Aberrant immune responses may be related to infertility, implantation failure and recurrent pregnancy loss. The regulation of uterine and circulating peripheral blood natural killer (NK) cells has been associated with reproductive failure with NK cells reacting abnormally to an implanting embryo, treating it as an invading cell and signalling for the body to attack it.
The prognostic value of measuring peripheral or uterine NK cells however remains uncertain. The value/role of NK cell assessment as a predictive test for screening women who may benefit from immunotherapy has not been proven with most studies being insufficiently large enough to make a proper assessment.
Intralipid has been shown to suppress Natural Killer Cell toxicity as evidenced by both animal and human studies. Studies have found that intralipids can help to regulate NK cells, allowing the embryo to implant on the uterine wall and grow normally. 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.