The luteal phase of the menstrual cycle is the phase after ovulation and before the start of the period. If you are charting your menstrual cycles then this will consist of the phase post ovulation, usually calculated from the first day on which your basal body temperatures is above the cover line until the day before your period.. I'm on my 4th month of ttc no 2 and have noticed my LP is 9 days. After doing a little googling, bad i know, I'm all worried about scary sounding lut. Anything below 10 days is known as a luteal phase defect so you're borderline I suppose! Have you considered a dose of b6! I had a 10 day luteal phase and now after taking b6 daily it's 12 days!. Thanks for posting about this op :) I'm having really short luteal phases lately it's odd. Last month my af was 5 days early and this month I have had spotting already at 6 days early!!!. Snap lol, just posted something similar about our daughter. She’s just had a bfp at 11 days post ovulation, last month her luteal phase was just 8 days, we’re keeping everything crossed it doesn’t come away.. 10 days is long enough to get pregnant, but only just. as you say, vit B6 can lengthen it and so can vitex (depending on the cause of it being shorter than average).