How can I increase my lp?

[mrsclt]

Looking for advice on lenghtening my lp, last cycle it was either 7 or 9 days long. Not sure which, graph was a bit hard to interpret due to night waking, and getting up too early at times due to my lo. Either way, its too short... I've heard of something called Vitex being used but I dont know much about about what it is or how much to take or when to start... is it safe to take when breastfeeding? Is there anything else I can try to increase my lp? Any advice would be greatly appreciated.