FERTILITY AND STERILlTY®

Copyright " 1997 American Society for Reproductive Medicine

Published by Elsevier Science Inc.

Vol. 68, No. 1, July 1997

Printed on acid-free paper in U. S . A.

The role of in vitro fertilization and intracytoplasmic sperm injectionin couples with unexplained infertility after failed intrauterineinsemination

Amparo Ruiz, M,D.*Jose Remohi, M.D.*Yolanda Minguez, Ph.D.*

Pedro P. Guanes, M.D.*Carlos Simon , M.D.*tAntonio Pellicer, M.D.*t+

Instituto Valenciano de Infertilidad, and Valencia University School of Medicine, Valencia, Spain

Objective: To determine an optimal insemination technique in patients undergoing IVF afterfailed lUI and the role of intracytoplasmic sperm injection (lCSI) in such cases.

Design: Prospective, randomized study in couples with unexplained infertility (n = 63) andmild endometriosis (n = 7) undergoing IVF after four failed lUI cycles. Sibling oocytes wererandomized into standard IVF or ICSI insemination according to the order of retrieval.

Setting: In vitro fertilization program at the Instituto Valenciano de Infertilidad, Valencia,Italy.

Patient(s): Seventy couples with unexplained infertility undergoing IVF aft er failing to con­ceive with controlled ovarian stimulation and lUI.

Intervention(s): In vitro fertilization and ICSI.Main Outcome Measure(s): Fertilization, cleavage, and embryo quality were compared in

IVF- and ICSI-inseminated oocytes.Result(s): There was no significant difference in fertilization rates between ICSI (60.4%) and

conventional IVF (54.0%). Similarly, there was no difference in embryo quality between bothgroups. There was no total fertilization failure in ICSI-inseminated oocytes , whereas 8 (11.4%)of 70 cases showed absence of fertilization when conventional IVF was used.

Conc1usion(s): Couples with unexplained infertility and mild endometriosis failing to con­ceive with lUI and undergoing IVF have an 11.4% chance of fertilization failure that can beovercome easily by using ICSI in at least some oocytes. ICSI, however, is not superior to IVFas an insemination technique in most cases . These data should be used in counseling pa­tients. (Fertil Sterilv 1997; 68:171-3. © 1997 by American Society for Reproductive Medi­cine.)

Key Words: Intracytoplasmic sperm injection, unexplained infertility, in vitro fertilization,endometriosis, failed fertilization

Intrauterine insemination, in combination withovarian stimulation with menotropins, has been in­troduced as an acceptable method for the treatmentof infertility of different causes including unex­plained infertility. Because a causal relationship be-

Received September 23, 1996; revised and accepted March 20,1997.

* Instituto Valenciano de Infertilidad.t Department of Pediatrics, Obstetrics and Gynecology, Valen­

cia University School of Medicine.:j: Reprint requests: Antonio Pellicer , M.D., Instituto Valenciano

de Infertilidad, Guardia Civil 23, Valencia 46020, Spain (FAX:346-3694735).

0015-0282/97/$17.00PH 80015-0282(97)00104-0

tween minimal and mild endometriosis and infertil­ity has not been demonstrated definitively, someclinicians (1) prefer to consider minimal endometrio­sis as a form of unexplained infertility as well.

Failure to conceive can be regarded as a problemof [1] gamete quality and interaction, [2] embryo de­velopment and transportation in the pre implanta­tion stages, or [3] implantation and subsequent de­velopment. The use of IVF is recommended not onlyfor therapeutic reasons, but also because of the pos­sibility oflearning about the reproductive process ina given couple. Specifically, reduced fertilization andcleavage rates have been documented in IVF cyclesperformed for unexplained infertility (2), suggesting

171

Table 1 Results of in Vitro Insemination of Sibling Oocyteswith Conventional IVF and ICSI*

ried out using the Statistical Package for Social Sci­ences (SPSS Inc., Chicago, IL).

IVF ICSI

gamete defects in such couples. In addition, thechances of total fertilization failure have been re­ported to be as high as 20% (3, 4) and may be system­atically repeated in subsequent cycles (3). Since theintroduction of intracytoplasmic sperm injection(ICSl) for the treatment of male infertility, clinicianshave had a powerful tool to overcome fertilizationproblems such as reduced or absent fertilization incouples with unexplained infertility. This study hasbeen designed prospectively to address two ques­tions: [1] the value of ICSI in couples with unex­plained infertility failing to conceive with standardlUI and [2] the possible role of ICSI so as to avoidfertilization failure in the first IVF attempt in suchcouples. To this end, ICSI and routine IVF have beenapplied randomly on sibling oocytes during the firstattempt of NF in couples with unexplained infer­tility.

Age(y)No. of oocytesNo. of oocytes per patientFertilization per inseminated oocyte (%)Fertilization per obtained oocyte (%)2 pronuclei patient (%)Complete fertilization failureNo. of embryosNo. of embryos per patientNo. of blastomeres per embryoDegree of fragmentation per embryo

*Values are means ± SEM.t p < 0.0001.tP < 0.01.

31.9 ± 0.4551

7.8 ± 0.454.0 ± 3.8t54.0 ± 3.549.4 ± 3.58 (11.4%)t

2653.8 ± 0.42.5 ± 0.81.3 ± 0.1

31.9 ± 0.4589 (490 MIl)

8.4 ± 0.478.4 ± 2.3t60.4 ± 3.657.5 ± 2.4

at309

4.4 ± 0.32.9 ± 0.11.2 ± 0.1

MATERIALS AND METHODS

Patients included in the present study were 70couples attending our artificial insemination pro­gram either because of unexplained infertility (n= 63) or mild endometriosis (n = 7), in whom concep­tion failed after four courses of treatment. The meanage ofthe females was 31.9 ± 0.4 years. Unexplainedinfertility was defined as a normal semen analysisaccording to the criteria of the World Health Organi­zation (5), including the absence of antisperm anti­bodies, and a normal hysterosalpingogram, lapa­roscopy, and postcoital test. Endometriosis wasdiagnosed by laparoscopy or laparotomy. After fourcycles of unsuccessful lUI with husband's sperm, thefemale partners were counseled to undergo an IVFtreatment cycle in which the retrieved oocytes wererandomly divided into two groups as they were ob­tained: odd numbers were microinjected, and evennumbers were inseminated by standard IVF. Theprotocol was approved by the Ethical Committee ofour institution, and informed consent was obtainedfrom all couples. End points of the study were tocheck normal and abnormal fertilization in vitro, aswell as embryo development and pregnancy rate(PR). The protocols for our standard IVF and ICSIprocedures have been published elsewhere (6). It isof interest to emphasize that ICSI was performedonly in metaphase II oocytes after appropriate re­moval of the cumulus. The degree of embryo frag­mentation was established in four different degrees,considering type I embryos as those with round andwell-shaped blastomeres without fragments.

Data were expressed as means ± SEM. Mann­Whitney's and Fisher's exact tests were employedfor comparison between groups. Significance was de­fined as P < 0.05. The statistical analysis was car-

172 Ruiz et al. Communications-in-brief

RESULTS

Table 1 shows that ICSI provided significantly (P< 0.0001) higher fertilization rates than did IVF perinseminated oocyte; however, fertilization rates perobtained oocyte were not different between groups,resulting in an equal number of embryos availablefor replacement. Similarly, the quality of the em­bryos obtained did not differ between groups. Com­plete fertilization failure using routine IVF was ob­served in 8 of 70 cases (11.4%) compared with zero(0170) in ICSI oocytes (P < 0.01).

The cases with fertilization failure employing IVFare further analyzed in Table 2. No difference be­tween groups was observed with regard to age, se­men characteristics, fertilization rates, and embryoquality.

A total of 38 replacements were performed usingembryos derived from ICSI. Eleven pregnancieswere recorded (28.9% PR per transfer). Two trans­fers were done with IVF-derived embryos withoutsuccess. Moreover, 29 replacements were performedwith embryos obtained using both inseminationtechniques. Ten pregnancies resulted (34.5% PR perreplacement).

DISCUSSION

The question addressed in our study was whetherICSI may be indicated in the first IVF attempt afterfailing to conceive with lUI. Our study has shownthat 8 of70 couples suffered fertilization failure withstandard IVF. In other words, 11.4% of the couplesundergoing IVF because of unexplained infertility(including mild endometriosis) (2), would probablyhave had no embryos for replacement if lCSl wouldnot have been employed. This rate is somehow lower

Fertility and Sterility"

than previously reported for a similar population (3,4). We do not believe that this percentage by itselfsubstantiates ICSI in all these cases, but such fig­ures should be remembered and used when counsel­ing patients about assisted reproductive techniques.

We further analyzed the cases with fertilizationfailure, using regular IVF to identify factors respon­sible for such observations. Neither the quality ofthe sperm sample nor the age and number of oocytesretrieved (which would indicate impaired oocytequality) were different between couples with andwithout IVF fertilization. Moreover, the probabilityof fertilization failure in a subsequent IVF attemptafter a failed cycle is as high as 22% (3). Thus, wefirmly believe that the data presented here may beuseful in giving appropriate information to infertilecouples because there is no possibility of predictingwhich couples are going to have fertilization failure.Once a failed cycle has occurred, however, ICSIshould be the method of choice in a second attempt.

The routine use of ICSI would be advocated if itstherapeutic role could be demonstrated. The assess­ment of the therapeutic value of ICSI in the firstattempt of IVF would need several clear end points:comparison of normal fertilization rates, embryoquality, and implantation rates. Implantation rateswere unfortunately not addressed in this study be­cause of the simultaneous transfer of embryos gener­ated by both treatments. Comparison of fertilizationrates initially showed significant differences wheninseminated oocytes were considered. The realpower of ICSI, however, in this particular situationhas to be analyzed starting with the total number of

IVF (+)

Table 2 Seminal Parameters and Results with ICSI,Comparing Cases With and Without Fertilization inTheir IVF-Inseminated Oocytes*

No. of cyclesAge (y)Sperm concentration (x 105

)

Progressive motility (%)Progressive motile spermatozoa (%)Normal spermatozoa (%)tNo. of oocytes per patientIVG inseminated ooytes per patientFertilization per patient (lCS!) (%)No. of embryos per patientNo. of blastomeres per embryoDegree of fragmentation per embryoPregnancy rate (%)

*Values are means ± SEM.t Kruger criteria.

6231.3 ± 0.459.8::: 4.638.1 ± 2.167.2::: 9.227.3 ::: 10.614.9::: 0.6

7.4::': 0.479.4::': 2.75.1::': 0.32.9::': 0.11.2::': 0.1

27.4

IVF (-)

832.0 ± 1.551.8 ± 10.434.1 ± 5.349.4 ± 18.825.2 ± 10.814.1 ± 0.66.8 ± 0.4

68.5 ± 8.55.1 ± 0.22.9 ± 0.41.4 ± 0.3

50.0

oocytes retrieved. Taking into account the immatureand degenerated oocytes discarded in ICSI proce­dures, the final number of two pronuclei-oocytes andembryos available for transfer was similar, indicat­ing no advantage ofICSI over standard IVF in casesof unexplained infertility. Similarly, the quality ofthe embryos obtained by both techniques did notdiffer as ascertained by the number of blastomeresdeveloped after 48 hours in culture and the degreeof fragmentation.

A similar study to the one presented here has beenpublished recently by Aboulghar et al. (4) on 22 cou­ples with unexplained infertility. Although thatstudy was based on lower numbers, the authorsreached similar conclusions in terms of fertilization.The rate of total fertilization failure in that study(22.7%) was higher than ours. The reason for thediscrepancy may be explained by the definition ofthe male factor. In fact, it has been shown that strictevaluation of semen in couples diagnosed as havingunexplained infertility rules out 50% of cases be­cause of sperm abnormalities (2).

In summary, the present study demonstrates thatICSI does not increase fertilization rates in coupleswith unexplained infertility undergoing IVF. It does,however, avoid the complete fertilization failureseen in 11.4% of these patients when treated by rou­tine NF.

REFERENCES

1. Weiner S, DeCherney AH, Polan ML. Human menopausalgonadotropins: a justifiable therapy in ovulatory women withlong-standing idiopathic infertility. Am J Obstet Gynecol1988; 158:111-7.

2. Navot D, Muasher SJ, Oehninger S, Liu HC, Veeck LL,Kreiner D, et al. The value of in vitro fertilization for thetreatment of unexplained infertility. Fertil Steril 1988;49:854-7.

3. Lipitz S, Rabinovici J, Ben-Shlomo I, Bider D, Ben-Rafael Z,Mashiach S, et al. Complete failure of fertilization in coupleswith unexplained infertility: implications for subsequent invitro fertilization cycles. Fertil Steril 1993;59:348-52.

4. Aboulghar MA, Mansour RT, Serour GI, Sattar MA, AminYM. Intracytoplasmic sperm injection and conventional invitro fertilization for sibling oocytes in cases of unexplainedinfertility and borderline semen. J Assisted Reprod Genet1996; 13:38-42.

5. World Health Organization. Laboratory manual for the ex­amination of human semen and semen cervical mucus inter­action. 3rd ed. New York: Cambridge University Press,1993:43-4.

6. Gil-Salom M, Minguez Y, Rubio C, Remohi J, Pellicer A. In­tracytoplasmic testicular sperm injection: an effective treat­ment for otherwise intractable obstructive azoospermia. JUroI1995;154:2074-7.

Vol. 68, No.1, July 1997 Ruiz et al. Communications-in-brief 173