Effect of peritoneal fluid on sperm motility and velocity distribution using objective measurements

Dynamics of nitric oxide, altered follicular microenvironment, and oocyte quality in women with endometriosis

OBJECTIVE

To study follicular microenvironment in terms of free radical dynamics, oocyte quality, and assisted reproductive technology (ART) outcomes among women with (group A) and without (group B) endometriosis.

DESIGN

Prospective cohort study.

SETTING

University ART center.

PATIENT(S)

Women with and without endometriosis undergoing ART (n=28).

INTERVENTION(S)

Follicular fluid (FF), granulosa cells (GCs), immature oocytes (IOs), and ART data on sibling cohort oocytes in groups A and B were compared.

MAIN OUTCOME MEASURE(S)

ART live birth outcomes, maturation, and aging among in vitro matured (IVM) oocytes, nitrate levels in FF, and nitrotyrosine (NT) footprints and apoptosis in the GCs.

RESULT(S)

Clinical characteristics and ART live birth outcomes were no different between groups A and B. Women from group A had significantly lower peak serum E2 (2,068.8±244.6 pg/mL vs. 2,756.2±205.0 pg/mL) and higher apoptosis (80.0% vs. 22.2%) and NT staining (70.0% vs. 22.2%) in GCs compared with group B. Fewer IOs underwent IVM to MII (0.6±0.3) in group A compared with group B (1.4±0.2). IVM oocytes had significantly higher incidence of cortical granule loss (83.3% vs. 24.0%) and spindle disruption (66.7% vs. 16.0%) and higher zona pellucida dissolution timing (133.8±9.4 s vs. 90.5±5.8 s) in group A compared with group B. FF nitrate levels were significantly higher in women who failed to conceive in group A (478.2±43.1 nmol/L) compared with those that did conceive (173.3±19.0 nmol/L).

CONCLUSION(S)

Increased protein nitration, GC apoptosis, resistance to IVM, and oocyte aging indicate the involvement of oxidative dysregulation of NO in the pathophysiology of altered follicular milieu and poor oocyte quality in women with endometriosis.

Endometriosis and Inflammation in Infertility

A wealth of publications proposes that endometriosis and inflammation may have an unfavorable influence on fertility. A recent meta-analysis of assisted reproductive technologies demonstrated that, once confounding factors are controlled for, the pregnancy rate in women with endometriosis is approximately 50% of the rate of women with tubal factor infertility. Peritoneal fluid of women with endometriosis contains elevated amounts of macrophages and their secreted products, such as growth factors, cytokines, and angiogenic factors. Because reproductive organs are bathed in and thus will be influenced by peritoneal fluid, these proinflammatory mediators would affect various aspects of reproduction in women with endometriosis. Advanced stages of endometriosis may have easily understandable factors, such as distortion of the anatomy, causing infertility. On the other hand, in minimal or mild endometriosis mechanisms underlying reproductive failure are subtle and remain controversial. Recent reports suggest that inflammatory factors play a role in this endometriosis-associated reproductive failure. This review provides an overview of recent data on the effects of endometriosis-associated inflammation on fertility.

Modulation of human sperm function by peritoneal fluid

OBJECTIVE

To examine the effect of peritoneal fluid on various parameters of sperm function in vitro.

DESIGN

Prospective study.

SETTING

Basic research laboratory.

PATIENT(S)

Semen samples were obtained from normozoospermic volunteers (n = 43). Peritoneal fluids were aspirated laparoscopically from women with unexplained infertility (n = 14). Follicular fluid and oocytes were collected from patients undergoing IVF-ET.

INTERVENTION(S)

Sperm incubated under capacitating conditions were exposed to peritoneal fluid, and functional variables were evaluated in vitro.

MAIN OUTCOME MEASURE(S)

Sperm viability and motility, follicular fluid and calcium ionophore-induced acrosome reactions, protein tyrosine phosphorylation, expression of D-mannose binding sites, and ability of sperm to interact with zona pellucida.

RESULT(S)

Exposure of sperm to peritoneal fluid for up to 6 hours did not affect sperm viability or motility. Unlike follicular fluid, peritoneal fluid did not induce the acrosome reaction. Moreover, incubation of sperm with > or =20% v/v peritoneal fluid for 1 hour prevented the follicular fluid and the ionophore-induced acrosome reaction. Although treatment with peritoneal fluid allowed protein tyrosine phosphorylation during capacitation, it resulted in a significant decrease in the expression of D-mannose binding sites and sperm-zona pellucida binding.

CONCLUSION(S)

Peritoneal fluid maintains sperm survival and decreases sperm ability to respond to inducers of the acrosome reaction and bind to the zona pellucida in vitro, indicating that this fluid might modulate sperm function in vivo.

Influence of severe endometriosis on gene expression of vascular endothelial growth factor and interleukin-6 in granulosa cells from patients undergoing controlled ovarian hyperstimulation for in vitro fertilization-embryo transfer

OBJECTIVE

To evaluate how endometriosis affects expression of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) in granulosa cells.

DESIGN

Prospective study.

SETTING

IVF-ET program at Osaka Medical College.

PATIENT(S)

Seventeen patients with revised American Fertility Society stage IV endometriosis and 17 patients with tubal infertility and no endometriosis.

INTERVENTION(S)

Granulosa cells obtained at oocyte retrieval were examined for VEGF and IL-6 gene expression.

MAIN OUTCOME MEASURE(S)

Serum E(2) and P levels at hCG administration, number of oocytes, fertilization rate, high-quality embryo rate, and pregnancy rate, and expression of VEGF and IL-6 genes.

RESULT(S)

Total hMG and FSH levels were statistically significantly higher in patients with endometriosis; however, the number of retrieved oocytes and the fertilization rate were lower compared with patients with tubal infertility. Serum E(2) levels and expression of VEGF in patients with tubal infertility were statistically significantly higher than those in patients with endometriosis. Interleukin-6 gene expression did not differ between the groups.

CONCLUSION(S)

In severe endometriosis, lower VEGF gene expression in granulosa cells may adversely affect oocyte development and maturation.

Endometrial quality in infertile women with endometriosis

Several analyses in our infertility (IVF) and oocyte donation programs were carried out to gain clinical knowledge of the factors involved in the etiology of endometriosis-associated infertility. We first compared the IVF outcomes in women with tubal infertility and endometriosis. The results indicated that patients with endometriosis had a poorer IVF outcome in terms of reduced pregnancy rate per cycle, per transfer, and reduced implantation rate per embryo replaced. We then evaluated embryo development in vitro in women with and without endometriosis who underwent IVF and embryo replacement 72 hours after oocyte retrieval. We observed that compared to controls, patients with endometriosis had a significantly reduced number of blastomeres per embryo as well as an increased incidence of arrested embryos in vitro. In subsequent studies we compared fertility parameters in patients receiving donor oocytes. We noted that when donor oocytes came from patients without known endometriosis, embryo development and implantation rates were similar in patients with and without endometriosis. However, when the results of oocyte donation were classified according to the nature of the oocytes donated, patients who received embryos derived from oocytes from women with endometriotic ovaries showed a significantly reduced implantation rate compared to the controls. Taken together, these observations suggest that IVF in patients with endometriosis may be related to alterations within the oocyte, which, in turn, result in embryos of lower quality with a reduced ability to implant.

Effect of peritoneal fluid from women with endometriosis on implantation in the mouse model

OBJECTIVE

To investigate the potential role of peritoneal fluid (PF) from women with or without endometriosis in implantation in mice with use of the delayed implantation model.

DESIGN

A murine experimental model with markers of uterine receptivity and prospective comparison of the effects of human PF on implantation.

SETTING

Academic university and hospital program.

INTERVENTION(S)

PF collected from women with and without endometriosis was injected intraperitoneally into recently mated mice.

MAIN OUTCOME MEASURE(S)

Implantation sites were counted in treated and untreated animals, and the alphavbeta3 integrin was measured in the pregnant mouse uterus by immunohistochemistry with in situ hybridization. Leukemia inhibitory factor and the beta3 subunit of alphavbeta3 were measured by Northern blot during early pregnancy and after injections of PF.

RESULT(S)

Animals receiving PF from infertile women with endometriosis had a reduction in the number of implantation sites compared with animals that received PF from fertile women or from patients with recently treated endometriosis. In the mouse, expression of alphavbeta3 and leukemia inhibitory factor peaked at the time of implantation and was reduced by injections of human PF from infertile patients with endometriosis.

CONCLUSION(S)

Leukemia inhibitory factor and alphavbeta3 are coexpressed at the time of implantation in the mouse. PF from women with endometriosis has a detrimental effect on embryo implantation, perhaps by adversely affecting uterine receptivity.

Moderate and severe endometriosis is associated with alterations in the cell cycle of granulosa cells in patients undergoing in vitro fertilization and embryo transfer

OBJECTIVE

To determine whether folliculogenesis is impaired in patients with endometriosis.

DESIGN

Prospective study.

SETTING

Yamagata University School of Medicine, Yamagata, Japan.

PATIENT(S)

Thirty women participating in an IVF program.

INTERVENTION(S)

The patients were divided into four groups according to the cause of their infertility: tubal factor (T), n = 7; male factor (M), n = 7; idiopathic (I), n = 7; and endometriosis (E), n = 9. Granulosa cells were obtained from the follicular fluid of each patient and analyzed by flow cytometry.

MAIN OUTCOME MEASURE(S)

The percentage of granulosa cells in each cell-cycle stage.

RESULT(S)

The mean (+/- SD) rate of apoptosis in the granulosa cells obtained from the patients with endometriosis was the highest among the four groups (T = 11.7% +/- 3.3%; M = 5.6% +/- 3.8%; I = 9.6% +/- 5.1%; and E = 18.6% +/- 9.6%). The percentage of S-phase granulosa cells was significantly higher in the patients with endometriosis than in all the other patients combined (E = 12.5% +/- 6%; T + M + I = 9.3% +/- 2.9%). The percentage of G2/M-phase granulosa cells was significantly lower in the endometriosis group than in the other three groups combined (E = 2.3% +/- 2.5%; T + M + I = 4.6% +/- 2.1%).

CONCLUSION(S)

Endometriosis impairs the cell cycle in granulosa cells. This phenomenon may have a detrimental effect on folliculogenesis.

Peritoneal cellular immunity and endometriosis

PROBLEM

An immunologic basis has long been considered to be very important in the pathogenesis of endometriosis. Interactions of the peritoneal cells, which comprise macrophages, B cells, T cells, natural killer (NK) cells, and retrograde endometrial cells, are critical, but remain controversial, for exploring the pathogenesis of endometriosis.

METHOD OF STUDY

Accumulated data from the literature were reviewed, and our data were analyzed.

RESULTS

The data show that peritoneal macrophages are activated by the recurrent reflux of menstrual shedding. Humoral and local endometrial autoantibodies are detected in patients with endometriosis, but B cells are not quantitatively increased. There is decreased NK cell activity in the peritoneal cavity and peripheral blood, and this decreased activity may be related to the failure to clear out the ectopic endometrial tissue. Peritoneal T cells are predominant by Th1 inflammatory cells, and these cells are impaired because of a decrease in activation (especially HLA-DR+CD4+CD3+ population) and in the production of interleukin-2. Inflammatory cytokines such as interleukin-1, interleukin-6, and tumor necrosis factor-alpha are elevated in the peritoneal fluid of women with endometriosis.

CONCLUSIONS

The peritoneal NK and T lymphocytes are suppressed in women with endometriosis, but whether these immunologic deviations are the cause or the result of endometriosis is still unclear. Further studies are required to determine what role immunologic factors play in the pathophysiology of endometriosis.

Relationship between etiological factors and total motile sperm count in 350 infertile patients

The prevalence of different etiologic factors has been evaluated in 350 male patients consulting the same physician in an urban, ambulatory setting for primary or secondary infertility of more than 1 year. Environmental factors such as alcohol or drugs represented 12% of the etiologies, acquired diseases such as varicocele and prostatitis 40%, congenital diseases and primary testicular failure 16.2%, idiopathic cases 19.4%, and abnormality of sperm transport 7.4%. The severity of sperm alterations in the different etiologic categories was evaluated by the total motile sperm count per ejaculate (TMS) (normal > 16). The TMS was less than 5 in classical causes of male infertility such as testicular failure, endocrinopathy, cancer, or antisperm antibodies. It was more than 10 in controversial causes of infertility such as varicocele, prostatis, chlamydial infections, and professional exposure to heat. After treatment, there was a nonsignificant increase of the TMS in the latter cases. In cases of azoospermia of pituitary origin, the TMS was normalized by a hormonal treatment. In some cases of azoospermia of possible obstructive origin, sperm appeared in the ejaculate after diclofenac treatment. The utility of andrological investigation and treatment is discussed.

Computer-aided semen analysis: sperm concentration assessment by the Strömberg-Mika system

The scope of this study was to evaluate the accuracy, precision and specificity of the sperm concentration measurements by the Strömberg-Mika Cell Motion Analyser (SM-CMA). Our data show that the instrument generally underscores the sperm concentration and therefore the uncorrected measurements must be corrected by the operator using the 'mouse'-driven option. In terms of precision, the system appears to have an excellent internal precision whereas its repeatability is influenced by the sperm concentration, the sample's homogeneity and the correction of the raw data. In order to increase the system's repeatability, we suggest that sperm counts should be carried out in various fields of the counting chamber, and the mean of the corrected values be taken as representative of the sperm concentration in the ejaculate if the various measurements show a homogeneous (poissonian) distribution. The correction of the raw data with the 'mouse'-driven correction option was also shown to improve the system's reproducibility. Concerning specificity, our data evidenced that, without technical correction, the instrument failed to correctly classify certain spermatozoa as such, thereby grossly underscoring sperm counts. This finding was more evident at low sperm counts. Overall, the SM-CMA requires additional laboratory time but the corrected sperm counts are comparable to manual counts and semi-automated counts with the added option that it provides the andrologists with various motility characteristics not possible with the latter methodologies.

An elicited intraperitoneal inflammatory response has no effect on the establishment of pregnancy in the mouse

OBJECTIVE

To determine the impact of intraperitoneal inflammation on reproduction in the mouse.

DESIGN

The effect of an elicited sterile intraperitoneal inflammatory exudate and the passive intraperitoneal transfer of activated syngeneic leukocytes on mating efficiency and uterine implantations was evaluated in mice.

SETTING

Research laboratory.

INTERVENTIONS

Intraperitoneal injection of thioglycolate was used to elicit large numbers of activated peritoneal macrophages (mean 24.4 x 10(6) leukocytes/animal) in female CD-1 mice. The impact of this intraperitoneal exudate on mating efficiency and number of uterine horn implantations after gonadotropin-stimulated ovulation was determined. In separate experiments, the ovarian bursa present in this species was opened surgically to provide direct access of peritoneal constituents to the genital tract and the experiments repeated. Identical endpoints were evaluated in a third group of experiments using C3H/HEN syngeneic mice after passive transfer of 2, 5, and 10 x 10(6) similarly activated syngeneic peritoneal leukocytes.

RESULTS

Neither the elicitation of a peritoneal inflammatory exudate nor the passive transfer of up to 10 x 10(6) activated syngeneic peritoneal macrophages reduced the mating efficiency or the number of uterine implantations. Furthermore, surgically opening the ovarian bursa did not alter these results, although it was associated with anatomic distortion and lowered the number of implantations in all groups.

CONCLUSIONS

We could not confirm the previously published reports suggesting a profound adverse impact of intraperitoneal inflammation on reproduction in mice, even when providing direct continuity between the peritoneal cavity and the genital tract. Consequently, the usefulness of this model needs to be re-evaluated before considering it an adequate paradigm for evaluating potential mechanisms of infertility in women.

Endometriosis-associated infertility

Despite intense clinical interest and increasingly sophisticated diagnostic techniques, we know surprisingly little of the relationship between endometriosis and infertility or the mechanism of infertility in these couples. No therapy specifically directed toward the ectopic endometrial implants, medical or surgical, has been demonstrated to improve the likelihood of pregnancy for couples with endometriosis-associated infertility. This is consistent with the observation that, in the absence of mechanical distortion of the pelvic viscera, no therapy directed against the implants improves the likelihood of pregnancy in these couples. The reason for this lack of progress is most probably that the mechanism of infertility in these couples remains to be determined. At present, it would be more accurate to say that these couples have unexplained infertility. The most promising therapeutic approach is to treat women with endometriosis-associated infertility with a non-specific cycle fecundity enhancing technique. Typically this is one of the newer assisted reproductive technologies such as controlled ovarian hyperstimulation with intrauterine insemination of capacitated sperm. Since the fecundity of many of the women with endometriosis in the later reproductive years is rapidly declining, this may represent their most cost-effective option for establishing a pregnancy. Only with further effort directed towards determining the mechanisms of infertility in these couples will a more effective therapy be forthcoming.

Influence of peritoneal fluid from spontaneous and stimulated cycles on sperm motility in vitro

Peritoneal fluids (PFs) from spontaneous (n = 14) and gonadotrophin-stimulated cycles (n = 20) were obtained during diagnostic laparoscopy and gamete intrafallopian transfer (GIFT) procedures, respectively. The effects of these fluids on the linear component of sperm motility and on the percentage of motile spermatozoa were studied in vitro by objective motility assessments and compared to a control medium (B2-Ménézo). Overall, the two types of PFs were found to have rather similar effects on the motility parameters studied. However, the fluids from hormonally-stimulated cycles sustained motility better (i.e., sperm velocity and percentage of motile sperm) and in a rather constant manner as a function of time (narrower range distributions of the motility measurements). Furthermore, it was observed that under identical experimental conditions motility measurements depended not only on the type of PF used but also on the sperm sample. These results suggest that assisted reproduction procedures in which PF is the medium where the gametes eventually meet and interact, such as direct peritoneal insemination (DIPI) or peritoneal oocyte and sperm transfer (POST), could have different success rates if performed in spontaneous rather than in stimulated cycles. At the same time, our results may help to explain why different pregnancy rates were reported in different studies using DIP or POST.

Glucocorticoid treatment decreases sera embryotoxicity in endometriosis patients

OBJECTIVE

To investigate the effect of short-term glucocorticoid administration on embryotoxicity of sera from infertile patients with mild to moderate endometriosis.

DESIGN

Prospective longitudinal study.

SETTING, PATIENTS

Eight infertile patients with mild to moderate endometriosis and a control group of eight infertile patients with tubal infertility were selected on the basis of laparoscopic examination.

INTERVENTIONS

Basal (B) serum collection and day 1 (T1), day 3 (T2), day 6 (T3), and day 12 (T4) serum drawn after a 3-day glucocorticoid treatment in endometriosis patients.

MAIN OUTCOME MEASURE

Embryotoxicity of endometriosis sera, before and after glucocorticoid treatment, was investigated using a bioassay performed on two-cell mouse embryos. Interleukin 1 alpha (IL-1 alpha) and antismooth muscle, antimitochondrial, and antinuclear autoantibodies were also tested in these sera.

RESULTS

At 50% concentration, endometriosis serum is embryotoxic in comparison with control; 0% versus 61% of the embryos reached the blastocyst stage at 72 hours, respectively (basal versus control, P less than 0.001). However, this embryotoxicity significantly decreases 12 days after glucocorticoid treatment in comparison with untreated sera; 32.4% versus 0% of the embryos reached blastocyst stage at 72 hours, respectively (T4 versus basal, P less than 0.001), although they did not reach nontoxic levels (greater than 50%). Interleukin 1 alpha was undetectable in all samples analyzed. In endometriosis sera, antismooth muscle antibody was detected.

CONCLUSIONS

At 50% concentration, serum from infertile patients with minimal to moderate endometriosis appears to be embryotoxic to the in vitro development of two-cell mouse embryos. However, this embryotoxicity significantly decreases 12 days after a 3-day treatment with glucocorticoids.

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.

Human follicular fluid stimulates motility and velocity of washed human sperm in vitro

Human follicular fluid collected by laparoscopic oocyte pick-up during IVF was studied with a computer-assisted semen analyser to evaluate the effect of hFF on human sperm motility and velocity. Freshly ejaculated human sperm were washed with phosphate buffered saline and mixed with either PBS or hFF. At various incubation periods of time, hFF increased both sperm motility and velocity as compared with control (P less than 0.01). After incubation of sperm with hFF at 37 degrees C and 5% CO2 in air for 0, 1, 3, 6, and 12 h, the amplitude increase of motility were 49%, 77%, 330%, 2020%, and 3340% when individual control motility was considered to be 100%. The amplitude increase of curvilinear velocity were 43%, 51%, 67%, 152%, 278%, respectively. Comparison of the motility and velocity of the sperm treated with hFF between 0 and 12 h, showed that hFF preserved both motility and velocity in vitro (P less than 0.01). The stimulatory effect of hFF was retained after boiling at 100 degrees C for 30 min, or after being filtered through Amicon membrane cones, but it disappeared if the hFF had been pre-treated with chymotrypsin. However, hFF did not stimulate the motility and velocity of unwashed sperm in freshly ejaculated human semen. A non-dialyzable and heat-stable factor(s) with a molecular weight below 50,000 in hFF may improve and maintain the motility and velocity of washed human sperm. Whether this factor could be used to improve pregnancy rate in assisted reproduction awaits further investigation.

The stimulus responsible for the peritoneal fluid inflammation observed in infertile women with endometriosis

OBJECTIVE

We tested the hypothesis that menstrual debris from ectopic endometrium is the stimulus responsible for eliciting the peritoneal fluid (PF) inflammation observed in infertile women with endometriosis.

DESIGN, SETTING, PATIENTS

The extent of endometriosis was correlated with the PF volume and total PF cell count retrospectively in 135 infertile women with endometriosis.

RESULTS

The volume and total cell count were positively correlated, whereas the total cell count was negatively correlated with the extent of endometriosis. Despite a similar negative trend, no statistically significant correlation was noted between the volume and the extent of endometriosis. These relationships did not change when the data were reanalyzed deleting those pathological features contributing to the endometriosis score but not capable of producing intraperitoneal menstrual debris, i.e., adhesions and encapsulated ovarian endometriomas.

CONCLUSIONS

These findings indicate that menstrual debris from ectopic endometrium is probably not a major factor in the elicitation of the observed PF inflammation in infertile women with endometriosis and suggest an inverse relationship may exist between PF inflammation and the extent of endometriosis.

Human follicular fluid stimulates the motility of washed human sperm

Human follicular fluid (hFF) was collected by laparoscopic oocyte pickup during IVF to evaluate the effect of hFF on human sperm motility with a transmembrane migration method. Freshly ejaculated human sperm were washed with phosphate buffered saline (PBS) and mixed with either PBS or hFF. Amplitude of motility increases were 38% and 72% in washed fertile sperm and washed asthenozoospermic sperm when individual control motility was considered to be 100%. The stimulatory effect of hFF was lost when preheated at 100 degrees C for 30 minutes. hFF collected from mature follicles stimulated sperm motility better than that collected from intermediate or immature follicles. hFF did not stimulate the motility of unwashed sperm in freshly ejaculated human semen. A heat labile factor(s) in hFF may stimulate the motility of washed human sperm. Whether this factor could be used to improve the success rate of IVF and artificial insemination awaits further investigation.

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.