < 0.001). Superior reproduction of Romanov sired ewes was primarily due to greater fertility rate and prolificacy at each mating season and ewe age. Use of Romanov-crossbred ewes would increase fertility during spring mating, an important constraint of the sheep industry.

Aging↗

PubMed1993

Human sperm hyperactivation and acrosome reaction and their relationships to human in vitro fertilization.

OBJECTIVE: To determine the relationships between human sperm hyperactivation (HA) and acrosome reaction with fertilization of human oocytes in vitro. DESIGN: Prospective analysis of infertile patients undergoing IVF. SETTING: Tertiary center for infertility and assisted reproductive technology. PATIENTS: Fifty-two couples who underwent IVF or GIFT were studied. The male partners had normal semen parameters on routine analyses. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Sperm HA in seminal fluid and after 1 and 6 hours incubation in capacitation media; sperm acrosome reaction after 0, 6, and 24 hours' incubation in capacitation media; and fertilization rate of human oocytes. RESULTS: The percent spermatozoa with transitional HA after 6 hours of incubation correlated significantly with the fertilization rate of human oocytes. Multivariate discriminant analyses selected six sperm HA and acrosome reaction variables of predictive value in classifying semen samples that achieved fertilization rates above and below 70% threshold. Combination of the selected sperm HA and acrosome reaction variables in seminal fluid and after different times of incubation in capacitation medium classified the samples achieving good or poor fertilization rate with > 80% accuracy. CONCLUSIONS: Assessment of sperm HA and acrosome reaction may be of prognostic value in prediction of human oocyte fertilization rates.

Acrosome↗

PubMed1991

Measurement and analysis of cohort-size variations.

"This article discusses two measures of cohort-size variations: the age-standardized cohort size, and the growth rate of the number of births.... The usefulness of the two measures in analysing recent demographic trends is demonstrated....[The author] discusses meanings and usefulness of the ratio of the crude birth rate (CBR)/total fertility rate (TFR) in studying the effects of age structure changes on population growth." The geographical scope is worldwide, with particular attention to China, Indonesia, Japan, the Philippines, and Thailand.

Age Distribution↗

PubMed1987

Reversible inhibition of rabbit sperm-fertilizing ability by cholesterol sulfate.

Experiments were carried out to examine the influences of lipid treatments on the fertilizing ability of rabbit spermatozoa. In vitro insemination of tubal oocytes with in vivo-capacitated sperm resulted in fertilization (IVF) of 81% of the oocytes (38/47) and in vitro development to the morula or blastocyst stage of 92% (35/38) of the embryos within 72 to 96 h. Treatment of capacitated sperm with cholesterol (Ch, up to 100 micrograms/ml) did not reduce the proportion of oocytes fertilized (fertilization rate, 100%, 8/8). Cholesterol-3-sulfate (Chs) at concentrations of 100 and 1,000 micrograms/ml significantly (p less than 0.001) decreased fertilization rates to 13.6% (8/59), and 3.5% (1/29), respectively. Hypercholesterolemic serum (HChS, 1295 mg cholesterol/dl vs. 45 +/- 18 mg/dl in normal serum), incubated for 2 h with in vivo-capacitated sperm, did not inhibit fertilization. However, a decreasing trend in fertilization was associated with increasing levels of HChS cholesterol. ChS effectively inhibited the fertilizing ability of capacitated sperm (p less than 0.05) compared to control, Ch, and HChS. In another experiment the use of ChS at 100 micrograms/ml significantly (p less than 0.05) reduced the fertilization rate from 56.6% (30/53) to 14.3% (7/49). When a phospholipid-enriched serum medium was added to sperm treated with 100 micrograms ChS/ml, the fertilization rate was 57.7% (23/40), which was not significantly (p less than 0.05) different from the fertilization rate of sperm not treated with ChS (56.6%, 30/53). These data suggest that rabbit sperm fertilizing ability can be reversibly inhibited by cholesterol sulfate.

Animals↗

PubMed2000

Follicular fluid concentrations of interleukin-12 and interleukin-8 in IVF cycles.

OBJECTIVE: To investigate the role of interleukin-12 (IL-12) and IL-8 in the periovulatory follicular fluid during in vitro fertilization cycles. DESIGN: A prospective study. SETTING: Reproductive Medicine Unit, Liverpool Women's Hospital, United Kingdom. PATIENT(S): Women undergoing in vitro fertilization treatment. INTERVENTION(S): IL-8 and IL-12 concentrations in follicular fluid samples that had been collected during transvaginal oocyte retrieval were measured using an enzyme-linked immunosorbent assay (ELISA). Cytokine concentrations were correlated to fertilization rates and treatment outcome. MAIN OUTCOME MEASURE(S): Fertilization rates and ultrasonographic evidence of intrauterine pregnancy by 4 weeks after embryo transfer. RESULT(S): Failed fertilization in women with detectable IL-12 was significantly higher (45.5%) than in the IL-12 negative group (6.1%), P=.01. None of the women with detectable IL-12 achieved a pregnancy at the end of the treatment (P=.01). IL-8 was present in the follicular fluid of all women, and no difference in its concentrations was found between the pregnant and nonpregnant groups. No correlation was found between the follicular fluid concentrations of IL-8 and fertilization rates. CONCLUSION(S): The presence of IL-12 in the follicular fluid appears to be associated with a negative outcome in IVF treatment. Interleukin-8 appears to be an essential part of folliculogenesis, although its concentration is not associated with fertilization or implantation rates.

Adult↗

PubMed1996

In vitro fertilization and microinsemination with round spermatids for propagation of nephrotic genes in mice.

The ICGN is an inbred strain of mice with a hereditary nephrotic syndrome of an unknown cause. The disease progresses to renal failure, resulting in the deterioration of the systemic condition and in a drastic reduction of reproductive capacity. The present study was undertaken to determine if in vitro fertilization (IVF) and microinsemination using round spermatids could ameliorate the reduced fertility of ICGN mice. Mature oocytes (9.4 +/- 1.1 per mouse) were obtained from PMSG/hCG-primed females 2 to 5 mo of age. When spermatozoa from males aged 3 to 4 mo was used for IVF, a high fertilization rate (82.6%) was achieved and a high rate of embryos developed into blastocysts (92.6%). When spermatozoa from males aged 5 to 7 mo was used, the rates of fertilization and development to blastocysts were significantly lower (63.9 and 47.1%, respectively; P < 0.001). However, the production rate of offspring after embryo transfer was satisfactory irrespective of the age of males (59.1%). When males older than 9 mo were used, no fertilization was achieved due to the very poor motility of the spermatozoa. Microinsemination techniques with round spermatids (electrofusion and intracytoplasmic injection) resulted in the production of normal offspring from the older males, including one azoospermic case. These findings indicate that a conventional IVF technique and microinsemination using round spermatids can be used for propagating mutant genes which cause poor reproductive ability in mice.

Journal Article↗

PubMedDate not supplied

Fresh and frozen epididymal sperm yield comparable pregnancy rates for intracytoplasmic sperm injection.

To determine if the use of fresh epididymal sperm is superior to frozen-thawed epididymal sperm for intracytoplasmic sperm injection, the authors reviewed the charts on all couples undergoing intracytoplasmic sperm injection at an academic center, using microsurgically aspirated epididymal sperm. Forty-nine couples undergoing intracytoplasmic sperm injection for male factor infertility, due to congenital absence of vas deferens or irreparable post-testicular obstruction were studied. The following parameters were measured: (1) fertilization rate per oocyte injected (two pronuclei at 24 h), (2) chemical pregnancy rate (two consecutively elevated serum b-hCG levels, and (3) clinical pregnancy rate (sonographic identification of fetal heart rate). Fertilization rates were 51 and 41%, chemical pregnancy rates were 27 and 30%, and clinical pregnancy rates were 19 and 27% in the fresh epididymal compared to the frozen epididymal sperm. This study shows no significant difference in outcomes using fresh or frozen epididymal sperm for intracytoplasmic sperm injection. Frozen-thawed sperm guarantees availability of sperm prior to oocyte retrieval.

Adult↗

PubMed2005

Late fertility in Europe: some comparative and historical data.

THE ISSUE: Given the substantial increase in late fertility (at ages 35 and older) in the last few years in Western countries, the paper raises the question of what factors have caused this new trend, and how likely it is to continue. METHODS: Late fertility is measured using the sum of age-specific fertility rates at 35 or more; its contribution to the total fertility rate (in % of the total fertility rate) and the proportion of first childbirths in this fertility is then computed. Late fertility among men is assessed using the same method, where the necessary data are available. The data analysed sometimes date back to the 18th century for women (Sweden), and the early 20th century for men (in France). RESULTS: Late fertility is now much lower than it used to be. Despite the current increase--which can be traced back to the early 1980s for most Western countries, and appears to be much more recent and limited in the former socialist countries--current levels are very low compared with those of the past, among men as well as women. Reduced family size was the main factor in that decline, which became more pronounced as a result of women having a first child at younger ages. The reversal of the trend is due only to postponed childbearing, which must be viewed as part of a general trend towards postponement of all demographic events. More and more of the children born in such circumstances are thus first children. Very late fertility (at 40 or more) has increased, though only slightly, for men as well as women, and age 45 seems to be a limit beyond which few are prepared to have children. Social norms concerning the age limit for a person to have a child could account for the differences from one country to another in that respect. CONCLUSION: Late fertility is likely to continue increasing as long as fertility continues to decrease among young people. However, the increase will continue to be due mostly to the "younger" age groups (under 40 for women, under 45 for men); both biological constraints and social norms probably play a part in the stagnation of very late fertility levels.

Adult↗

PubMed2001

Acrosome index is not an absolute predictor of the outcome following conventional in vitro fertilization and intracytoplasmic sperm injection.

PURPOSE: To investigate if including evaluation of acrosome index (AI) in the semen analysis of teratozoospermic samples could help to predict for which patients intracytoplasmic sperm injection (ICSI) is necessary. METHODS: The fertilization rate, pregnancy rate, and percentage of good quality embryos were compared after performing conventional in vitro fertilization (IVF) and ICSI, respectively, using sibling oocytes. The role of AI was evaluated by dividing patients into two groups; Group A (AI < 7%) and Group B (AI > or = 7%). RESULTS: A significant difference in fertilization rate was observed between Group A and B after conventional IVF. In Group A, the fertilization rate, embryo transfer rate, and percentage of good quality embryos were higher after ICSI than after IVF. In Group B, the fertilization and pregnancy rates were numerically but not significantly higher after IVF compared to ICSI. CONCLUSION: Evaluation of acrosome index will not accurately predict fertilization, although this study shows that a sperm sample with less than 5% normal forms and an AI greater than 7% may achieve a mean fertilization rate > 70% after conventional IVF.

Acrosome Reaction↗

PubMedDate not supplied

Evidence that sperm with low hypoosmotic swelling scores cause embryo implantation defects.

A previous prospective study using matched samples found that sperm with low hypoosmotic swelling (HOS) scores had no adverse effect on fertilization rates but markedly reduced pregnancy and implantation rates. The present study attempted to corroborate or refute the aforementioned study by comparing pregnancy rates in donor-recipient pairs using shared oocytes where the sperm of one of the two males had low HOS scores. The results found no pregnancies from the sperm with low HOS scores versus a 41% live delivered rate for those with normal scores. However, fertilization rates were not affected. This retrospective study thus confirms that sperm with low HOS scores cause implantation defects of the embryos that are formed without affecting fertilization rate, embryo cleavage rate, or embryo quality.

Embryo Implantation↗

PubMed1995

Prospective, auto-controlled study on reinsemination of failed-fertilized oocytes by intracytoplasmic sperm injection.

OBJECTIVE: To evaluate the possible influence of late fertilization after standard IVF on the results of reinsemination of assumed failed-fertilized oocytes by microinjection and to examine the correlation between the effect of aging of (failed-fertilized) oocytes and the ability of these oocytes to become fertilized. DESIGN: Trial 1: Group 1 (injected-day 1), 93 failed-fertilized oocytes injected 1 day after ovum pick-up; group 2 (control), 82 failed-fertilized oocytes with no microinjection performed. Trial 2: Group 1 (ICSI-day 1), 40 failed-fertilized oocytes injected 1 day after ovum pick-up; group-2 (ICSI-day 2), 40 failed-fertilized oocytes injected 2 days after ovum pick-up. In addition, 35 two- to eight-cell stage embryos, obtained after ICSI of IVF failed-fertilized oocytes, were fixed for cytogenetic analysis. MAIN OUTCOME MEASURES: Normal and abnormal fertilization and embryo development. RESULTS: Trial 1: 53% normal (2 pronuclear [PN]) and 25% abnormal (> or = 3PN) fertilization rates were obtained in group 1 (injected-day 1), and 71% of the 2PN and 74% of the > or = 3PN oocytes cleaved with < 50% fragmentation. No pronuclear (> or = 2PN) development occurred in the control group. Trial 2: 45% and 8% normal and 25% and 40% abnormal fertilization rates were obtained, respectively, after ICSI of 1-day-old and 2-day-old failed-fertilized oocytes. Two days after microinjection, 67% and 67% of the 2PN and 80% and 44% of the > or = 3PN oocytes cleaved with < 50% fragmentation in group ICSI-day 1 and in group ICSI-day 2, respectively. CONCLUSIONS: Late fertilization after initial in vitro insemination does not play a role in the high fertilization rate obtained after reinsemination of assumed failed-fertilized oocytes by ICSI. Normal (2PN) fertilization rate, however, decreases strongly and the abnormal (> or = 3PN) fertilization rate increases with oocyte aging and derived embryos seem to have a high incidence of cytogenetic abnormalities.

Cell Nucleus↗

PubMedDate not supplied

[Fertility and health in Mexico].

Fertility, health, and family planning are not independent factors, but rather involve a series of biological and social mechanisms in close interaction with one another. The impact that a high fertility rate has on health is reflected mainly in a rise in the rates of maternal and child mortality. Similarly, fertility has a greater negative effect upon the health of groups characterized by high reproductive risk, high parity, short intergenesic intervals, and unwanted pregnancies. On the other hand, family planning -and specifically the use of contraceptive methods-helps to achieve a lowering of the fertility rate and also has a positive effect on maternal-child health. This situation can be observed in the case of Mexico, where fertility rates and tendencies, as well as maternal and child mortality, have been reduced during the past decade.

Family Planning Services↗

PubMed1992

[Fertilizing ability in vitro of golden hamster spermatozoa after acute testicular X-irradiation].

The present study is concerned with the effect of radiation to the testis on fertilizing ability in vitro using golden hamster spermatozoa. Male hamsters at 6 and 8 weeks of age were given acute testicular X-irradiation (200 kVp, 20 mA, 0.47-0.48 Gy/min). Spermatozoa were collected from the cauda epididymides at different times after irradiation and then they were suspended in fertilization medium. After preincubation for 4-5 hr, the spermatozoa were cultured with the eggs collected from mature hamsters treated with PMSG-hCG. Fertilized eggs were examined for incidence of sperm penetration and formation of pronuclei at 4-5 hr after insemination. The fertilization rate (47.7%) at the 6th week after irradiation with a dose of 2 Gy was much lower in comparison with the control value (92.6%). However, the fertilization rates at the 3rd and 9th weeks after irradiation were 97.7 and 90.6%, respectively. In these period, no difference was found between the irradiated groups and the control groups. From the changes in sperm concentration after irradiation with a dose of 2 Gy, it was found that the fertilization rate was the lowest at the 6th week. The sensitive stage to radiation during spermatogenesis with reference to the reduction of fertilizing ability after irradiation coincides with that of decrease in the sperm concentration and sperm motility. The results of fertilization rate at the 6th week after different doses of X-irradiation (0.25-6 Gy) indicated that the reduction of fertilization rate is nearly expressed as a dose-response relationship.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed2000

[Effects of the gene transfer into sperm mediated by liposomes on sperm motility and fertilization in vitro].

To clarify the problems of gene transfer in the fertility clinic, we investigated the safety and effectiveness of the gene transfer of mouse sperm using the lipofection method. We used the pCAGGS-lacZ plasmid connected with cytomegarovirus enhancer/chicken beta-actin promoter as an adventitious gene. After incubation of the DNA-liposome complex and mouse sperm of epididymis in the medium, we investigated the sperm motility after gene transfer, in vitro fertilization rate of the gene transferred sperm, and gene expression of the fertilized ovum and fetus. Sperm motility was lowered significantly with the increase in DNA density. The fertilization rate for in vitro fertilization was lowered significantly with the increase in DNA density. Gene expression was observed in some of the fertilized ova. In the fetus 12.5 days after embryo transfer, gene transfer was confirmed by the PCR method, but we could not find gene expression by X-gal staining. We proved that the sperm with a gene transferred by the lipofection method could fertilize the ovum and transfer adventitious gene to ova. We speculate that sperm motility and fertility rate were lowered because the introduction of DNA and the DNA-liposome complex destroyed parts of the cell. Development of a sperm fractionation method for DNA transfer and establishment of a method for effective and safe DNA transfer are awaited.

Animals↗