Benign prostatic hyperplasia (BPH) affects more than 95% of intact male dogs, yet most remain asymptomatic until prostatic enlargement causes clinical signs. Standardised assessment of BPH severity is therefore needed to improve clinical decision-making and enable comparable research outcomes. This study aimed to investigate current diagnostic and therapeutic approaches to canine BPH and to develop and assess a web-based application implementing the Zambelli Symptom Index (ZSI), an established symptom-based scoring system for BPH severity. A voluntary questionnaire was completed by veterinary practitioners to assess current clinical practice, and agreement between the web-based and reference paper-based ZSI classifications was evaluated. The survey revealed considerable variability in the recognition of clinical signs, assessment of BPH severity, and selection of treatment strategies, despite broad agreement on the diagnostic value of ultrasonography and the need for further investigation of prostatic enlargement. The web-based ZSI showed very high agreement with the reference classification. These findings demonstrate that the ZSI can be implemented digitally without materially affecting severity classification. The web-based tool may improve the standardisation and reproducibility of BPH assessment in clinical practice and research. Further studies are warranted to evaluate interobserver variability, clinical validity, and responsiveness to treatment.

The buffalo is an important species in many regions of the world, particularly in Asia, Africa and parts of Europe. Among the various species of buffalo, the water buffalo (Bubalus bubalis) is the most widespread, and it is well-known for its ability to thrive in wet and humid environments. In Europe, Italy is one of the leading producers of buffalo milk, and is particularly renowned for the production of Mozzarella di Bufala, a cheese made from the milk of water buffalo. Scientific knowledge on applied physiology, health, husbandry and reproduction in buffalo remains limited. This may be partly due to the fact that the species has historically been of greatest economic importance in regions where production systems are predominantly traditional and research investment has been limited. More recently, research has increasingly focused on production and feeding strategies and breeding practices. In addition, much of the research on the reproductive biology and management has concentered on the female buffalo, with particular emphasis on seasonality, oestruses detection and induction, whereas relatively little attention has been paid to male reproduction.This review discusses the reproductive physiology and behaviour of the male domestic buffalo in relation to differences in management and environmental conditions under which the species is reared, with a particular focus on the Italian Mediterranean buffalo breed (IMB).

This work sought to test the positive effect of red LED light on frozen bovine sperm resistance to thawing in suboptimal conditions. Moreover, a preliminary study explores whether this improvement could have any repercussions on in vivo fertilizing ability. Thus, frozen bull semen straws (n = 16) were thawed (a) with irradiation for 5 min at 20 °C (2 min light, 1 min darkness, 2 min light; PHOTO); (b) without irradiation for 5 min at 20 °C (ET); or (c) through immersion into a water bath at 38 °C for 40 s as standard control (CONTROL). Sperm quality and preliminary, purely descriptive AI trials were performed. The PHOTO samples demonstrated significantly (p < 0.05) improved percentages of intact acrosomes, progressive motility, DNA condensation and fragmentation, and viable sperm with high ROS/superoxides. The viability of PHOTO samples decreased significantly (p < 0.05) when compared with the ET ones. Overall results of both the PHOTO and ET samples were poorer than those of the CONTROL. Otherwise, the PHOTO straws yielded greater pregnancy rates (64.0% vs. 49.4% in CONTROL) when evaluated at two different farms. The results suggest that irradiating cryopreserved bovine sperm during thawing in suboptimal conditions could improve AI pregnancy rates, although more in vivo studies are needed to support this conclusion.

Dry storage at room temperature (RT) could simplify spermatozoa banking. Here, we explored DNA stability and in vitro and in vivo development of embryos derived from vacuum-dried encapsulated (VDE) ram spermatozoa stored for four years or after accelerated aging. While some genomic damage was detected at time 0, DNA fragmentation increased from 3.32 ± 3 % (time 0) to 37.64 ± 4 % (4 years). A decrease in blastocyst rate was observed after four years of storage and 6.7 years of simulated storage (10.2 % and 9 % versus 13.16 % at time 0). Embryo quality, assessed based on Cdx2 and Inf-τ gene expression, declined over time. Only two of the 23 embryos transferred into synchronized ewes were implanted but were lost by day 40. In conclusion, dry spermatozoa generated blastocysts after four years of RT storage, but their post-implantation development was impaired. Optimization of the water extraction and storage conditions could better preserve the spermatozoa's DNA integrity, resulting in improved embryo quality, compatible with development to term.

Extracellular vesicles (EVs), membrane nanoparticles (30-to-1000 nm diameter) secreted and released by most of the body functional cells, have emerged as powerful cell-to-cell messengers transferring their bioactive cargo (proteins, lipids, and nucleic acids) from donor to recipient cells. The promising potential utility of EVs as both noninvasive biomarkers and therapeutic carriers for several pathologies, including some types of cancers, has attracted increasing scientific interest. EVs can be found in all body biofluids, including seminal plasma, a complex fluid consisting mainly of a mixture of secretions of the epididymis and accessory sex glands. Seminal EVs are involved in modulating both sperm physiological processes and immune environment of the internal female genital tract, thus playing an essential indirect role in fertilization and embryo development. Seminal plasma, alike other biofluids, contains a heterogenous population of EV-subsets. However, the lack of consensus on the most accurate procedure for isolating EV-subsets has led to a poor definition of their composition/function. Currently, size exclusion chromatography (SEC), a size-selective separation method, is one of the most promising EV-isolation procedures, allowing the isolation of EVs from biological fluids in a purer, easier, cheaper, and more scalable way compared to other alternative isolation procedures. This chapter reports a SEC-based protocol, combined with differential centrifugation and ultrafiltration, to isolate two subsets of seminal EVs differing in size (large and small EVs) in the ejaculate of pigs, a livestock species of great productive interest and an outstanding animal model for human reproduction.

Nanoplastics (NP) accumulation in biological tissues and their adverse effects on fertility through inflammatory and oxidative stress responses have recently been described as consequences of global plastic pollution. However, little is known about the impact of NP on gametes. This study aimed to assess the internalization of NP and their effects on mature equine spermatozoa. Frozen-thawed ejaculates from five stallions were divided into untreated control (CTR) and samples supplemented with different concentrations (10, 50, 100 and 200 μg/mL) of 30 nm polystyrene NP. At baseline (T0), and after 1 (T1) and 3 h (T3) of incubation at 38 °C, sperm viability, mitochondrial activity, and intracellular ROS were evaluated by flow cytometry, while sperm motility was assessed using a CASA system. NP internalization was analyzed by confocal microscopy and flow cytometry using fluorescent NP. Results showed that NP were internalized by live spermatozoa, accumulating in the post-acrosomal and/or the mid piece region. NP exposure led to reduced sperm viability (CTR T1: 50.7 ± 14.0 % vs 200 μg/mL T1: 36.6 ± 11.8 %, p<0.05), decreased mitochondrial activity (CTR T1: 35.4 ± 15.8 % vs 200 μg/mL T1: 16.3 ± 14.0 %, p<0.001), and increase proportions of live sperm with high intracellular O2-· levels (CTR T1: 39.0 ± 10.1 % vs 200 μg/mL T1: 47.3 ± 11.0 %, p<0.05). These results allow us to conclude that equine sperm quality may be compromised by nanoplastics internalization, which pre-eminently impairs mitochondrial activity. This research furnishes some bases for further studies on the potential implications of NP exposure for fertility.

Seminal plasma composition has important role in sperm functionality and its freezability. The objective of this study was to test the hypothesis that seminal plasma (SP) oxidative status and metabolome are associated with fresh semen characteristics and freezability of bull sperm. To accomplish this objective, oxidative status markers and metabolome of SP of ejaculates obtained from 20 Holstein bulls (3 for each bull) were analyzed using spectrophotometry and nuclear magnetic resonance (1H NMR). The ejaculates were classified into higher motility fresh semen (HMF) and lower motility fresh semen (LMF), according to total motility (TM) and progressive motility (PM) values of fresh semen. Then the ejaculates was cryopreserved and assigned to higher motility thawed group (HMT) or lower motility thawed group (LMT) according to TM and PM at 0 h post-thawing. Multivariate analyses were performed to identify the association between the functional characteristics of fresh and thawed semen and the SP parameters, in terms of the oxidative status and the metabolomic composition. According to our results, the advanced oxidative protein products (AOPP) and thiol concentrations in SP are significantly related to some physiological characteristics of the thawed sperm, such as higher viability, TM, PM and LIN and lower mitochondrial and cytoplasmic superoxide production in viable thawed cells. In contrast, a higher amount of C in the SP was negatively related to TM and PM of thawed semen and was associated with higher mitochondrial and cytoplasmic superoxide production.In addition, partial least squares-discriminant analysis (PLS-DA) performed on the 1H NMR spectra indicated a discrete separation between HMF and LMF groups, and good discrimination between HMT and LMT groups. Higher levels of formic acid, lactate, glycerol and phosphocholine, were found in the SP of the HMF group than in the LMF group. On the other hand, alanine, phenylalanine, and tyrosine were higher in the SP of the LMF group than in the HMF group. GABA, glutamate, histidine and glycerol were found in higher concentrations in the HMT group than in the LMT group, while fructose decreased in the HMT group. Our results showed that the oxidative and metabolomic status of SP is related to the physiological properties of semen and its freezability and open new fields in research of SP biomarkers of bull semen preservation and fertility.

In recent years, concern has been increasing over the impact of environmental nanoplastics (NPs) contamination on both human and animal health, particularly regarding potential effects on reproductive systems. Nevertheless, current knowledge about the hazards posed by nanoplastics to mammalian gametes remains limited. In this study we evaluated the impact of increasing concentrations of polystyrene nanoplastics (PS-NPs)(5, 50, 100 and 200 μg/mL) on female gamete, using an in vitro model of pig oocyte maturation (IVM). Nuclear maturation, cytoplasmic maturation and developmental competence of oocytes, intracellular oocyte levels of glutathione (GSH) and reactive oxygen species (ROS), as well as steroidogenic activity of cumulus cells (CCs) were evaluated. Exposure to PS-NPs during IVM did not affect CCs steroidogenesis, oocyte nuclear maturation and oocyte cytoplasmic maturation in term of both fertilization parameters after IVF and blastocyst rate after parthenogenic activation. Nevertheless, PS-NPs significantly increased oocyte ROS levels at all the concentrations tested and compromised oocyte developmental competence, as indicated by reduced blastomere number per blastocyst. Our results confirm that PS-NPs may interfere with oocyte maturation and highlights the need to assess NPs exposure as an emerging environmental factor with potential implications for both animal and human fertility.

Semen preservation at 17 °C plays a pivotal role in the porcine breeding industry, though it presents challenges; not all ejaculates retain their quality during storage. Colloidal centrifugation has been developed to improve it since this method eliminates seminal plasma and microorganisms while simultaneously allowing the selection of spermatozoa based on gradient density centrifugation. This study aimed to evaluate whether two different colloid densities (1.026 g/ml - 20 %Porcicoll® and 1.104 g/ml - 80 % Porcicoll®) improve sperm bioenergetics, assessed using Agilent seahorse, along with key semen quality parameters such as viability, mitochondrial activity, oxidative stress and motility analyzed through flow cytometry and the CASA system over time. Fifteen ejaculates were divided into three groups: Control (CTR), 20 % Porcicoll® (P20), and 80 % Porcicoll® (P80). Sperm parameters were analyzed at days 0, 3, and 7 of storage. Results revealed a metabolic shift from mitochondrial oxidative phosphorylation to glycolysis during storage, with a 15 % decrease in ATP production by day 3. P80-treated sperm showed higher ATP production on day 0 compared to P20. Sperm quality parameters such as viability and mitochondrial activity decreased after colloidal centrifugation, possibly because of early capacitation; we also hypothesize that SLC could increase sensitivity to the high glucose levels in the medium. Although Porcicoll® effectively selected metabolically active sperm, the lack of seminal plasma and limitations in media composition negatively affected long-term sperm quality. Further research is necessary to optimize media formulations and assess fertility outcomes of selected sperm for enhanced sperm preservation techniques.

cAMP has been reported to be an essential driver of sperm capacitation. In bovine sperm cAMP efflux through multidrug resistance-associated protein 4 (MRP4) has been suggested to maintain intracellular cAMP homeostasis and generate extracellular signaling able to regulate capacitation. The aim of this work was to determine whether extracellular cAMP may influence in vitro pig sperm capacitation and acquisition of fertilizing ability and to evaluate the role of MRP4. In vitro sperm capacitation and gamete coincubation were performed in Brackett and Oliphant's medium (BO) in presence of caffeine (Ctr+) or in BO without caffeine (Ctr-) supplemented with 0, 8, 9, 10 mM cAMP. Despite the percentage of capacitated sperm, assayed by immunolocalization of tyrosine-phosphorylated proteins, was significantly lower in Ctr- compared to Ctr+, it increased supplementing 10 mM cAMP to Ctr- reaching values similar to Ctr+. The absence of caffeine during gamete coincubation reduced the fertilization rate compared to Ctr+, while 10 mM cAMP supplementation to Ctr- increased the fertilization rate reaching values similar to Ctr + . The presence of MRP4 in pig spermatozoa was detected for the first time by western blot and immunohistochemistry assays. To evaluate MRP4 role on pig sperm capacitation, in vitro capacitation and gamete coincubation were performed in Ctr + in presence of MK571, a MRP4 selective inhibitor. MK571 reduced the percentage of capacitated cells and the fertilization rate, while cAMP addition fully reversed MRP4 blockade consequences. Present findings suggest that, under our in vitro conditions, extracellular cAMP and MRP4 activity influence pig sperm capacitating events.

Porcine seminal plasma (SP) is loaded with a heterogeneous population of extracellular vesicles (sEVs) that modulate several reproductive-related processes. This study investigated the effect of two sEV subsets, small (S-sEVs) and large (L-sEVs), on porcine in vitro fertilization (IVF). The sEVs were isolated from nine SP pools (five ejaculates/pool) using a size-exclusion chromatography-based procedure and characterized for quantity (total protein), morphology (cryogenic electron microscopy), size distribution (dynamic light scattering), purity and EV-protein markers (flow cytometry; albumin, CD81, HSP90β). The characterization confirmed the existence of two subsets of high purity (low albumin content) sEVs that differed in size (S- and L-sEVs). In vitro fertilization was performed with in vitro matured oocytes and frozen-thawed spermatozoa and the IVF medium was supplemented during gamete coincubation (1 h at 38.5 °C, 5 % CO2 in a humidified atmosphere) with three different concentrations of each sEV subset: 0 (control, without sEVs), 0.1, and 0.2 mg/mL. The first experiment showed that sEVs, regardless of subset and concentration, decreased penetration rates and total IVF efficiency (P < 0.0001). In a subsequent experiment, it was shown that sEVs, regardless of subset and concentration, impaired the ability of spermatozoa to bind to the zona pellucida of oocytes (P < 0.0001). The following experiment showed that sEVs, regardless of the subset, bound to frozen-thawed sperm but not to in vitro matured oocytes, indicating that sEVs would affect sperm functionality but not oocyte functionality. The lack of effect on oocytes was confirmed by incubating sEVs with oocytes prior to IVF, achieving sperm-zona pellucida binding results similar to those of control. In the last experiment, conducted under IVF conditions, sperm functionality was analyzed in terms of tyrosine phosphorylation, acrosome integrity and metabolism. The sEVs, regardless of the subset, did not affect sperm tyrosine phosphorylation or acrosome integrity, but did influence sperm metabolism by decreasing sperm ATP production under capacitating conditions. In conclusion, this study demonstrated that the presence of sEVs on IVF medium impairs IVF outcomes, most likely by altering sperm metabolism.

Sperm metabolism consists of a sophisticated network of biochemical reactions and varies between species, resulting in different metabolic strategies for ATP production to maintain sperm functionality. ATP can be produced through glycolysis or in the mitochondria by oxidative phosphorylation (OXPHOS). Since OXPHOS is the predominant metabolic pathway in horses spermatozoa, various assessments of mitochondrial activity are used to evaluate fertility, utilizing techniques such as fluorescent probes analysed via microscopy or flow cytometry, and polarographic electrode assays to measure current flow in response to an applied voltage. Though, these methods are limited by low throughput, as they assess mitochondrial activity at a single time point under a specific treatment condition. This study explores, for the first time, the application of the Agilent Seahorse XFp Technology to evaluate metabolism in stallion spermatozoa. This method enables real-time measurement of cellular metabolism across multiple samples or experimental conditions simultaneously. Ejaculates from eight different stallions were collected, and pools were prepared from three of them. Sperm viability and mitochondrial activity were evaluated by fluorescence microscopy, sperm motility by a computer-assisted sperm analysis system, and sperm metabolism was analysed via the Seahorse XFp analyser. Results confirmed a preference for OXPHOS over glycolysis in ATP production in stallion sperm, with mitochondria contributing significantly to total ATP generation. The Seahorse XFp Technology proved effective in evaluating equine sperm bioenergetics, offering insights into metabolic pathways critical for sperm function. In conclusion, this technology grants a new method for high-throughput analysis of sperm metabolism and quality, which could be applied to future reproductive studies in male equine fertility.

Secretome is composed by proteins and microvesicles secreted by the granulosa cells that line the follicular wall. These bioactive compounds promote follicular growth and oocyte maturation, influencing oocyte metabolism. Hence, we hypothesized that addition of secretome from preovulatory follicular fluid (FF) to maturation medium may influence the meiotic competence and metabolism of cumulus-oocyte-complexes (COCs) obtained post mortem. FF was retrieved from preovulatory follicles (2 mares) after 32h of hCG administration. Three ml of FF from both mares were pooled, diluted 1:1 in PBS and centrifuged (4000g, 1h at 4°C) using a 10K Amicon® Ultra-15 Centrifugal Filter Unit and protein concentration was measured. A total of 186 COCs were retrieved from post mortem ovaries and were subjected to in vitro maturation (IVM) in TCM-199 medium, 10% of FBS and 5 mU/ml of FSH (Control; 59 oocytes) or with 20 µg/ml of secretome (Secretome20; 66 oocytes) or with 40 µg/ml of secretome (Secretome40; 61 oocytes) for 28 h in 5% CO2/95% air at 38.2°C. Oocytes were denuded, fixed in 4% formaldehyde and stained with Hoechst 33342 to assess chromatin conformation by fluorescence microscopy. Also, selected metabolites of the maturation medium prior to andafter IVM were assessed by magnetic proton nuclear resonance spectroscopy. After IVM, a trend towards glucose consumption and pyruvic acid production was observed compared to their controls prior IVM; a significant increase in lactic acid production in all treatments was observed (Table 1; p < 0.05). Our results show a tendency for quicker meiosis resumption in COCs incubated with Secretome40 (Table 2). In conclusion, secretome obtained from preovulatory follicular fluid added during IVM does not change COCs' energy metabolism nor maturation rate of equine cumulus-oocyte complexes in our in vitro culture system. Funding: MCCIN/AEI (PID2020-112723RB-I00; RYC-2017-21545; RYC2020-028915-I), Junta de Extremadura-FEDER (IB20005).

Seminal plasma contains many morphologically heterogeneous extracellular vesicles (sEVs). These are sequentially released by cells of the testis, epididymis, and accessory sex glands and involved in male and female reproductive processes. This study aimed to define in depth sEV subsets isolated by ultrafiltration and size exclusion chromatography, decode their proteomic profiles using liquid chromatography-tandem mass spectrometry, and quantify identified proteins using sequential window acquisition of all theoretical mass spectra. The sEV subsets were defined as large (L-EVs) or small (S-EVs) by their protein concentration, morphology, size distribution, and EV-specific protein markers and purity. Liquid chromatography-tandem mass spectrometry identified a total of 1034 proteins, 737 of them quantified by SWATH in S-EVs, L-EVs, and non-EVs-enriched samples (18-20 size exclusion chromatography-eluted fractions). The differential expression analysis revealed 197 differentially abundant proteins between both EV subsets, S-EVs and L-EVs, and 37 and 199 between S-EVs and L-EVs versus non-EVs-enriched samples, respectively. The gene ontology enrichment analysis of differentially abundant proteins suggested, based on the type of protein detected, that S-EVs could be mainly released through an apocrine blebbing pathway and be involved in modulating the immune environment of the female reproductive tract as well as during sperm-oocyte interaction. In contrast, L-EVs could be released by fusion of multivesicular bodies with the plasma membrane becoming involved in sperm physiological processes, such as capacitation and avoidance of oxidative stress. In conclusion, this study provides a procedure capable of isolating subsets of EVs from pig seminal plasma with a high degree of purity and shows differences in the proteomic profile between EV subsets, indicating different sources and biological functions for the sEVs.

AbstractThis study evaluated the bioenergetic map of mitochondria metabolism in cryopreserved bovine sperm. The detected oligomycin‐sensitive basal respiration supported ATP production; frozen–thawed spermatozoa were found to have a coupling efficiency higher than 0.80. Cell respiration, however, was not stimulated by the protonophoric action of FCCP, as its titration with 1, 2, 4 and 6 μM did not stimulate the uncoupling activity on oxidative phosphorylation as highlighted by unresponsive oxygen consumption. The unusual effect on the stimulation of maximal respiration was not related to fibronectin‐ or PDL‐coated plates used for cellular metabolism analysis. Conversely, irradiation of frozen–thawed bovine sperm with the red light improved mitochondrial parameters. In effect, the maximal respiration of red‐light‐stimulated sperm in PDL‐coated plates was higher than the non‐irradiated. In spite of this, red‐light irradiation had no impact on membrane integrity and mitochondrial activity evaluated by epifluorescence microscopy.

Cellular metabolism is an important feature of spermatozoa that deserves more insights to be fully understood, in particular in porcine semen physiology. The present study aims to characterize the balance between glycolytic and oxidative metabolism in boar sperm cells. Agilent Seahorse technology was used to assess both oxygen consumption rate (OCR), as an oxidative metabolism index, and extracellular acidification rate (ECAR), as a glycolytic index. Different metabolic parameters were studied on freshly ejaculated sperm cells (identified as day zero sample, d0) and after one day of storage at 17 degrees C in Androhep extender (d1). Mitochondrial ATP production rate (MitoATP) was higher than the glycolytic ATP production rate (glycoATP) at both d0 and d1 while at d1 the amount of ATP production decreased, in particular, due to OXPHOS reduction. Conversely, glycoATP was not significantly different between d0 and d1. Interestingly, OCR profile showed no different bioenergetic parameters (i.e. ATP turnover, basal or maximal respiration, and spare respiration) between d0 and d1, thus indicating that sperm cell metabolism was reversibly decreased by preservation conditions. Other metabolic parameters showed the same trend, irrespective of the storage time: under stressed conditions (oligomycin plus FCCP), spermatozoa showed an increase in mitochondrial respiration while the metabolic potential of glycolysis did not undergo variations when compared to baseline metabolism. The rate of oxidation of fuel substrates - glucose, fatty acids, and glutamine - showed that sperm reliance on glucose oxidation to maintain baseline respiration was higher than fatty acids or glutamine. Interestingly spermatozoa demonstrated to have a low "capacity" parameter, which indicates that they cannot use only a single fuel substrate to produce energy. This feature of sperm metabolism to be unable to increase oxidation of a particular fuel to compensate for inhibition of alternative fuel pathway(s) was demonstrated by the negative value of "flexibility". Our results showed that ATP production in boar sperm cells relied on mitochondrial oxidative metabolism in freshly ejaculated cells, while, under liquid storage conditions, their oxidative metabolism decreased while the glycolysis remained constant. These results open new fields of research in the preservation techniques of boar sperm cells.

After breeding or artificial insemination, especially with frozen/thawed semen, mares often develop a persistent uterine inflammation, which is diagnosed by intra-uterine fluid accumulation. Here, we explored whether intra-uterine fluid accumulation affects corpus luteum function and tested the hypothesis that intra-uterine fluid accumulation after artificial insemination alters blood flow in the corpus luteum and plasma progesterone concentrations. A total of 40 Standardbred mares were artificially inseminated with frozen-thawed semen 30 to 36 h after induction of ovulation, and cases with or without intra-uterine fluid accumulation were detected by ultrasound 12 h after insemination. Luteal blood flow was measured by Power Doppler ultrasonography 3 and 6 days after ovulation, progesterone concentration was measured in peripheral plasma by ELISA 6 days after ovulation, and pregnancy was diagnosed by ultrasonography 14 days after ovulation. Luteal blood flow increased between 3 and 6 days after ovulation, but blood flow did not differ significantly between cases with (n = 28) and without (n = 25) intra-uterine fluid accumulation after insemination. Surprisingly, progesterone concentrations were higher in cases of intra-uterine fluid accumulation than cases without (9.3 ± 1.1 vs. 6.6 ± 0.5 ng/mL, p = 0.048). Pregnancy was less likely in cases with intra-uterine fluid accumulation than in cases without (10/28 vs. 17/25, p = 0.019), and there was a negative correlation between the severity of intra-uterine fluid accumulation and per cycle pregnancy rate. These data suggest that although intra-uterine fluid accumulation increases the secretion of progesterone, pregnancy is more dependent on uterine health than ovarian function.