Improved pregnancy rates and outcome with gamete intrafallopian transfer when follicular fluid is used as a sperm capacitation and gamete transfer medium

Intrafollicular insemination for the treatment of infertility in the dairy cow

Intrafollicular insemination (IFI) is based on direct introduction of a sperm suspension into a preovulatory follicle. To our knowledge, the first cases of IFI resulting in pregnancy of the cow are reported here. The experiment was performed on a dairy herd with low fertility during the warm season of the year. Following the sequence of estrus detection, one in three inseminations was intrafollicular (n = 17), whereas deposition of semen was performed into the uterine body (IUI) in the remaining cows (n = 33). Approximately 0.06 ml of a seminal dose containing five million spermatozoa (one quarter of a commercial seminal dose in a 0.25 ml French straw) was injected trans-vaginally into the preovulatory follicle in the IFI group. Four (23.5%) and 3 (9%) cows of the IFI and IUI groups, respectively, became pregnant. On days 8-11 post-insemination, ovulation failure was registered in 3 (18%) and in 4 (12%) cows of the IFI and IUI groups, respectively. Our results suggest that IFI could be used as an alternative procedure to the usual deposition of semen into the uterus in cows of low fertility.

Sperm motility stimulation and preservation with various concentrations of follicular fluid

PURPOSE

The purpose of this study is to evaluate the optimal concentrations of follicular fluid (FF) for sperm motility stimulation and preservation.

METHODS

Thirty normal semen samples and FF from women in an in vitro fertilization programme were used in an experiment. The semen was processed and incubated in Earle culture media with 20, 50, 80, and 100% FF (v/v) with controls. Sperm motility was evaluated and followed up for 48 h.

RESULTS

FF could stimulate progressive sperm motility at all concentrations and last for at least 12 h. However, at more than 50% v/v of FF, sperm demonstrated a rapid decline in progressive motility after 12 h of incubation compared to other concentrations and the control group.

CONCLUSION

FF can stimulate the sperm motility properly at not more than 50% (v/v) concentration.

Cumulus oophorus-associated glycodelin-C displaces sperm-bound glycodelin-A and -F and stimulates spermatozoa-zona pellucida binding

Spermatozoa have to swim through the oviduct and the cumulus oophorus before fertilization in vivo. In the oviduct, spermatozoa are exposed to glycodelin-A and -F that inhibit spermatozoa-zona pellucida binding. In this study, we determined whether these glycodelins would inhibit fertilization. The data showed that the spermatozoa without previous exposure to glycodelin-A and -F acquired glycodelin immunoreactivity during their passage through the cumulus oophorus. On the other hand, when glycodelin-A or -F-pretreated spermatozoa were exposed to the cumulus oophorus, the zona pellucida binding inhibitory activity of glycodelin-A and -F was not only removed, but the spermatozoa acquired enhanced zona pellucida binding ability. These actions of the cumulus oophorus were due to the presence of a cumulus isoform of glycodelin, designated as glycodelin-C. The cumulus cells could convert exogenous glycodelin-A and -F to glycodelin-C, which was then released into the surrounding medium. The protein core of glycodelin-C was identical to that in other glycodelin isoforms, as demonstrated by mass spectrum, peptide mapping, and affinity to anti-glycodelin antibody recognizing the protein core of glycodelin. In addition to having a smaller size and a higher isoelectric point, glycodelin-C also had lectin binding properties different from other isoforms. Glycodelin-C stimulated spermatozoazona pellucida binding in a dose-dependent manner, and it effectively displaced sperm-bound glycodelin-A and -F. In conclusion, the cumulus cells transform glycodelin-A and -F to glycodelin-C, which in turn removes the spermatozoazona binding inhibitory glycodelin isoforms and enhances the zona binding capacity of spermatozoa passing through the cumulus oophorus.

Cumulus cells reduce the spermatozoa-zona binding inhibitory activity of human follicular fluid

OBJECTIVE

To investigate the effects of human follicular fluid cultured with cumulus cells to inhibit the binding of spermatozoa to the zona pellucida of oocytes.

DESIGN

Controlled experimental laboratory study.

SETTING

University gynecology unit.

PATIENT(S)

Women undergoing assisted reproduction program and men visiting the subfertility clinics.

INTERVENTION(S)

Culture medium and human follicular fluid were used to culture cumulus cells in vitro for specified time periods.

MAIN OUTCOME MEASURE(S)

Zona binding capacity and motility of spermatozoa after incubation with cumulus cells treated culture medium or human follicular fluid.

RESULT(S)

Compared with the control medium, spent culture media after culturing cumulus cells for 3, 5, and 7 hours did not affect the motility and zona binding capacity of the treated spermatozoa. Significantly more spermatozoa treated with human follicular fluid that had been preincubated with cumulus cells for 5 and 7 hours bound onto hemizona in hemizona binding assay when compared with those preincubated in human follicular fluid without cumulus treatment. The hemizona index increased with the increase in the duration of cumulus cell treatment. Human follicular fluid with or without cumulus cells maintained sperm motility to similar extent for 3 hours.

CONCLUSION(S)

Cumulus cells reduced the inhibitory effect of human follicular fluid on spermatozoa-zona binding in vitro in a time-dependent manner.

Leukemia inhibitory factor in human reproduction

OBJECTIVE

To describe the clinical findings, expressions, interactions, and clinical implications of leukemia inhibitory factor (LIF) in human reproduction.

DESIGN

Review of published articles.

SETTING

Clinical development unit of biotechnology company.

INTERVENTION(S)

None.

RESULT(S)

In the endometrium, LIF is expressed in a menstrual cycle-dependent manner, with the highest level occurring at the time of implantation. LIF is also detected in uterine flushing, and its level is significantly lower in women with unexplained infertility. Likewise, endometrial explants derived from women with unexplained infertility showed reduced levels of LIF secretion. Binding of LIF to LIF receptor and gp130 activates signal transduction pathways. LIF receptor is expressed in endometrium, oocytes, and blastocysts. Cytotrophoblasts cultured in the presence of LIF differentiate toward an anchoring extravillous phenotype.

CONCLUSION(S)

On the basis of reports gathered from animal and human studies, LIF appears to play an important role in implantation and in the establishment of pregnancy.

Leukemia inhibitory factor in human reproduction

PROBLEM

Leukemia inhibitory factor (LIF) is a pleiotropic cytokine of the interleukin-6 family and has different biological actions in various tissue systems. Although named for its ability to inhibit proliferation of a myeloid leukemic cell line by inducing differentiation, it also regulates the growth and differentiation of embryonic stem cells, primordial germ cells, peripheral neurons, osteoblasts, adipocytes, and endothelial cells. LIF is crucial for successful implantation of the embryo in mice. Currently, there is an accumulation of data about the role of LIF in human reproduction.

METHOD OF STUDY

This review of the literature and of our studies focuses on the expression, regulation, and effects of LIF in the human endometrium, fallopian tube, and ovarian follicle.

RESULTS

Human endometrium expresses LIF in a menstrual cycle-dependent manner. Maximal expression is observed between days 19 and 25 of the menstrual cycle, coinciding with the time of implantation. Various cytokines and growth factors induce endometrial LIF expression in vitro. LIF receptor is expressed in endometrial tissue throughout the menstrual cycle and on human blastocysts in a stage-dependent manner. Affecting the trophoblast differentiation pathway toward the adhesive phenotype, LIF plays a role in implantation. LIF is also expressed and secreted by the epithelial cells of the fallopian tube. Its increased expression in the tubal stromal cell cultures by the inflammatory cytokines suggests a link between salpingitis and ectopic implantation in the tube. The rising follicular fluid LIF level around the time of ovulation indicates that LIF may play a role in ovulatory events, early embryonic development, and implantation.

CONCLUSIONS

There is growing evidence that LIF may be one of the entities that plays a role in human reproduction.

The detection of blood contamination in human follicular fluid

PURPOSE

The aim of this study was to compare the reliability of the methods conventionally used to identify low levels of blood contamination in human follicular fluid (hFF) as applicable in the clinical environment.

METHODS

Follicular fluid (n = 339) and plasma samples (n = 20) were collected from patients (n = 138) attending the Centre for Fertility Studies, HF Verwoerd Hospital, University of Pretoria, South Africa. hFF blood contamination was assessed by means of (a) visual inspection, (b) hematocrit (Hct), (c) spectrophotometric analysis, (d) spectrophotometric hemoglobin kit, and (e) Combur-9-test urine sticks.

RESULTS

(1) Neither hematocrit nor spectrophotometry provided reliable detection at low levels of blood contamination. (2) Visual inspection presented with a better discriminatory ability than either Hct or spectrophotometry. (3) Combur-9-test sticks identified up to 50% of blood-contaminated fluids. (4) Spectrophotometrically determined hemoglobin levels presented with weak discriminatory abilities for detecting blood-contaminated fluids.

CONCLUSIONS

Visual inspection as performed in this study provides a fast and relatively reliable method for the determination of blood-contaminated hFFs. In a laboratory environment, however, it would be recommended that a combination of visual inspection, Hct, and spectrophotometric evaluation be employed for the selection of blood-free fluids.

Relationship between anticomplement in seminal plasma and complement in follicular fluid associated with outcome in an in vitro fertilization program

PURPOSE

The study was conducted to evaluate levels of anticomplement in seminal plasma and levels of complement in follicular fluid, in correlation with fertilization and pregnancy rate after in vitro fertilization and intracytoplasmic sperm injection programs.

MATERIALS AND METHODS

Anticomplement levels were determined in 70 couples undergoing in vitro fertilization therapy. In 15 of these couples, complement levels were measured. Anticomplement and complement levels were also determined in an additional 21 couples (apart from the 70 couples) undergoing intracytoplasmic sperm injection treatment.

RESULTS

A correlation was found between fertilization rate and anticomplement levels in the seminal plasma (r = 0.4, P < 0.01) after standard in vitro fertilization. No correlation was found in the intracytoplasmic sperm injection group, or observed between complement levels and any parameter examined in both groups. Pregnancy occurred only in those couples with an anticomplement:complement ratio below 0.49.

CONCLUSIONS

Determination of anticomplement and complement levels may contribute to the assessment of a successful outcome of in vitro fertilization/intracytoplasmic sperm injection.

Appraisal of gamete intrafallopian transfer

OBJECTIVE

To collect results of gamete intrafallopian transfer on a large scale in order to compare treatment indications, results, and factors which influence the success rates; to evaluate whether gamete intrafallopian transfer is well-established and what the real place of this procedure is among other assisted reproduction techniques.

DESIGN

Data relating to gamete intrafallopian transfer were collected from World Reports, national registries of different countries and meta-analysis of medical publications during the years 1986-1991.

SUBJECT

Official registries reported 47,200 treatment cycles and 18,759 treatment cycles were analysed from ten medical publications.

RESULTS

The procedure accounts for 13.5% of all assisted reproduction techniques but its popularity varies significantly among countries. The same indications for gamete intrafallopian transfer are followed by all countries, but great differences exist with regard to the proportional share of each etiology. Also, the share has changed considerably over the years. TREATMENT OUTCOME: 10,667 clinical pregnancies were reported which represent 24% of treatment cycles and 29% of ovum pick-up. The live birth rate was 23.3%; abortion rate, 22%; and ectopic pregnancy rate, 5.5%. The stillbirth rate was 2.3% and the malformation rate was 2.8%, not confined to specific organs or systems. There were 19.5% twins, 4.6% triplets and 0.3% quadruplets or more. The number of transferred oocytes influenced pregnancy rates: 28% for transfer of four oocytes and only 10% following transfer of one oocyte. The cause of infertility might influence the results and the poorest results are obtained for male factor infertility. In most cases correlation of success rates reported by leading units through medical publications closely resembles the overall national registries results. Indications for this treatment were broadened over the years, but its role among other assisted reproduction technologies is not agreed upon, especially for male factor and unexplained infertility.

CONCLUSIONS

Gamete intrafallopian transfer carries an overall higher pregnancy rate than in vitro fertilization. Quality control by professional or public associations should be established and more research employed over indications for treatment and results in order to establish when GIFT is the treatment of choice and when other modes of treatment should be preferred.

Subtle tubal abnormalities adversely affect gamete intrafallopian transfer outcome in women with endometriosis

OBJECTIVES

To evaluate prospectively the impact of subtle tubal disorders on GIFT pregnancy rates in women with pelvic endometriosis.

DESIGN

A prospective comparison of pregnancy rates in different stages of endometriosis while controlling for the presence of tubal abnormalities.

INTERVENTIONS

A total of 146 patients with endometriosis underwent 201 GIFT procedures. During laparoscopy special attention was brought to the fallopian tubes and any anatomical disorders were recorded. Tubal abnormalities included tubal sacculations, diverticulae, convolutions, phimosis, fimbrial agglutination, and peritubal adhesions. Best tube was considered in the final analysis.

RESULTS

The presence of tubal abnormalities significantly lowered the pregnancy rates in all stages of endometriosis. When we controlled for age, semen characteristics, number of mature oocytes transferred, and tubal status, the extent of anatomical tubal disorders was the most important prognostic factor in determining pregnancy outcome.

CONCLUSION

The extent of tubal abnormalities rather than the stage of endometriosis seems to be an important prognostic factor in determining GIFT pregnancy rates. Couples should be counseled accordingly and accurate prognostic parameters should be explained before enrollment in a GIFT program.

Association between human in vitro fertilization rate and pregnancy outcome: a possible involvement of spermatozoal quality in subsequent embryonic viability

A conventional view of mammalian fertilization is that the active component of the process: the spermatozoon, by virtue of its progressive motility and acrosomal enzymes, penetrates an otherwise passive oocyte. This concept has placed bias on spermatozoal normality as largely determining the outcome of fertilization; once this has been achieved then the contribution of the spermatozoon is often forgotten, and attention switches to the maternally derived "blue-print" for early embryonic development. Paternal genomic contribution is known to start at the eight-cell stage in the human, but this is usually after the time when early cleavage stage (2 to 8-cell stage) embryos are replaced in human assisted reproductive technologies (ART) procedures such as in vitro fertilization and embryo transfer (IVF-ET). Hence, fundamental abnormal contributions to embryogenesis derived from the fertilizing spermatozoon have often been ignored. Human IVF-ET has permitted far greater powers of analysis of the fertilization event, and fertilization success appears to be determined in such a system by three main factors: spermatozoal quality, oocyte quality, and quality of in vitro culture conditions (the gamete environment). If the second two factors are more carefully controlled than the first, as is the usual emphasis in routine human IVF practice, then any large variation in fertilization rates that are also significantly related to embryonic viability and ultimately pregnancy outcome, may be thought to be more directly associated with original quality of the fertilizing spermatozoon. An analysis of results of 758 IVF cases provides preliminary evidence to show that there is a close association between human in vitro fertilization rate and subsequent embryo viability following replacement. In accepting this hypothesis as a possibility, we should drastically change our attitude from one of the spermatozoon as a robust, simple initiator of embryonic development, and embrace the idea of the vulnerability of such germ cells both during and after their production, and how detrimental influences on this might profoundly affect embryogenesis after successful fertilization.

Effect of follicular fluid on the kinetics of human sperm acrosome reaction in vitro

The purpose of the present study was to evaluate the kinetics of human sperm acrosome reaction in vitro using the triple stain technique. Acrosome reaction was studied in sperm samples from 16 fertile men 2, 6, and 9 h after ejaculation, following incubation in culture medium (CM; Ham's F-10), with a mixture of CM and follicular fluid (FF), or with FF only. Incubation of sperm samples without the influence of any medium served as control. The highest proportion of living acrosome-reacted sperm after a 2-h incubation period occurred in samples incubated with FF (18%), followed by samples incubated with the mixture (15.2%), and then with CM (11.8%). The proportion of living sperm that had undergone the acrosome reaction in the control group was significantly lower (5.7%, p < 0.05). After 6 h of incubation, live acrosome-reacted sperm in FF had increased to 39%, in the mixture to 35.5%, and in CM to 30.5%, whereas in the control group the increase was only 6.3% (p < 0.05). After 9 h of incubation, the percentage of living reacted sperm showed a decline compared with the percentage at 6 h. This decline was greater in samples incubated with FF (from 39 to 19.8%) than in samples incubated with the mixture (from 35.5 to 23.6%). Samples incubated in CM only showed a small decrease from 30.5 to 28.4%, while in the control group this percentage decreased from 6.3 to 2.3%. In conclusion, incubation of sperm in suitable media favorably influences the acrosome reaction, inducing an increase in the percentage of live acrosome-reacted sperm.(ABSTRACT TRUNCATED AT 250 WORDS)

Infertility treatment: from cookery to science. The epidemiology of randomised controlled trials

OBJECTIVES

To review the epidemiology of published randomised controlled trials in infertility treatment over the last 25 years, with special emphasis on the number and quality of trials.

DESIGN

Computer literature review by MEDLINE backed up by a manual search of 41 journals. Each trial was classified according to the methodology described and quality criteria. The results were recorded in a computer database. Odds ratios (OR) and confidence intervals (CI) were calculated where the data were sufficient.

SUBJECTS

Couples suffering from primary or secondary infertility. The trials studied 33,761 patients overall.

SETTING

Institute of Epidemiology and Health Services Research, Leeds.

RESULTS

Five hundred and one randomised trials in male and female infertility treatment were identified between 1966 and 1990. Pregnancy was an outcome in 291 (58%) and these were the subject of detailed analysis. Two hundred and twenty-four (77%) and 67 (23%) 'pregnancy trials' were concerned, respectively, with female and male infertility. Four per cent of the trials were preceded by a sample size calculation, and the average sample size was 96 patients (range 5-933); 700 patients per group would be required to demonstrate plausible success rates for most treatments. The method of randomisation was unstated or pseudo-randomised in 206 (71%) of trials where pregnancy was an outcome. Only 29 (5.8%) of studies were multicentre. The method of confirmation of pregnancy was omitted for 70% of papers. Cross-over design was used in 103 (21%) of cases. Meta-analysis is possible for selected topics such as the use of anti-oestrogens in idiopathic oligospermia and unexplained female infertility. Eight cases of double reporting were identified.

CONCLUSIONS

Trials using randomised methodology were relatively few in comparison with other branches of medicine, although their use is important in the evaluation of treatment for infertility as treatment-independent pregnancy is common. It was encouraging to note that an exponential increase in the use of this methodology occurred during the last three years, especially in association with assisted conception techniques, and meta-analysis has become possible for selected topics. However, many trials suffer from an unrealistically small sample size, inappropriate use of cross-over design or pseudo-randomisation. The trend towards properly controlled studies should be encouraged but these studies should be of improved quality and organised on a multicentre or even international basis.

Microsurgical aspiration of sperm from the epididymis: a mobile program

We report data from 25 microsurgical aspirations of the epididymis on 22 men. There were 14 men with congenital absence of the vas, 6 with failed vasoepididymostomy, 1 with adult cystic fibrosis and 1 with a childhood hernia repair. The specimens were used for assisted reproductive technologies, including in vitro fertilization and tubal embryo transfer. The protocol for aspiration, ovulation induction and sperm processing evolved during the course of these studies, and the patients were classified into 2 groups on the basis of methodology. Seventeen procedures were performed for the in-house in vitro fertilization team but 8 other procedures were done for nearby in vitro fertilization centers, and the final prepared sperm samples were transported as part of our mobile program. Group 1 patients underwent standard aspiration techniques, standard ovulation induction and sperm processing by wash and swim up. Among this group there were no fertilizations or pregnancies with 8 in-house and 2 transported specimens. Group 2 patients had leuprolide suppression before ovulation induction, direct intratubular aspiration and a complex sperm preparation, including pentoxifylline stimulation, mini-Percoll filtration and incubation with human follicular fluid. Among this group there were 2 fertilizations and 1 pregnancy with 9 in-house cases, and 3 fertilizations and 2 pregnancies with 6 transported specimens. These results suggest that a mobile program for microsurgical aspirations of sperm from the epididymis and in vitro fertilization or tubal embryo transfer is feasible within the framework of a strict protocol.

Modification of human sperm function by human follicular fluid: a review

This review assesses whether human follicular fluid (hFF) is able to modify human sperm function in vitro. Addition of hFF has been found to stimulate the motility of washed human spermatozoa, to increase the percentage of hyperactivated spermatozoa, to induce the acrosome reaction, to attract spermatozoa to the site of fertilization and to facilitate penetration of the oocyte by spermatozoa. It is possible that hFF could provide a favourable environment around the oocyte for fertilization by spermatozoa. Inclusion of hFF in gamete transfer medium may also improve the success rate of assisted reproduction technology. Purification of individual components in hFF which modify different aspects of sperm function awaits further investigation.

The contribution of a hidden male factor to unexplained infertility

OBJECTIVE

To assess sperm function in patients with unexplained infertility in comparison with normal fertile men.

DESIGN

Prospective study.

SETTING

Infertility outpatient clinic and donor insemination program, University Department of Obstetrics and Gynecology at the Jessop Hospital for Women, Sheffield, United Kingdom.

PATIENTS

Nineteen patients with unexplained infertility and nineteen normal fertile men from a donor insemination program.

MAIN OUTCOME MEASURES

Monitoring of reactive oxygen species generation; computerized assessment of the hyperactivated motility pattern of the spermatozoa under capacitating conditions, with and without the addition of follicular fluid (FF); evaluation of sperm-zona pellucida (ZP) binding.

RESULTS

Reactive oxygen species generation was not significantly different between the study and control group. Follicular fluid-induced hyperactivation (HA) was significantly lower in patients with unexplained infertility than in the donors, but no difference was found comparing spontaneous HA (without FF) between the two groups. Follicular fluid-induced HA was completely absent in 39% of infertile men and only one fertile man. A low sperm-ZP binding ratio (< or = 0.3) was observed in 28% (5/18) of patients with unexplained infertility. In all, nine infertile men (47%) had 0% FF-induced HA and/or low sperm-ZP binding ratio.

CONCLUSIONS

Assessing FF-induced HA and sperm-ZP binding may have clinical significance in distinguishing a subgroup of men with unexplained infertility with sperm function abnormalities in which the fertilizing capacity of the spermatozoa might be reduced. These patients cannot be identified by the conventional semen analysis. Both tests may also be useful in planning the appropriate treatment for couples with unexplained infertility.

Intrafollicular insemination for male factor infertility

Intrafollicular insemination is a promising new development that may have a major impact on ART, notably in the treatment of male factor infertility. Reported is the first successful intrafollicular insemination in the United States and the first successful intrafollicular insemination for male factor infertility. Although the results are encouraging, further investigations are currently underway to critically evaluate intrafollicular insemination.

Effect of volumetric mixtures of peritoneal and follicular fluid from the same woman on sperm motility and acrosomal reactivity in vitro

OBJECTIVE

To study the effect of peritoneal (PF) and follicular fluids (FF from the same woman) as well as of given volumetric combinations thereof on sperm motility and acrosomal reactivity.

DESIGN

Prospective. Peritoneal fluid and FF were incubated separately or in given volumetric combinations (PF/FF = 100/0, 75/25, 50/50, 25/75, 0/100; vol/vol) with swim-up sperm suspensions.

SETTING

In vitro fertilization and general infertility clinic and laboratories.

PATIENTS, PARTICIPANTS

Women participants of the gamete intrafallopian transfer program (motility study, n = 20; acrosomal reaction study, n = 14). Sperm donors of the artificial insemination program and men with given sperm parameters.

INTERVENTIONS

Hormonal stimulation. Laparoscopy.

MAIN OUTCOME MEASURES

Progressive velocity and percentage of motile gametes measured with multiple-exposure photography. Acrosomal reactivity measured by an immunofluorescent technique.

RESULTS

Follicular fluid always influenced progressive motility and also sustained the number of motile gametes, as function of time, better than PF or the PF/FF mixtures (P less than 0.05). The acrosomal reactivity of sperm incubated in the various PF/FF combinations was low; after 5 hours only the FF-sperm suspensions showed a significant enhancement of acrosomally reacted gametes.

CONCLUSION

At ovulation, FF transmit positive (motility- and acrosomal reactivity-enhancing) signals to sperm, whereas PF may transmit positive, neutral, or negative signals (noise signals). The volumetric combination of FF and PF in the tubal environment, which may differ from cycle to cycle and from woman to woman, could therefore result in synergic (or antagonistic) effects on the sperm fertility potential.

Comparative study on the use of human follicular fluid or egg yolk medium to enhance the performance of human sperm in the zona-free hamster oocyte penetration assay

A prospective study was conducted on 61 unselected semen samples from infertile patients to compare the efficacy of human follicular fluid (hFF) or TEST-egg yolk medium treatment in enhancing sperm performance in the zona-free hamster oocyte penetration (HOP) test. Both hFF and TEST-egg yolk enhanced penetration scores significantly in the HOP test in comparison with the control swim-up sperm preparation. The TEST-egg yolk medium treatment, however, exhibited the highest penetration scores, and there were higher percentages of preparations passing the 10 or 20% penetration rate cut-off point with sperm exposed to the TEST-egg yolk medium than those exposed to hFF. These results indicate that modification of the original HOP-test protocol by incorporation of TEST-egg yolk medium gives a greatly increased penetration rate when compared to the addition of hFF in such a system.

Follicular fluid enhances sperm motility and velocity in vitro

Forty-three follicular fluids (FFs) obtained during laparoscopy were tested in vitro for their effect(s) on sperm motility using gametes obtained by the swim-up procedure. Both the proportion of motile sperm and the velocity distribution patterns were evaluated as function of time by multiple-exposure photography technique. At the various incubation periods considered, all FFs maintained or then enhanced sperm motility as compared with the paired control suspension incubated with a sperm survival medium. The results of the sperm contact test for FFs from women who achieved pregnancy versus FFs from women who remained infertile were not significantly different for both parameters measured. Comparing these with our previously reported results, we may hypothesize that FF released at ovulation into the peritoneal cavity may counteract some sperm-immobilizing effect of peritoneal fluid, thereby increasing the fertility potential of the male gametes.