Some types of infertility may be caused by a slightly overactive immune system. When this occurs the immune system can attack egg, sperm, embryo and even a developing fetus. This can result in difficulty achieving pregnancy, maintaining the pregnancy, or repeated miscarriages.

Natural killer (NK) cells are regulated by the immune system. In women who have autoimmune issues, the NK cells can react abnormally to an implanting embryo, treating it as an invading cell and signalling for the body to attack it.

Intralipidshave been shown to lower the activity of the NK cells component of our immune system. Studies have found that intralipids can help to regulate the NK cells, allowing the embryo to implant on the uterine wall and grow normally. New research has suggested that women who have experienced recurrent miscarriages or multiple failed IUI or IVF cycles as a result of NK cell activation may benefit from the use of intralipids.