Background: Carbon monoxide is produced in abundance in the Niger Delta, a fact that was acknowledged in the World Bank study of the region in 1995 and the Environmental assessment of Ogoni land by UNEP in 2011. Objectives: To ascertain the extent of CO pollution in the Niger Delta, its impact on foeto-maternal health and to review the pathophysiology and the treatment of the poisoning. Methods: A mixed method study (observational-descriptive and systemic review). A literature review on the above objectives was carried out. The known foeto-maternal impact of CO exposure was extrapolated to the prevailing state of CO pollution in the Niger Delta. Questionnaires distributed to Doctors working in the tertiary Centres in the core Niger Delta focused on the prevalence, clinical presentations and foeto-maternal findings in patients who presented with CO poisoning. Results: There was no data on the prevalence and clinical presentations of CO pollution in the Niger Delta. The ambient and indoors air concentration of CO in the Delta range from 0 ppm to 191μg/m3 but in places within 60-200 metres from crude oil flow stations, the concentrations range from 100 to 5320 μg/m3. Maternal impact of CO pollution ranges from headaches at carboxyhaemoglobin (COHb) levels of 5-20% to maternal death at COHb levels of >66% while in the foetus, it causes birth defects, growth restriction, prematurity and sudden intrauterine and early neonatal death. Conclusion: The core Niger Delta is under perpetual siege of CO pollution and the ambient and indoors air concentration of it in the Delta range from 0 ppm to 191μg/m3.