Jurnal Trib Nyooooo

8/13/2019 Jurnal Trib Nyooooo

1/6

Indications for intracytoplasmic sperm injectionL.Hamberger1, K.Lundin, A.Sjogren and B.Soderlund

Department of Obstetrics and Gynecology, University of Gothenburg, S-413 45 Gothenburg, SwedenlrTo whom correspondence should be addressed

Intracytoplasmic sperm injection (ICSI) is thelatest of several microfertilization techniquesthat have been utilized predominantly to over-come severe m ale subfertility, giving fertilizationand term pregnancy rates similar to conven-tional in-vitro fertilization (IVF) (but for otherindications). Even though available data onchildren born after ICSI are very encouraging,the procedure must still be considered as noveland the safety aspect to a great extent unex-plored. In our opinion, therefore, ICSI shouldonly be used for specific indications, and in thiscommunication the non-existent, relative andabsolute indications for performing ICSI areoutlined and discussed. With an apparentlynormal sperm sample, ICSI should not be usedin a first cycle even if only few oocytes areobtained. When there is reason to suspect poorfertilization, ICSI can be used in combinationwith conventional IVF in a split cycle. Thisincludes cases of subnorm al sperm samp les,high titres of antisperm antibodies, or followinga single cycle of poor fertilization using conven-tionalIVF.Absolute indications for ICSI includetwo previous fertilization failures with conven-tional IVF, use of epidiymal or testicular spermsamples, or when only acrosomeless or immotilespermatozoa are available. The fertilizationof oocytes prior to preimplantation geneticdiagnosis is another absolute indication. It is,however, important to keep in mind that forthis novel technique, indications should not berigid, but remain variable with respect to newfindings.Key words: ICSI/IVF/indications/safety

IntroductionMicrofertilization techniques were introducedclinically a decade ago, initially with the sole aimto overcome severe male subfertility. However,over the years other indications have also beenincluded. Zona drilling, partial zonal dissectionand the subzonal sperm injection technique wereall demonstrated to work in principle, but theirclinical success rate was disappointingly low(Cohen et al 1991; Fishel et al 1992;Vanderzwalmen et al 1992; Wolf et al 1992).This situation changed with the introduction ofintracytoplasmic sperm injection (ICSI) since sim-ilar pregnancy rates could be obtained with this newtechnique as w ith conventional in-vitro fertilization(IVF) (Van Steirteghem et al 1993, 1996). Itshould however be emphasized that comparisonsbetween ICSI and conventional IVF in terms ofsuccess rates are probably not relevant, since theyare performed on different classes of infertilecouple, and the proposition that all IVF caseswould have a better chance of success if treatedwith ICSI is not presently proven or valid. Onthe contrary, Petersen et al. (1996) showed thattransferring couples with unexplained infertilityand poor fertilization in conventional IVF to ICSIdid not enhance their success rate. Taking this factinto consideration, it is not certain that the successrates of IVF and ICSI should be expected to beequal, and the only way to study this properlywould be to perform a prospective randomizedtrial among couples for whom both IVF and ICSIis applied for fertilization. It has recently beensuggested that, when fertilization is performed innatural cycles or if only two or three oocytes areobtained in 'poor responders', ICSI should be

1 2 8 European Society for Human Reproduction & Embryology Human Reproduction Volume 13 Supplement 1 1998

byguestonOctober23,2013

http://humrep.oxfordjournals.org/

Downloadedfrom



Downloadedfrom



Downloadedfrom



Downloadedfrom



Downloadedfrom



Downloadedfrom
http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/http://humrep.oxfordjournals.org/


2/6

Indications for ICSIpreferred to conventional IVF (Norman et al1995). In our opinion the chances of fertilizationof a very low number of oocytes are in most casesas good with conventional IVF as with ICSI. Inthis article, the optimal choice of fertilizationtechnique will be discussed in relation to specificpatient groups.

IVF as a first choiceIn our programme when the husband presents withan ejaculated sperm sam ple which after preparation(swim-up or gradient centrifugation), has a totalmotile sperm count (TMC) exceeding ~O.8X1O 6and a morphology (strict criteria) of >5% normalforms, then the couple will undergo conventionalIVF in their first cycle, irrespective of the numberof oocytes (Lundin et al 1997). In cases ofunexpected total fertilization failure reinseminationby ICSI can be performed on day 2 (Sjogren etal. 1995). However, even though term pregnancieshave been reported with this strategy the successrate is very low (Lundin et al. 1996). Also, itcannot be excluded that risks of e.g. polyspermia(if fertilization has already occurred) and/or chro-mosomal damages are increased.

IVF and ICSI in combinationFollowing one IVF cycle with unexpected poor(


3/6

L.Hamberger et al

Sperm quality

IV F intennediate ICSI

ICSI/IVF(split cy cles)

Figure 1. Simplified flow schedule for choosing optimal fertilization technique depending on sperm quality (quantitative and/orqualitative disorders) and fertilization rate.

Table I. The non-existent, relative, and absolute indications for intracytoplasmic sperm injection (ICSI)IVF as first choice IVF and ICSI in combination ICSI as first choiceNormal sperm sample No or poor fertilization in first cycle No or poor fertilization in two IVF cycles

Less than 0.8X1 06 spermatozo a after preparation Epidid ymal/testicular spermatozoaSperm morphology < 5 % normal GlobozoospermiaAntisperm antibodies Immotile spermatozoa

Frozen-thawed spermatozoa with poorsurvivalPreimplantation genetic diagnosis

IVF = in-vitro fertilization.reports have now appeared in the literature con-cerning this indication (Bourne et al. 1995; Liuet al 1995; Trokoudes et al. 1995).

Patients with imm otile cilia syndrome frequentlyhave 100% immotile spermatozoa or only fewmotile spermatozoa and thus constitute anotherabsolute indication for ICSI. In this case a vitalstain should be performed in advance to evaluatethe chances of choosing a viable spermatozoonwhen performing the injection. The ICSI methodcan be combined with a hypo-osmotic swellingtest (HOS) which will help to select viable spermthat can be used directly for ICSI (Chida, 1995;Esteves et al. 1996). This procedure can also beperformed for testicular samples where often only

immotile spermatozoa are found. Other subgroupswhere ICSI should be chosen are those in whichfertilization is to be combined with preim plantationgenetic diagnosis (PGD) since the use of conven-tional IVF leaves numerous spermatozoa stuck inthe zona pellucida or in the perivitelline space.When blastomere biopsy is performed, suchspermatozoa may 'contaminate' the biopsy andthus give incorrect diagnosis.

Utilization of frozen-thawed spermatozoaCry preservation of ejacu lated sperm causes adecrease in sperm viability and motility, but thethawed spermatozoa can still in most cases be used

130


4/6

Indications for ICSIfor conventional IVF after thawing. In cases withextreme impairment of motility after freezing-thawing and in cases of initial poor sperm quality,ICSI is of course preferred. We, along with othergroups (Devroey et ah 1995; Hovatta et al. 1996;Holden et al. 1997), have found that spermatozoaobtained from the epididymis and from the testisusually survive well in the freezer and retaingood fertilizing potential after thawing. It is to berecommended that in all cases where spermatozoahave been isolated from the epididymis or fromthe testis, excess spermatozoa should be frozen foruse in later cycles. In such cases ICSI should ofcourse always be applied to achieve fertilization.In our programme we have found exceptionallyhigh fertilization and pregnancy rates using froze n-thawed epididymal spermatozoa. This may pos-sibly be due to changes in the membrane structureof the spermatozoon, which may facilitate itsdecondensation within the oocyte. This is currentlyunder investigation in our laboratory.

A 'good' epididymal sample can be frozen usinga protocol similar to that of an ejaculated sample,i.e. with glycerol or egg yolk. Cohen et al. (1997)have developed a method of freezing a very lownumber spermatozoa inside an empty zona pellu-cida, an elaborate but promising technique forextreme cases. Testicular biopsies can be frozeneither as tissue pieces, or after dissection andpreparation.

Future indicationsIt is important to remember that the indicationsfor ICSI should at present not be rigid. As moreexperience is gathered, new indications will appear,and old indications may well change. For example,Bertrandet al.(1995) found that the zona p ellucidaof fertilized oocytes in conventional IVF wassignificantly thinner than those of unfertilizedoocytes. A thick zona pellucida may thus sub-sequently become an indication for ICSI (possiblyin combination with assisted hatching). Anotherindication may be the acrosomal index of thesperm sample, i.e. the specific morphology of theacrosome (Menkveld et al. 1994 ).

Concluding remarksIn this short communication interest has beenfocused predominantly on various male factors

zona binding testsoocyte penetration tests

Figure 2. Cross-checking of fertility within the couple by useof both donor oocytes and donor sperm. Possible spermfactors can also be studied using e.g. zona binding tests onsalt-stored unfertilized oocytes, and oocyte penetration testsusing zona-free hamster oocytes.

where ICSI may be the method of choice. Themain advantage of this method is that the outcomeis not directly related to any of the three basicsemen parameters: the number of spermatozoa,their motility or their morphology (Nagy et al.1995).The maturation stage, the acrosome reaction,the binding to the zona pellucida and the fusionwith the oolemma are all bypassed. What is stillrequired is the deconden sation ofthespermatozooninside the oocyte and the activation of the oocyte.Failure of these even ts to occur are presumably duenot only to sperm factors, but also to oocyte factors.

Oocyte factors responsible for fertilization fail-ure with conventional IVF are presumably notinfrequent but are more difficult to demonstratewithout the use of some type of cross-fertilization(Figure 2). In many countries legal restrictionsmake such cross-fertilization impossible. It maystill be possible to study sperm binding to salt-stored unfertilized oocytes (Liu et al. 1989), whichcan give an indication as to whether an oocytefactor or sperm factors are responsible for problemsin the binding process.

Complete fertilization failure when using ICSIis very unusual, and in most cases is presumablydue to either failed oocyte activation or incom pletedecondensation of the spermatozoon (Sousa et al.1994; Flaherty et al. 1995). Again, this may bedue to either an oocyte factor or a sperm factor.The approach of splitting oocytes for IVF and

131


5/6

L.Hamberger etalICSI in the same cycle may both improve theclinical success rate with minimal increase inworkload, and also increase understanding of thereason for unsuccessful fertilization. Laboratorieswhere the experience of the ICSI technique islimited may well produce better results with con-ventional IVF in cases of e.g. moderate teratozoo-spermia, where the indication to use ICSI is onlyrelative. It therefore follows that the same guide-lines cannot be applied in all laboratories. Alsothe couples own opinion and economic aspectsmust be taken into account when advice is givenconcerning the optimal technique for treatment. Itis our impression that the enthusiasm raised by thegood results achieved with ICSI have presently ledto an uncritical overuse of this new technique.Until it is proven that ICSI does not introduce anyincreased risks for malformations and/or geneticdefects, it is our opinion that the indications forits use should be strict and that the techniqueshould be used only when properly indicated (TableI) . From the above presentation it is obvious thatindications for using ICSI may either be non-existent, relative or absolute.

cknowledgementsThis work was supported by grants from The SwedishMedical Research Council (no. 2873).

eferencesBertrand,E., Van Den Bergh,M. and Englert, Y. (1995)Does zona pellucida thickness influence thefertilization rate? Hum.Reprod. 10,1189-1193.Bourne,H., Liu, D.Y., Clark,G.N. and Baker, H.W.G.(1995) Normal fertilization and embryo developmentby intracytoplasmic sperm injection of round-headed

acrosomeless sperm.Fertil. Steril. 63,1329-1332.Chida, S. (1995) Immobilized and hyp o-osmotic swollenspermatozoa on intracytoplasmic sperm injection. J.Assist. Reprod.Genet. 12, 453-45 5.Cohen, J., Alikani, M., Maker, H.E. et al. (1991)Partial zona dissection or subzonal sperm insertion:microsurgical fertilization alternatives based onevaluation of sperm and embryo morphology. Fertil.Steril. 56,696-706.Cohen, J., Garrisi, J.G., Congedo-Ferrara, T.A. et al.(1997) Cryopreservation of single humanspermatozoa. Hum.Reprod. 12, 994-1001.Devroey, P.,Silber, S.,Nagy, Z. et al. (1995) Ongoingpregnancies and birth after intracytop lasmic sperm

injection with frozen-thawed epididymalspermatozoa. Hum.Reprod. 10,903-906.Esteves,S.C.,Sharma, S.C., Thomas A.J.and Agarwal,A. (1996) Suitability of the hypo-osmotic swellingtestforassessing the viab ilityof cryopreserved sperm.Fertil. Steril 66,798-804.Fishel, S. Timson, J., Lisi, F. andRinaldi, L. (1992)Evaluation of 225 patients undergoing subzonalinsemination for theprocurement of fertilization invitro. Fertil. Steril 57,840-849.Flaherty, S.P.,Payne, D., Swann, N.J. and M atthews,C D . (1995) Aetiology of failed and abnormalfertilization after intracytoplasmic sperm injection.Hum.Reprod. 10,2623-2629.Grow, D.R.,Oehninger, S., Seltman, H. et al. (1994)Sperm morphology as diagnosed by strict criteria:probing the impact of tertatozoospermia onfertilization rate and pregnancy outcome in a large

in vitro fertilization population. Fertil. Steril 62,559-567.Hamberger, L., Sjogren, A. and Lundin, K. (1995)Microfertilization techniques: choice of correctindications. Proceedings from IFFS Montpellier, pp.405^108.Holden, C.A.,Fuscaldo, G.F.,Jackson, P.et al.(1997)Frozen-thawed epididymal spermatozoa forintracytoplasmic sperm injection. Fertil. Steril 67,81-87.Hovatta, O., Foudila, T , Siegberg, R. et al. (1996)Pregnancy resulting from intracytoplasmic injection of

spermatozoa from a frozen-thawed biopsy specimen.Hum.Reprod. 11, 2472-2473 .Liu, D.Y., Clarke, G. N., Lopata, A. et al. (1989)A sperm-zona pellucida binding test and in vitrofertilization. Fertil. Steril 52,281-287.Liu, D.Y., Nagy, Z., Joris, H. et al (1995) Successfulfertilization and establishment of pregnancies afterintracytoplasmic sperm injection in patients withglobozoospermia. Hum.Reprod. 10,626-629.Lundin, K. and Hamberger, L. (1995) Antispermantibodies and assisted reproduction. Assist. Reprod.Rev. 5, 120-126.Lundin,K.,Sjogren,A., Nilsson,L. and Hamberger,L.(1994) Fertilization and pregnancy after intracyto-plasmic microinjection of acrosomeless spermatozoa.Fertil. Steril 62, 1266-1267.Lundin, K., Sjogren, A. and Hamberger, L. (1996)Reinsemination of one-day-old oocytes by use ofintracytoplasmic sperm injection. Fertil. Steril 66,118-121.Lundin, K., Soderlund, B. and Hamberger, L. (1997)Relationship between sperm mo rphology and the ratesof fertilization, pregnancy and spontaneous abortion inan IVF/ICSI programme.Hum.Reprod. 12, 101-106.Menkveld, R.,Rhemrev, J.,Franken,D.R. etal. (1994)Relationships between sperm acrosomal status, acrosin

132


6/6

activity, morphology (strict criteria) and fertilizationin vitro. Hum.Reprod. 9 (Suppl. 4), 99.Nagy, Z.P., Liu, J., Joris, H. et al. (1995) The result ofintracytoplasmic sperm injection is not related to anyof the three basic sperm parameters. Hum. Reprod.10, 1123-1129.Norman, R.J., Payne, D. and Matthews, C D . (1995)Pregnancy following intracytoplasmic injection (ICSI)of a single oocyte during a natural cycle. Hum.

Reprod. 10, 1626-1627.Ombelet, W., Fourie, F.leR., Vandeput, H. et al. (1994)Teratozoospermia and in-vitro fertilization: arandomized prospective study. Hum. Reprod. 9,1479-1484.Petersen, K., Gabrielsen, A., Mikkelsen, A.K1. andLindenberg, S. (1996) ICSI does not overcome anoocyte defect in previous fertilization faliure withconventional IVF and normal spermatozoa. 12th

Annual Meeting of the ESHRE Maastricht, Abstractno . 107.Silber, S.J., Nagy, Z.P., Liu, J.et al.(1994) Conventionalin-vitro fertilization versus intracytoplasmic sperminjection for patients requiring microsurgical spermaspiration. Hum.Reprod. 9 1705-1709.Sjogren, A., Lundin, K. and Hamberger, L. (1995)

Indications for ICSIIntracytoplasmic sperm injection of day old oocytesafter fertilization faliure. Hum.Reprod. 10, 974.Sousa, M. and Tesarik, J. (1994) Ultrastrucural analysisof fertilization failure after intracytoplasmic sperminjection. Hum.Reprod. 9 2374-2380.

Trokoudes, K.M., Danos, N. and Kalogirou, L. (1995)Pregnancy with spermatozoa from a globozoospermicman after intracytoplasmic sperm injection treatment.Hum. Reprod. 10, 880-882.Van Steirteghem, A., Liu, J., Joris, H., Nagy, Z. et al.(1993) Higher success rate by intracytoplasmic sperminjection than by subzonal insemination. Report of asecond series of 300 consecutive treatment cycles.Hum.Reprod. 8, 1055-1060.Vanderzwalmen, P., Barlow, P., Nijs, M. et al. (1992)Usefulness of partial dissection of the zona pellucidain a human in-vitro fertilization programme. Hum.

Reprod. 7, 537-544.Van Steirteghem, A., Nagy, P., Joris, H. et al. (1996)The developm ent of intracytoplasmic sperm injection.Hum. Reprod. 11 (Suppl. 1), 59-72.Wolf, J.Ph., Ducot, B., Kunstmann, J.M. et al. (1992)Influence of sperm parameters on outcome of subzonalinsemination in the case of previous IVF failure. Hum.

Reprod. 7, 1407-1413.

133

Date post:	04-Jun-2018
Category:	Documents
Upload:	arini-pramodavardhani-puteri
View:	219 times
Download:	0 times

Jurnal Trib Nyooooo

Documents