Altered bleeding patterns

Troublesome bleeding is a common reason for discontinuing the progestogen-only pills (POPs) containing levonorgestrel or norethisterone. Frequent and irregular bleeding are common; amenorrhoea and prolonged bleeding are less common.

Data for rates of abnormal bleeding with POPs containing drospirenone are limited, but study withdrawal rates attributed to abnormal bleeding are low (around 3%); in one study, amenorrhoea was reported in 45% of users by cycle 9.

Some POP users experience no change in their menstrual cycle.

If bleeding is troublesome, switching POP formulations is an option or, if using a POP containing levonorgestrel or norethisterone, a double dose can be tried, though evidence is lacking.