Clinical application of hysteroscopic hydrotubation for unexplained infertility in the mare.

BACKGROUND: Therapeutic techniques for oviductal obstruction in the mare are limited. Nonsurgical and retrograde flushing may be an attractive alternative to current treatment methods for oviductal blockage. OBJECTIVES: To evaluate hysteroscopic selective hydrotubation as a treatment option for presumptive equine oviductal blockage. STUDY DESIGN: Retrospective case series. METHODS: A quantity of 10 mL of saline was flushed through the oviducts in 28 standing sedated mares, which had reproductive histories of unexplained subfertility, by inserting a catheter into the uterotubal junction under endoscopic guidance. All mares in the study had been mated through several cycles (2-20 oestrous cycles) by known fertile stallions prior to treatment, with no evidence of conception. The average number of cycles for each mare prior to treatment was 6.5 ± 4.5. RESULTS: Saline was successfully infused into a total of 50 oviducts. Of 28 mares, 26 conceived after the treatment. The average number of cycles for each mare to become pregnant after treatment was 1.8 ± 0.8. MAIN LIMITATIONS: Diagnosis of blocked oviducts was presumptive, and pretreatment infertility was used as the control. CONCLUSIONS: This study revealed that hysteroscopic hydrotubation using saline improved pregnancy rates in mares in which oviductal blockage was suspected as a cause of unexplained subfertility.

Hysteroscopic hydrotubation of the equine oviduct.

REASON FOR PERFORMING STUDY: Diagnostic techniques for oviductal obstruction in the mare are limited and development of a more reliable and direct method to assess oviductal patency is needed. OBJECTIVE: To evaluate the feasibility of hysteroscopic selective hydrotubation of the equine oviduct via videoendoscopy in standing mares. METHODS: Using a catheter inserted under endoscopic guidance into the uterotubal junctions of 10 mares, 5 ml of indigo carmine solution (4 mg/ml) was flushed into the oviduct. After introduction of the dye, peritoneal fluid was obtained via abdominocentesis. A colpotomy was also performed to allow introduction of a videoendoscope into the abdominal cavity to assess the presence of dye visually at the ovarian end of the oviduct. RESULTS AND CONCLUSIONS: In 15 of 20 (75.0%) attempts, the catheter was successfully inserted into the uterotubal junction, and dye was observed at the ampulla, fimbria, overlying the ovary or surrounding tissue. In 2 mares, the videoendoscope could not be manipulated to identify the uterotubal junction. Only one of 2 oviducts was flushed in an additional mare because insufflation of the uterus could not be maintained. The colour of the dye was evident macroscopically and spectrophotometrically in 4 of 8 mares from which peritoneal fluid was successfully collected. POTENTIAL RELEVANCE: The equine oviduct can be evaluated by hysteroscopic selective hydrotubation.

Laparoscopic evaluation of oviductal patency in the standing mare.

Intraluminal masses in the oviduct might cause infertility and/or subfertility in mares by preventing transport of ova, sperm, or both, to the site of fertilization or the embryo into the uterus. Currently, there is no clinical test for oviductal patency in mares. The objective was to determine if the passage of microspheres from the oviduct to the uterus was associated with the presence or absence of intraluminal masses. In this trial, a standing laparoscopic technique was used to cannulate the oviducts and instill 15-µm fluorescent beads in 16 light-breed mares. At 48 hours after surgery, uterine lavage was performed to collect and quantify the number of beads transported to the uterus. Mares were immediately euthanized, and their reproductive tracts recovered. The presence of intraluminal masses was determined from postmortem evaluation and compared with the number beads recovered in the uterine lavage fluid. A test was considered positive for intraluminal masses if no beads were transported to the uterus. The sensitivity and specificity of the test were 71.4% and 85.7%, respectively.

Use of contrast sonography to test for tubal patency in dairy cattle.

Hysterosalpingo-contrast sonography is an accurate first-line method used to test for tubal patency in human gynecology. Tubal pathology occurs in dairy cattle and is a reason for infertility, but easy and accurate methods to test for tubal patency are not available in the living cow. In this study it was thus investigated if contrast sonography (CS) using Echovist-200 as the echo-contrast medium is a feasible procedure to test for tubal patency in dairy cattle. In eight repeat breeder Holstein Frisian cows, all of them being in behavioral estrus, Echovist-200 was given into the uterus and its exit into the abdominal cavity then imaged by transrectal conventional B-mode ultrasound, and used as indicator for tubal patency. Animals were slaughtered one day later and the genital tracts subjected to gross morphology and histology in order to confirm the results of CS. In two cows, CS was prematurely terminated after examination of one oviduct because of rectal bleeding, while CS completely failed in another cow because of poor image quality. In five cows, both oviducts could be examined by CS, respectively. A total of five oviducts were found patent by CS and confirmed by post mortem examination. Two out of five oviducts diagnosed as occluded by CS were morphologically intact and thus misdiagnosed. Of the three non-patent oviducts, two were occluded because of a hydrosalpings, respectively, while the third was inflamed. In conclusion, CS has been shown a feasible procedure to test for tubal patency in dairy cattle. Further studies with more animals are however recommended to warrant this result.

Assessment of oviduct potency in the cow.

A test of oviduct patency was developed, based on instillation of dye to the uterine horn through a two-way catheter. In 23 cows, two cases of bilateral and five cases of unilateral blockage were detected. Of 69 cow genital tracts collected from an abattoir, nine of 138 oviducts (7 per cent) did not permit the passage of dye. Fourteen of the remaining oviducts were found to blocked using a suspension of 80 micrometer pollen grains. This suggested that some animals showing patency to the dye test in vivo may in fact have abnormalities of the oviduct sufficient to prevent the passage of the ovum. In five cows, superovulation and embryo recovery were carried out as an investigation of oviduct patency and function. Although in one of the five cows, subsequently found to have a blocked oviduct, no embryos were recovered, ambiguous results were obtained in the other animals. The unpredictable response to superovulation may limit the application of this latter technique in investigation of oviduct patency and function.

The use of the starch grain and phenolsulphonphthalein tests to investigate infertile cows.

The starch grain and phenolsulphonphthalein (PSP) tests were used to investigate the patency of the fallopian tubes in five "repeat breeder" cows. Evidence of tubal lesions was determined in three cows on rectal palpation. Using the starch grain test, bilateral occlusion was determined in three animals, left sided occlusion was determined in one and right sided occlusion in another. Using the PSP test there was evidence of bilateral occlusion in two of the four coes which were tested. In four cows the genital organs were examined visually and by palpation at laparotomy and in two cows tubal occlusion was confirmed when they were flushed with saline, and patency restored. In one animal both ovaries were almost completely encapsulated, while in the fourth adhesions involving the fimbriae occluded the ostia. There were broken down and this cow was the only one which subsequently conceived.