For women receiving oestrogen replacement therapy there is an increased risk of endometrial cancer, which can be countered by progesterone administration.
In women with an intact uterus it is recommended to add a progestogen for at least 12 days of each month, in accordance with the manufacturers’ recommendations.1
References:
1. Oestrogel Summary of Product Characteristics. Available from https://www.medicines.org.uk/emc/product/353/smpc Last accessed: October 2021.
2. Panay N, Post Reprod Health 2014;20(2):69-72.
17. Utrogestan Summary of Product Characteristics. Available from https://www.medicines.org.uk/emc/product/352/smpc Last accessed: May 2021.
18. Fournier A, et al. Am J Epidemiol 2014;180(5):508-517.