A rare and unusual case of advanced complete molar pregnancy in an Arabian mare: first report.

Overview

• The article reports the first documented case of an advanced complete molar pregnancy in an Arabian mare, characterized by the presence of fetal membranes without an embryo, resulting in delayed parturition and requiring surgical intervention.

Introduction to Molar Pregnancy

• Molar pregnancy is a rare condition, commonly reported in humans, involving abnormal growth of fetal membranes.
• It may occur with or without the presence of an embryo.
• This case illustrates molar pregnancy in a non-human species: a horse.

Case Presentation

• A 22-year-old Arabian mare was referred to the veterinary clinic due to delayed parturition, suggesting complications in the pregnancy.
• Ultrasound examination revealed suspended uterine membranes floating in fluid but no fetal organs or fetus were detected.

Clinical Approach and Findings

• The mare underwent a caesarean section to resolve the pregnancy.
• Upon surgery, the uterus contained a mixture of brown fluid and fragments of fetal membranes.
• Critically, no fetus or fetus remnants were found in the uterus, which is unusual for a pregnancy at this stage.

Histopathological Examination

• Microscopic analysis of the fetal membranes showed severe degenerative changes.
• The uterine lining (endometrium) had lost its normal layered structure.
• The distinct layers of stratum spongiosum and stratum compactum were no longer separable, indicating pathological change.

Treatment Outcome and Significance

• The uterus was thoroughly evacuated to remove abnormal contents as much as possible.
• Following surgery, the mare recovered fully and regained health.
• This is notable as the first reported case of a continued pregnancy without an embryo in a horse.
• The case suggests the occurrence of a rare and unusual type of molar pregnancy in equine species.

Implications

• This report contributes valuable information regarding equine reproductive disorders and possible parallels with human molar pregnancies.
• It highlights the need for further research into molar pregnancies in animals for better diagnosis and treatment.
• The unusual presentation challenges veterinary practitioners to consider molar pregnancy in differential diagnoses when faced with delayed parturition and unusual ultrasound findings in mares.