Roussev RG, Acacio B, Ng SC, Coulam CB, Am J Reprod Immunol - 2008 Sep;60(3):258-63.

In vitro investigations have revealed the ability of intralipids to suppress natural killer (NK) cytotoxicity. Evidence from both animal and human studies suggests that intralipid administered intravenously may enhance implantation and maintenance of pregnancy when the patient has an abnormal NK cell level or function.

The aim of this study was to establish the duration and efficacy of Intralipids suppressive effect on NK cell functional activity.

Fifty women with abnormal NK-testing received intralipid infusions. 39 (78%) showed NK suppression within the normal range the first week after infusion, 11 (22%), showed suppression, but still above the normal threshold. They received second infusion 2-3 weeks later. In 10, the NK activity was normalized the following week. Four patients had three intralipid infusions in 2-week periods in between and after the third infusion, and all showed NKa normal activity. In 47 patients the suppressive effect of the Intralipid after the normalization of NK lasted between 6 and 9 weeks, in two patients this benefit lasted 5 weeks, and in one patient the effect was 4 weeks.

Intralipid is effective in suppressing in vivo abnormal NK-cell functional activity. The results suggest that Intralipid can be used successfully as a therapeutic option to modulate abnormal NK activity in women with reproductive failure.