Is dark bleeding when using Vines a cause for concern?

It is probably spotting or mid-cycle bleeding - a side effect, especially often associated with taking contraceptive pills with a lower content of hormones, such as Vines. They occur especially at the beginning of the use of contraceptive pills, and sometimes also after a long time, e.g. as a result of illness or excessive stress. This is usually not a cause for concern. It also has no effect on the effectiveness of contraception. Below are the materials that may be of interest to you: https://www.gdziepolek.pl/artykuly/jak-prawidlowo-stosowac-antykoncepcje https://www.gdziepolek.pl/artykuly/jakie-leki-oslabiaja-skutecznosc-antykoncepcji https://www.gdziepolek.pl/blog/historia-antykoncepcji-metody-zapobiegania-ciazy-kiedys-i-dzis