Very high intakes of the retinol or animal form of vitamin A (more than 10 times the recommended daily amount) have been associated with birth deformities. The plant form of vitamin A, beta-carotene, found in many vegetables and fruit, is perfectly safe.

Liver and liver products such as liver pâté contain large amounts of the retinol form of vitamin A and the Department of Health has advised they should not be eaten during pregnancy.

Cod liver oil supplements and any supplements containing vitamin A in the form of retinol should be checked so that they do not contain too much. The recommended upper limit of retinol from supplements is 3,000 micrograms per day.