A 7-year-old female entire Birman was referred for further investigation of acute-onset haemorrhagic vulvar discharge. A survey lateral abdominal radiograph was performed at the referring veterinary clinic, and a markedly enlarged uterus was noted. Cursory abdominal ultrasound identified at least three fetuses, with heart rates for each estimated to be in the region of 240 beats per min (bpm). The queen had a history of two prior litters, with no associated complications. On initial presentation at our veterinary teaching hospital, the cat was bright and alert, with subjectively pale mucous membranes. Apart from the vulvar discharge described above, with associated matting of the coat over the perineum, no further significant findings were appreciated on the rest of the physical examination. Vital parameters were within normal limits. Abdominal palpation revealed at least two palpable fetuses. The body condition score was 3/9. No known toxin exposure (acetaminophen, onions) was reported. Haematology revealed a moderate, normocytic, normochromic, non-/pre-regenerative anaemia, along with a moderate mature neutrophilia (; day 1). Saline test for agglutination was positive. No haemotropic mycoplasmas were identified. Serum biochemistry demonstrated severe hyperbilirubinaemia (26 µmol/l; reference interval [RI] 0–5 µmol/l), moderately increased aspartate aminotransferase (334 IU/l; RI 0–66 IU/l), moderately increased alanine aminotransferase (311 IU/l; RI 0–100 IU/l), mild azotaemia (blood urea nitrogen 16.0 mmol/l; RI 5.7–12.9 mmol/l), mildly increased symmetric dimethylarginine (16 µg/dl; RI 0–14 µg/dl), mild hypokalaemia (3.2 mmol/l; RI 3.5–5.0 mmol/l) and moderate hypoproteinaemia (55 g/l; RI 63–83 g/l), composed of a moderate hypoalbuminaemia (19 g/l; RI 26–40 g/l) and normal globulin concentration (36 g/l; RI 27–49 g/l). The cat was negative on testing for both FeLV and feline immunodeficiency virus. Serology for toxoplasmosis revealed a titre of 1:512, and the cat was feline blood group B. Focal reproductive tract ultrasonography was performed to assess fetal viability, and better estimate stage of gestation, should any further intervention be required. A large uterus, containing at least three subjectively well-developed fetuses was identified. Two of the fetuses failed to exhibit independent motion or cardiac activity, and the third had a heart rate of 218 bpm, indicating fetal stress. Fetal development was advanced, with visibility of the cerebral choroid plexi, and individual heart chambers consistent with at least 50 days’ gestation (). Morphology of fetal organs was well defined and similar in all fetuses, indicating that the demise of two fetuses had occurred within the preceding 12 h. The zonary placenta were varied in appearance, and at least one was subjectively thickened, with an irregular inner margin. This zonary placenta had several small areas of heterogeneously increased echogenicity, where the normal hyperechoic inner, hypoechoic middle and hyperechoic outer layers were not visible. Another region of zonary placenta was diffusely hyperechoic (). In addition, the uterus contained a moderate amount of strongly echogenic fluid contained in multiple pockets. A moderate amount of anechoic free peritoneal fluid was also present, along with subtly hyperechoic fat adjacent to the uterus. The owner expressed no desire to continue breeding with the queen in the future, and with at least two of the fetuses no longer viable, and the third deemed unlikely to survive to term and/or delivery, OVH was advised. Exploratory laparotomy revealed a moderate amount of straw-coloured fluid in the caudal abdomen. Fluid analysis revealed mild increases in protein (31 g/l; RI 0–28 g/l) and nucleated cell count (2.6 ×109/l; RI 0–1.5 × 109/l), with the latter composed of a small number of reactive mesothelial cells and occasional non-degenerate neutrophils and red blood cells. The gravid uterus appeared grossly congested and contained four fetuses. Recovery from anaesthesia was uneventful, and the cat was maintained on buprenorphine (0.025 mg/kg SC q8–12h) for pain management. Repeat haematology 3 days later revealed mild improvement in the degree of anaemia, along with evidence of regeneration (; day 4). The mature neutrophilia had since resolved; however, the cat was still positive on saline test for agglutination (; day 4). With gradual improvement in terms of both the degree of anaemia and regenerative response following surgery, no further treatment, more specifically immunosuppressive therapy, was instituted and the cat was discharged. Histology later revealed mild, multifocal suppurative placentitis, with Gram staining failing to demonstrate evidence of bacteria within the inflamed areas of placenta. Unfortunately, routine bacterial culture could not be performed to definitively rule out underlying bacterial infection. The IMHA described was deemed most likely to be associated with pregnancy, as is well documented in people. A revisit at the referring veterinary clinic 1 week later demonstrated further improvement, with a low normal haematocrit and moderate reticulocytosis; however, a weak positive was still noted on saline test for agglutination (; day 11). Further follow-up 1.5 months after OVH revealed complete resolution of the previously reported anaemia (; day 44). Repeat serology for toxoplasmosis revealed a titre of 1:1024.