Fertilization rates using intracytoplasmic sperm injection are greater than subzonal insemination but are dependent on prior treatment of sperm

Retention of membrane charge attributes by cryopreserved-thawed sperm and zeta selection

PURPOSE

Mature sperm can be selected based on their negative zeta electrokinetic potential. The zeta selection of cryopreserved sperm is unknown. The objective was to study the effect of zeta processing on the morphology and kinematic parameters of cryopreserved-thawed sperm.

METHODS

Colloid-washed sperm (N = 9 cases) were cryopreserved for 24 h, thawed and diluted in serum-free medium in positive-charged tubes. After centrifugation, the tubes were decanted, serum-supplemented medium was added and the resuspended sperm were analyzed. Untreated sperm and fresh sperm served as the controls.

RESULTS

There were improvements in strict normal morphology in fresh (11.8 +/- 0.3 versus control 8.8 +/- 0.3 %, mean +/- SEM) and thawed (8.7 +/- 0.2 versus control 5.4 +/- 0.2%) sperm after zeta processing. Percent sperm necrosis was reduced after zeta processing (66.0 +/- 0.6 versus unprocessed 74.6 +/- 0.3%). Progression decreased by 50% but not total motility after zeta processing of thawed sperm.

CONCLUSIONS

The results suggested that the cryopreservation process did not impact the sperm membrane net zeta potential and higher percentages of sperm with normal strict morphology, acrosome integrity and reduced necrosis were recovered. The zeta method was simple and improved the selection of quality sperm after cryopreservation but more studies would be needed before routine clinical application.

A simple zeta method for sperm selection based on membrane charge

OBJECTIVE

The objectives were: [1] to develop a simple zeta potential method for sperm isolation; and [2] to analyze the sperm maturity, morphology, kinematic, and DNA parameters.

DESIGN

The phenomenon of sticky sperm adhering to slide surfaces was adapted for collecting charged sperm.

SETTING

Clinical and academic research environment.

PATIENT(S)

Discarded colloid-washed sperm from routine laboratory testing (n = 8).

INTERVENTION(S)

Sperm were centrifuged in serum-free medium and collected for analyses.

MAIN OUTCOME MEASURE(S)

Kinematic parameters, DNA integrity, and maturity.

RESULT(S)

The percentages of mature (73.0% +/- 0.5% vs. control 63.5% +/- 0.5% SEM) and DNA intact sperm (85.0% +/- 0.3% vs. 69.5% +/- 0.5%) increased in the male factor subgroup. Strict normal morphology (19.3% +/- 0.1% vs. 10.0% +/- 0.1%), hyperactivation (7.0% +/- 0.1% vs. 3.6% +/- 0.1%), and progressive motility (29.1% +/- 0.1% vs. 19.9% +/- 0.1%) increased by twofold.

CONCLUSION(S)

The zeta method improved sperm parameters associated with increased fertilization and pregnancy after assisted reproduction procedures. Manipulation from the attaching-detaching process stimulated sperm metabolism without causing premature acrosome reactions. Total motility was unchanged suggesting a lack of association between total motility and zeta potential.

Microinsemination and Nuclear Transfer Using Male Germ Cells

Microinsemination has been widely used in basic reproductive research and in human-assisted reproductive technology for treating infertility. Historically, microinsemination in mammals started with research on the golden hamster; since then, it has provided invaluable information on the mechanisms of mammalian fertilization. Thanks to advances in animal genetic engineering and germ-cell technologies, microinsemination techniques are now used extensively to identify the biological significance of genes of interest or to confirm the genetic normality of gametes produced by experimental manipulations in vitro. Fortunately, in mice, high rates of embryo development to offspring can be obtained so long as postmeiotic spermatogenic cells are used as male gametes-that is, round spermatids, elongated spermatids, and spermatozoa. For some other mammalian species, using immature spermatogenic cells significantly decreases the efficiency of microinsemination. Physically unstable chromatin and low oocyte-activating capacity are the major causes of fertilization failure. The youngest male germ cells, including primordial germ cells and gonocytes, can be used in the construction of diploid embryos by nuclear-transfer cloning. The cloned embryos obtained in this way provide invaluable information on the erasure and reestablishment of genomic imprinting in germ cells.

Pregnancy after ICSI with ejaculated immotile spermatozoa from a patient with immotile cilia syndrome: a case report and review of the literature

This study presents a case of intracytoplasmic sperm injection (ICSI) with ejaculated immotile spermatozoa from a patient with immotile cilia syndrome. Semen analysis of the patient suffering from immotile cilia syndrome revealed an extreme oligoasthenoteratozoospermia (OAT: count <1.4 x 10(6)/ml, 0% motility and 3% normal morphology). Electron microscopy of sperm flagella showed the absence of inner and outer dynein arms. During the ICSI cycle, the hypo-osmotic swelling test (HOS) was used for the identification of viable spermatozoa in the pool of immotile spermatozoa for ICSI. A normal fertilization rate was found in eight out of the 12 oocytes. A first fresh double embryo transfer resulted in a late miscarriage at 21 weeks. A second healthy singleton pregnancy occurred after transfer of two frozen-thawed embryos from the same ICSI procedure. Although only one successful ICSI case of the immotile cilia syndrome combined with HOS is described here, HOS might be a simple but valuable tool to obtain normal fertilization and pregnancy for patients suffering from immotile spermatozoa.

Intra-cytoplasmic sperm injection versus conventional techniques for oocyte insemination during in vitro fertilisation in patients with non-male subfertility

BACKGROUND

In vitro fertilisation (IVF) as treatment for male factor subfertility is associated with lower fertilisation and pregnancy rates than for other indications. Since the late 1980s several assisted fertilisation techniques have emerged and have been rapidly developed to try to enhance results for couples with male factor subfertility, or to help couples with severe male factor for whom conventional IVF was not possible. The techniques of partial zona dissection (PZD) and of subzonal microinjection of spermatozoa into the perivitelline space (SUZI) are by far surpassed by the technique of intra-cytoplasmatic sperm injection (ICSI). ICSI has proven to be the therapy of choice for couples with severe male factor subfertility.

OBJECTIVES

To investigate whether ICSI improves livebirth rate in comparison to IVF in couples with non-male subfertility.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (searched 30 May 2002), the Cochrane Controlled Trials Register (Cochrane Library Issue 2, 2002), PubMed (January 1992 to July 2002) and reference lists of articles.

SELECTION CRITERIA

Trials were included if they compared the effects of these techniques on livebirths, pregnancy and fertilisation outcomes. Only randomised studies were included in this review.

DATA COLLECTION AND ANALYSIS

One study met the inclusion criteria for this review. The study compared ICSI with IVF within couples with non-male infertility. Data was extracted independently by two reviewers.

MAIN RESULTS

There were no randomised data comparing livebirth rates. The single identified study did not find a difference in pregnancy rates (OR 1.4, 95% CI 0.95 to 2.2). There were no randomised data on miscarriage rates, or on other adverse events such as congenital malformations that may be of concern.

REVIEWER'S CONCLUSIONS

Whether ICSI should be preferred to IVF for cases of non-male factor subfertility remains an open question. Further research should report livebirth rates and adverse events.

Laser assisted immobilization of spermatozoa prior to intracytoplasmic sperm injection in humans

BACKGROUND

The conventional method of immobilization of spermatozoa prior to intracytoplasmic sperm injection (ICSI) is mechanical breakage of the tail by pressing it against the bottom of the injection dish.

METHODS

This prospective self-controlled study was set up to evaluate the potential of a non-contact 1.48 microm wavelength diode laser in terms of immobilization. In addition, the fertilization rate and further development potential of such zygotes were investigated. The patients included in our study (n = 60) had oestradiol concentrations >2000 pg/ml, and thus a relatively high number of MII oocytes could be expected. Approximately half the oocytes were injected with laser treated spermatozoa (n = 262, study group) and the other half with mechanically immobilized spermatozoa (n = 252, control group).

RESULTS

No significant differences between the two groups in terms of fertilization rate, early cleavage or blastocyst formation were observed. However, time required for identification, aspiration and injection of a potential spermatozoa was significantly shorter in the laser immobilized sperm group (P < 0.001).

CONCLUSIONS

The application of a non-contact diode laser for sperm immobilization prior to ICSI is a potentially useful alternative to the conventional mechanical approach.

The ratio between carcinoma antigen-125 levels in the seminal plasma and serum may be a marker for fertilization in intracytoplasmic sperm injection

OBJECTIVE

To assess the relationship between tumor marker carcinoma antigen-125 levels in seminal plasma and serum and fertilization rates in an IVF program, using intracytoplasmic sperm injection (ICSI).

DESIGN

A prospective study.

SETTING

IVF Unit, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.

PATIENT(S)

Twenty-five infertile patients with severe oligo-terato-asthenospermia syndrome and 25 fertile male donors.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Serum and seminal plasma carcinoma antigen-125 concentrations and fertilization rate per cycle.

RESULT(S)

In the infertile group, the seminal plasma carcinoma antigen-125 levels ranged from 22.0 to 1,284.0 U/mL (mean level +/- SD, 229.9 +/- 274.2 U/mL). In the normospermic fertile male donors, the seminal plasma carcinoma antigen-125 concentrations ranged from 12.2 to 336.7 U/mL (mean level +/- SD, 110.1 +/- 91.6 U/mL). This difference was statistically significant. The mean +/- SD ratio between the seminal plasma/serum carcinoma antigen-125 levels differed significantly between the infertile group (47.9 +/- 61.3) and the fertile male donors (5.7 +/- 3.5). In the infertile group, the ratio between the seminal plasma/serum carcinoma antigen-125 levels was found to be negatively correlated with the oocyte fertilization rate.

CONCLUSION(S)

The ratio between carcinoma antigen-125 levels in the seminal plasma and serum may be an indirect marker for male infertility and fertilization rate in IVF treatment using ICSI.

In-vitro initiation of forward motility in testicular spermatozoa

Initiation of forward motility in vitro was investigated in goat and ram spermatozoa obtained from the rete testis. No forward motility was generated in the immotile testicular spermatozoa when they were incubated in a modified Ringer's solution containing theophylline (30 mM) and epididymal plasma (2 mg protein/ml). However, these reagents induced non-progressive flagellar movement in approximately 25% of spermatozoa. Bicarbonate (25 mM) induced forward motility in approximately 16% of the goat/ram testicular spermatozoa. Theophylline was essential for the bicarbonate-mediated activation of sperm motility, but epididymal plasma had no significant effect on this activation process. Theophylline activated progressive motility in testicular spermatozoa in a dose-dependent manner, the maximum effect occurring after incubation for 10 min with 30 mM theophylline. The initiation profile of in-vitro motility of goat/ram spermatozoa from the caput epididymis closely resembled that of testicular spermatozoa except that induction of motility in the caput spermatozoa was dependent both on bicarbonate and epididymal plasma. The data indicate that, unlike caput epididymal spermatozoa, initiation of motility in testicular spermatozoa is not dependent on motility-promoting protein(s) in epididymal plasma.

Manipulation of sperm before intracytoplasmic sperm injection improves fertilization rates

OBJECTIVE

To determine the effect of sperm manipulation before intracytoplasmic sperm injection (ICSI) on fertilization rates.

DESIGN

Three methods of sperm manipulation before direct ICSI were compared in two sibling oocyte trials.

SETTING

In vitro fertilization unit within a teaching hospital.

PATIENTS

Patients undergoing infertility treatment using ICSI.

INTERVENTIONS

Oocytes were inseminated by ICSI.

MAIN OUTCOME MEASURE

Fertilization rate.

RESULTS

In the first trial, a standard manipulation technique gave a 67% fertilization rate compared with 64% with a minimal manipulation technique. In the second trial the standard technique gave a significantly greater fertilization rate compared with no prior manipulation (67% versus 45%).

CONCLUSIONS

Manipulation of sperm before direct ICSI is not mandatory for fertilization but significantly improves the fertilization rate.