The 29-year-old took to her Instagram page on Monday (08Feb16) to tell fans her plans to promote season six have been axed due to her struggle with endometriosis, which causes inflammation outside of the uterus, pelvic pain, fatigue, nausea, and possible infertility.

"Hey Beloved Pals, I just wanted to let you know that, while I am so excited for Girls to return on Feb 21, I won't be out and about doing press for the new season," she began. "As many of you know I have endometriosis, a chronic condition that affects approximately 1 in 10 women's reproductive health. I am currently going through a rough patch with the illness and my body (along with my amazing doctors) let me know, in no uncertain terms, that it's time to rest."

Lena created the hit HBO series in 2012 and plays lead character Hannah, so going from such a fast-paced working environment to being housebound does not sit well with the star.

"That's a hard thing to do, but I'm trying, because all I want is to make season 6 of Girls the best one yet," she continued. "I'm lucky enough to have support and backup from (producers) Jenni (Jennifer Konner), Judd (Apatow) and the whole Girls gang. So many women with this disease literally don't have the option of time off and I won't take it for granted. Wishing you all health & happiness, in whatever form suits you. Back soon xxLena."

Lena first opened up about her battle with the condition in November (15) in her weekly newsletter, Lenny Letter.