Short luteal phase experts - what can I do?! My LP is usually 8 or 9 days, I took vitamin B complex last cycle and it was 10 which I was very happy about as I know an extra day or two might make all the difference. However, I have continued with it this cycle and now a 7 day one! Any advice would be much appreciated. I am aged 40, and this was cycle 6 TTC no.2.