If you have been postponing parenthood for some reason, it's a good idea to talk to an expert to be aware of all your options. Vitex (also called Chaste tree or Chaste berry) is a popular and effective herbal medicine. I prescribe it all the time. I also frequently de-prescribe Vitex when I can see it is doing more harm than good. Whether you’re trying to plan or prevent pregnancy, it can be helpful to know when you are ovulating. You are most fertile 12-24 hours after ovulation, which is when your body releases an egg cell that then moves into the fallopian tube. Unfortunately, low progesterone is really common. Though this is often not severe enough to affect fertility, there are many other things that can be affected, as seen in my post about why to work on your hormonal health even if you aren’t trying to get pregnant.