Aggressive angiomyxoma is a rare, locally aggressive myxoid mesenchymal tumour that predominantly arises from the pelvis and perineum of young adult females. Occasional cases have been reported at unusual sites. Oestrogen and progesterone may play a role in the development of the tumour especially during pregnancy. A 25 year old Nigerian woman presented with severe abdominal pain shortly after a fresh still birth. Clinical and radiological evaluation revealed a massive intra-abdominal mass which was excised and pathologically diagnosed as aggressive angiomyxoma. The follow up period has been uneventful. This case demonstrates that aggressive angiomyxoma may present as a primary intra-abdominal mass and thus should be considered in the differential diagnosis of such lesions as this will greatly impact on its surgical management. Moreover, pregnancy appears to influence rapid tumour growth and may result in massive tumour sizes. Long term patient follow-up is routinely advocated for the early detection of tumour recurrence.