Need some opinions on vitex☺️

Hannah • Me & my SO are actively ttc baby #1 for over 3 years with PCOS and Hydrosalpinx 🤞🏻🙏🏻✨
So I just a bought vitex today. I've read a lot about it I decided to take it because my cycles are so long. I'm currently on my period so my question to any of you is when should I start taking it? I've read some say your whole cycle or only the first half or only the second half (after ovulation). If any of you can give me some feed back that would be amazing☺️