Can weight loss cause intracyclic spotting?

Good morning. I take 6 packs of Vixpo tablets. In 5 packs there was a brown middle-cyclical bleeding (4 days before taking placebo tablets) in 6 packs it occurred again in the 2nd week of the blister and lasts already two weeks. Recently I am on a diet and I lost 8kg. Could this affect these bleedings? I did not take any herbs or antibiotics that could weaken contraception. There was no vomiting or diarrhoea. Normal cytology done 2 msc ago. Unfortunately, but a visit to the doctor only in 2 weeks.