The Sperm Analysis In Icsi Health And Social Care Essay

Abstract

Background: The new updated World Health Organization criteria for semen analysis on male infertility have affected the semen analysis on manual and computerized assisted semen analysis (CASA) analysis techniques. With sperm motility updated with percentages of progressive, non-progressive and immotile sperm, this may have significant effects in the reproductive medicine industry.

Aims/Objectives: We are going to analysis IVF and ICSI patient figures and compare the outcomes of semen analysed manually and via CASA for significant difference. Also, examine the difference in fertilization rates in IVF and ICSI and how the new WHO semen analysis affects the assisted reproductive technology area.

Methods: All statistical analysis was performed using a standardized computer program IBM SPSS Statistics Version 19, United States. Data was tested for normal distribution, the data considered not to be normally distributed but with a low quantity of normal distributed figures. Data was logged to enable further analysis with comparison of means with paired t-test and one-way ANOVA. Fertilization and spermatozoa motility in manual and CASA analysed figures in IVF and ICSI treatment statistical analysed by paired t-test for significant difference. Unless otherwise stated, P < 0.05 was taken as critical significance value.

Results: ICSI patient’s initial sperm concentration was compared to manual and computerized assisted semen analysis (CASA) concentration, results showed a decrease of 8.04% in manually and 1.65% in CASA preparation and were not statistically different between the groups. Whereas, in motility A grade sperm concentration, an increase of 21.5% in manual and 33.92% in CASA preparation was demonstrated when compared to initial motility A concentration but were also not statistically different between the groups. However, in IVF patients the initial sperm concentration was compared to manual and CASA concentration, results showed a decrease of 35% in manually and 15.35% in CASA preparation and were not statistically different between the groups.

Whereas, in motility A grade sperm concentration, an increase of 14.6% in manual and 14.29% in CASA was demonstrated when compared to initial motility A concentration but were also not statistically different between the groups.

Conclusions: From the 146 patients involved in the study, 46 patients continued treatment with IVF with average pregnancy rate of 58.49% and 49 patients undergo ICSI treatment with an average pregnancy rate of 53.93%. Our findings suggest fertilization is statistically significant with sperm morphology, and suggesting in most cases, CASA system can optimize sperm motility and rate of fertilization.

1. Introduction

Infertility affects around one in six or one in seven UK couples - approximately 3.5 million people. (HFEA, 2013).

Infertility is defined as ‘failure to conceive after frequent unprotected sexual intercourse for one to two years.’ (NICE, 2012)

Many studies have been conducted in the study of infertility. In a study of 11 Canadian centres, the proportion of unexplained infertility ranged from 8% to 37%. These differences were due to differences in the age of the female partners and the duration of infertility, whereas male age, occupation, coital frequency and other factors were not important factors. (Collins and Rowe, 1989).

There are many causes leading to male infertility, conditions such as male accessory gland infection.

Male accessory gland infection (MAGI) is caused by inflammation/infection of the prostate glands, seminal vesicles or epididymides. Causing factors such as sexually transmitted pathogens (e.g. Chlamydia trachomatis) or E.coli, Proteus species, entercocci, or Pseudomonas species can also cause this disorder. This disorder effects sperm quality and fertility but the disease varies among individuals, this is mainly due to severity and the duration of the disease in the patient. The effects on MAGI include decreased ejaculation volume, increased viscosity, abnormal biochemical composition of seminal fluid and low sperm concentration. If epididymides displays damage, the sperm membrane will have decreased acrosomal reactivity and poor capacity to fuse with oocyte membrane and can lead to DNA damage (mutagenesis). The prevalence of MAGI among different regions of the world widely varies. In Europe and in North America, the prevalence among MAGI infertile men is approximately 8 - 10%. In Latin America and Africa, prevalence can be twice as high. (Comhaire et al, 2008)

There are many causes of female infertility, but the most common is tubal-factor infertility. This can occur from a variety of disorders, major cases of tubal diseases are caused by pelvic inflammatory disease. In the US, there is an increased incidence as there are other factors leading towards tubal disease, this includes endometriosis, previous peritonitis, prior tubal surgery and a history of ectopic pregnancy which decreases the chances of a positive prognosis of achieving pregnancy. (Meldrum, 2006)

Before any treatment, is it critical to evaluate the infertile couple as this plays an important role in achieving the finest outcome and avoiding complications. Infertile couples will need to go under many tests and procedures before treatment.

For women, procedures such as a full hormone profile to measure any hormone imbalance, blood tests to find out whether ovulation is present and an ultrasound scan to observe the structure of womb and ovaries. Furthermore, men will require a semen analysis to verify sperm numbers and quality, these include checks on concentration, morphology and motility. Also, sperm antibody test to check for protein molecules that may prevent sperm fertilizing an egg may be used but not routinely. (HFEA, 2013)

Infertile couples will undergo assisted reproductive technology (ART) to achieve pregnancy, most common are in vitro fertilization (IVF) and intra-cytoplasmic sperm injection (ICSI).

ICSI is used widely in the UK, but a recent study has indicated ICSI usage levels are high but did not provide higher live birth rates and fertilization rates. Concluding, there is a need for ICSI guidelines. (Jones et al, 2012)

ICSI (Intra-cytoplasmic sperm injection) has been an important development in ART, results have shown that fertilization rates using ICSI are approximately 70–80% and pregnancy rates are close to 45% (Palermo et al., 2009).

A study on obstetric and perinatal outcome of 1655 ICSI and 3974 IVF single births and 1102 ICSI and 2901 IVF twin births was conducted, this study indicate IVF pregnancies contain a significant higher risk of prematurity compared with ICSI. However, in twin pregnancies, the level of increased stillbirth incidence was present in ICSI. (Ombelet et al, 2005)

However, there have been studies relating to ICSI had no significant impact on the rate of blastocyst development and implantation as well as pregnancy rates. (Schoolcraft et al., 1999)

In addition, a recent study of the growth of children conceived by IVF and ICSI was conducted on 143 IVF and 166 ICSI children with 173 matched naturally conceived controls. The study provides information regarding the growth of IVF and ICSI children up to 12 years with no significant differences were observed on head circumference, height and weight between the three groups. But concluded that further studies must continue to investigate the growth and other outcomes in assisted-conception children as they develop through puberty into early adulthood (Basatemur et al, 2010)

Another development is computer-assisted sperm analysis (CASA), this technique has provided new confidence for the reproductive medicine area. CASA has two advantages by enabling elevated precision and provides quantitative data on the spermatozoa kinematic parameters such as forward progression and hyperactivated sperm motility. (Davis, et al, 1993)

According to the WHO guidelines, with adequate care is taken in preparing specimens, the usage of CASA can now be used for some routine diagnostic intention. But in the WHO semen manual, CASA is still classed as an optional procedure as quality control procedure needs to be established and maintained in a high standard. (WHO, 2010)

The new updated World Health Organization criteria for semen analysis on male infertility have affected the semen analysis on manual and CASA analysis techniques. With sperm motility updated with percentages of progressive, non-progressive and immotile sperm, this may have significant effects in the reproductive medicine industry.

In this study, we will compare two techniques manual and computerized assisted semen analysis (CASA) used in semen analysis and determine if there is a significant difference and how this affects the outcome.

Aims and Objectives

We are going to analysis IVF and ICSI patient figures and compare the outcomes of semen analysed manually and via CASA for significant difference. Also, examine the difference in fertilization rates in IVF and ICSI and how the new WHO semen analysis affects the ART area.

2. Method

2.1 Data collection

Clinical data from 146 patients for IVF, IUI and ICSI were obtained from the regional IVF clinic in St Mary’s Hospitals. 114 patients’ data was suitable for statistical analysis; these were split into treatment types. 46 patients had IVF, 49 patients had ICSI and 19 had IUI treatment. 32 patients did not contain significant data for statistical analysis such as patients discontinuing treatment and manual or CASA data absent so comparison of the treatment was disabled. (Table 1)

Table 1: Number of patients analysed in Central Manchester University Hospitals

Total patients

146

IVF

46

ICSI

49

IUI

19

2.2. Semen diagnostic parameters

Samples from patients are divided into:

Table 2: Diagnostic semen parameters (Department of reproductive medicine, St Mary’s Hospital, 2012)

IVF

Normal sperm morphology equal to or more than 2%

Sperm concentration equal or more than 15 x 10⁶/ml

ICSI

Sperm concentration less than 15 x 10⁶/ml

Normal sperm morphology less than 2%

IUI

Sperm concentration equal or more than 10x10⁶/ml

Normal sperm morphology equal to or more than 5%

Semen sample was then split up into IVF, ICSI or IUI treatment, each sample is then divided into concentration, motility a, b, c and d.

Here are the basic semen motility grades according to World Health Organization:

Table 3: Basic of semen motility grades in semen analysis (WHO 5th edition 2010)

Semen Motility

Description

Grade A

Sperm with progressive motility. These are the strongest and swim fast in a straight line

Grade B

These also move forward but tend to travel in a curved or crooked motion

Grade C

These have non-progressive motility because they do not move forward despite the fact that they move their tails

Grade D

These are immotile and fail to move at all

2.3. Statistical analysis

All statistical analysis was performed using a standardized computer program IBM SPSS Statistics Version 19, United States. Data was tested for normal distribution, the data considered not to be normally distributed but with a low quantity of normal distributed figures. Data was logged to enable further analysis with comparison of means with paired t-test and one-way ANOVA. Fertilization and spermatozoa motility A and B in manual and CASA analysed figures in IVF and ICSI treatment statistical analysed by paired t-test for significant difference. Unless otherwise stated, P < 0.05 was taken as critical significance value.

3. Results

3.1 Initial, computerized assisted semen analysis (CASA) and manual sperm analysis in ICSI

Initial sperm concentration was compared to manual and computerized assisted semen analysis (CASA) concentration, results showed a decrease of 8.04% in manually and 1.65% in CASA preparation and were not statistically different between the groups (Fig 1). Whereas, in motility A grade sperm concentration, an increase of 21.5% in manual and 33.92% in CASA preparation was demonstrated when compared to initial motility A concentration but were also not statistically different between the groups (Fig 2).

In addition, motility B sperm concentration in manual displayed no reduction but CASA showed a decreased amount of 4.23% compared to initial motility B grade concentration and also there were no statistically different between the groups (Fig 3).

Furthermore, a decrease of 1.28% in manual and 2.61% of CASA concentration compared to initial motility C concentration and also were not statistically different between the groups (Fig 4). Finally in comparison to initial motility D concentrations, manual displayed a decrease of 21.15% and 9.11% in CASA, and were not statistically different between the groups (Fig 5).

Fig 1. Sperm concentration (millilitres) with decrease of 8.04% in manual and CASA preparation with decrease of 1.65% in CASA preparation, statistical test: ANOVA (p = 0.315)

Fig 2. Sperm motility A improvement of 21.5% in manual and CASA preparation with 33.92% in CASA preparation. Statistical test: ANOVA (p = 0.440)

Fig 3. Sperm initial motility B with no reduction in manual and 4.23% reduction in CASA semen preparation. Statistical test: ANOVA (p = 0.409)

Fig 4. Sperm initial motility C with a decrease of 1.28% in manual and 2.61% in CASA semen preparation, statistical test: ANOVA (p = 0.533)

Fig 4. Sperm initial motility D with a decrease of 21.15% in manual and 9.11% in CASA semen preparation, statistical analysis: ANOVA (P = 0.266)

3.2 Initial, computerized assisted semen analysis (CASA) and manual sperm analysis in IVF

Initial sperm concentration was compared to manual and CASA concentration, results showed a decrease of 35% in manually and 15.35% in CASA preparation and were not statistically different between the groups (Fig 6). Whereas, in motility A grade sperm concentration, an increase of 14.6% in manual and 14.29% in CASA was demonstrated when compared to initial motility A concentration but were also not statistically different between the groups (Fig 7).

In addition, motility B sperm concentration in manual displayed an increase of 1.5% and CASA showed an increased amount of 9.02% compared to initial motility B grade concentration and also there were no statistically different between the groups (Fig 8).

Furthermore, an increase of 2.36% in manual and 3.49% of CASA concentration compared to initial motility C concentration and also were not statistically different between the groups (Fig 9). Finally in comparison to initial motility D concentrations, manual displayed an increase of 18.37% and 16.55% in CASA, and were statistically different between the groups (Fig 10).

Fig 5. Sperm initial semen concentration with a decrease of 35% in manual and 15.35% in CASA semen preparation, statistical analysis: ANOVA (p = 0.476)

Fig 6. Sperm motility A increases of 14.6% in manual and CASA preparation with 14.29% in CASA preparation, statistical analysis: ANOVA (p = 0.214)

Fig 7. Sperm motility B increases 1.5% in manual and CASA preparation with 9.02% in CASA preparation, statistical analysis: ANOVA (0.222)

Fig 8. Semen motility C increases 2.36% in manual and CASA preparation with 3.49% in CASA preparation, statistical analysis: ANOVA (p = 0.327)

Fig 9. Semen motility D increases 18.37% in manual and CASA preparation with 16.55% in CASA preparation, statistical analysis: ANOVA (p = 0.00)

3.3. Fertilization rates in spermatozoa motility classification in manually analysed figures in IVF treatment

Fig. 10 Significant manual analysed sperm motility A with -ve correlation with fertilization rate, statistical analysis: t-test (p = 0.000)

Fig 11. Significant manual analysed sperm motility B with +ve correlation with fertilization rate, statistical analysis: t-test (p= 0.000)

Fig 12. Significant manual analysed sperm motility C with +ve correlation with fertilization rate, statistical analysis: t-test (p= 0.001)

Fig 13. Significant manual analysed sperm motility D with -ve correlation with fertilization rate, statistical analysis: t-test (p= 0.000)

3.4. Fertilization rates in spermatozoa motility classification in CASA analysed figures in IVF treatment

Fig 14. Significant manual analysed sperm motility A with +ve correlation with fertilization rate, statistical analysis: t-test (p= 0.000)

Fig 15. Significant manual analysed sperm motility B with +ve correlation with fertilization rate, statistical analysis: t-test (p = 0.001)

Fig 16. Significant CASA analysed sperm motility C with -ve correlation with fertilization rate, Statistical analysis: t-test (p = 0.000)

Fig 17. Significant CASA analysed sperm motility D with -ve correlation with fertilization rate, Statistical analysis: t-test (p = 0.002)

3.5. Fertilization rates in manually analysed spermatozoa motility figures in ICSI treatment

Fig 18. Significant manual analysed sperm motility A with +ve correlation with fertilization, statistical analysis: t-test (p = 0.000)

Fig 19. Significant manual analysed sperm motility B with -ve correlation with fertilization, statistical analysis: t-test (p = 0.000)

Fig 20. Significant manual analysed sperm motility C with neutral correlation with fertilization, statistical analysis: t-test (p = 0.000)

Fig 21. Significant manual analysed sperm motility D with -ve correlation with fertilization, statistical analysis: t-test (p = 0.000)

3.5. Fertilization rates in CASA analysed spermatozoa motility figures in ICSI treatment

Fig 22. . Significant CASA analysed sperm motility A with +ve correlation with fertilization, statistical analysis: t-test (p = 0.000)

Fig 23. Significant CASA analysed sperm motility B with -ve correlation with fertilization, statistical analysis: t-test (p = 0.000 )

Fig 24. Significant CASA analysed sperm motility C with -ve correlation with fertilization, statistical analysis: t-test (p = 0.001)

Fig 25. Significant CASA analysed sperm motility D with +ve correlation with fertilization, statistical analysis: t-test (p = 0.000)

4. Discussion

Sperm motility is one of the most vital parameters in assessment in ability of fertilization in ejaculated sperm. Other studies have shown fertilization rates have association with sperm motility. (Donnelly et al, 1998)

In this investigation, statistically significant differences were observed in motility parameters of sperm measured manually and via CASA in IVF and ICSI patients.

Previous studies have shown correlations between sperm movement and fertilization rates. (Amman, 1989)

The results from this study indicate that ICSI and IVF motility A percentage was enhanced in manual and CASA with similar values. But CASA has exceeded manual in the motility percentage in the sperm motility B, C and D in both IVF and ICSI patients.

In IVF patients, fertilization rate appeared to be influenced by manual and CASA analysis, manually analysed motility A contained significant negative correlation but CASA displayed a significant positive correlation. Surprisingly, motility B analysed with fertilization rate presented a significant positive correlation with both manual and via CASA.

However, in ICSI patients, fertilization rate with motility A displayed a significant positive correlation in manual and via CASA techniques. Astonishingly, in motility B, both CASA and manual were significant but with negative correlation.

The results from this study indicate the CASA system has important clinical value and contain significant correlations between motile sperm in IVF and ICSI patients.

In both groups, sperm motility A, B and C concentration were improved by CASA but IVF pregnancy rate was proven to be significantly higher than ICSI patients.

On the other hand, these results indicate manual and CASA analysed sperm motility had no significant impact in percentage of sperm motility.

Other studies have investigated the significant value of the CASA system, a study on CASA parameters during preparation as predictors of pregnancy in intrauterine insemination (IUI) with frozen-thawed donor semen cycles indicate CASA is a solution for the lack of standardization of manual semen analysis but sperm motion parameters obtained by CASA was not accurate. Concluding, the relationship between CASA and clinical value still remain to be clarified. (Fréour et al, 2010)

One the other hand, the Queen’s University of Belfast and Royal Maternity Hospital, Northern Ireland conducted a study on IVF and pregnancy rates, to determine the influence of sperm motility and morphology on IVF outcome using CASA. The study showed that both sperm motility and morphology is significant in prediction of fertilization and pregnancy rates in IVF. (Donnelly, 1998)

However, a study on the accuracy of CASA in pre-freeze and post-thaw specimens with high and low counts of sperm counts and motility indicated CASA results were unreliable due to a number of factors (e.g. quality of counting chamber) affecting semen analysis. Concluding, CASA can support semen analysis but contain many factors which affect the outcome. Also, a correctly performed manual sperm count is less subject to error. (Sidhu et al, 1998)

Studies on CASA systems have also been used in other industries, such as the animal reproductive medicine. A study on the accuracy of the CASA system of pig artificial insemination indicate CASA is reliable after optimising temperature, dilution factor and standardization. Leading to improvement in efficiency and reliability and can record extended periods of sperm motility to predict fertility. (Broekhuijse et al, 2011)

As sperm morphology is one of the useful biomarkers for ART, the WHO criteria for the evaluation of morphology is an important factor in predicting fertilization and pregnancy rates. But a number of other studies have shown morphology has a limiting effect in established fertilization rates. (Bartoov et al, 1993)

WHO criteria for semen analysis on male infertility currently recommends the combination of sperm motility A and B classification, to provide a collective percentage of progressive sperm classification, resulting in only progressive, non-progressive and immotile sperm motility classification.

A recent study showed according to abnormal semen parameters by the 1999 WHO criteria guidelines that 15% of men classified to be infertile. However, in the current WHO criteria guidelines, the 15% would be classified to be at or above the minimum reference values for fertile men. (Murray et al, 2012)

The clinical applications and predictive figures of these changes will affect infertile men as decreased amount of men may be detected for treatable infertility and medical conditions. Also, adjustment in semen analysis criteria will have significant consequences, as this study has indicated there are significant correlations between the relationship of sperm motility and fertilization rates.

This will affect treatment outcomes of infertile couples as IVF and ICSI cut-off values would be altered, this study suggest IVF demonstrated a higher chance of pregnancy with positive correlation of fertilization. However, these results indicate ICSI contains significant relationship between fertilization rates but with negative correlation. Also, factors such as financial cost, opportunity of abnormalities in children and specialist training need to be considered.

A study on the outcome of conventional IVF and ICSI treatment on sibling oocytes on mild male factor infertility verify the rate of blastocyst development and implantation of frozen thawed embryos of IVF are significantly higher than ICSI, and suggested ICSI should be used cautiously as the technique is still under evaluation. (Plachot et al, 2002)

Furthermore, study to observe neonatal and obstetric outcome of pregnancies in IVF and ICSI was conducted, this study indicated between both groups there were no significant differences found, and with the exception of ICSI newborns displayed a lower birth weight. Concluding, ICSI is a secure procedure but further observation should be conducted. (Hourvitz et al, 2005)

In addition, a comparison study on IVF and ICSI with only few oocytes for insemination indicates ICSI is not advantageous as pregnancy, implantation and spontaneous abortion rates did not significantly differ between the groups and contains the factor of time consuming and increased financial costs. (Borini et al, 2009)

Additionally, a comparison study of ICSI and IVF in patients with increased oocyte immaturity showed when fertilization rates of ICSI was calculated the similar technique as IVF, ICSI displayed a lower rate of fertilization. Also, ICSI does not permit for the optimization of an assisted reproductive cycle in patients with increased oocyte immaturity. (Taylor et al, 2008)

Finally, a recent comparison study was carried out on IVF and ICSI for the fertilization of in-vitro matured human oocytes, the results suggest that IVF is a valid fertilization technique due to no significant differences between the groups. Also, the embryo development rates and stages displayed that IVF is just as capable of producing viable embryos as ICSI. Concluding, patients with IVF are likely to achieve blastocyst-stage transfer just as if they were fertilized by ICSI. (Walls et al, 2012)

On the other hand, a recent study was carried out on ICSI to be used in non-male factor infertility, stating examination of thousands of ICSI children has proven ICSI is a largely safe procedure, but should be maintained to be offered to couples for which other assisted reproductive technology cannot offer success. Also, this study indicates no increase in prematurity in ICSI pregnancies compared to IVF pregnancies. Concluding, supporting the use of ICSI and is confident that it will replace other assisted reproductive technology methods in the nearby future. (Orief et al, 2004)

Furthermore, a prospective randomized study in 2001 indicated that ICSI increases fertilization rates and formation of good quality embryos in the absence of male infertile factors. (Khamsi et al, 2001)

Further research in ICSI and IVF should be conducted in the near future as potential underlying setbacks are still unknown.

A study on underlying karyotype abnormalities in IVF and ICSI patients indicated ICSI avoid natural selection which occurs in conventional IVF and natural conception, resulting in a potential of unbalanced karyotypes. (Chantot-Bastaraud et al, 2008)

Also, a retrospective cohort assessment study on IVF and ICSI outcomes in pregnancies has compared IVF/ICSI patients with mothers who naturally conceived and the result shown infants conceived with the use of IVF/ICSI contain a three times increase of high risk of a congenital heart defect as naturally conceived, due to the association of obesity. However, this study recorded viable pregnancy so any pregnancies that were terminated before the gestation period were not included. Concluding, larger studies of the similar study would help to understand underlying problems in infertility treatment. (Wen et al, 2010)

In addition, a pilot study on ART and the risk of autism spectrum disorder (ASD) indicated the rate of ASD was raised in ART conceived children, concluding ART seems to be a significant independent risk factor for ASD but further research should be done. (Zachor et al, 2011)

Although, this is an undersized study, limited to St Mary’s IVF clinic, but these data have demonstrate ICSI has clinical significant, but rates of pregnancy is lower than IVF patients.

5. Conclusion

In conclusion, the results of this retrospective comparative analysis showed that the outcome of IVF and ICSI pregnancies is very similar. From the 146 patients involved in the study, 46 patients continued treatment with IVF with average pregnancy rate of 58.49% and 49 patients undergo ICSI treatment with an average pregnancy rate of 53.93%.

Our findings suggest fertilization is statistically significant with sperm morphology, and suggesting in most cases, CASA system can optimize sperm motility and rate of fertilization.

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