Intralipid supplementation in women with recurrent spontaneous abortion and elevated levels of natural killer cells

Abstract Objective To investigate the efficacy of intralipid supplementation in women with recurrent spontaneous abortion (RSA) and elevated natural killer cell activity undergoing in vitro fertilization/intracytoplasmic sperm injection. Methods Between February 10, 2013, and April 30, 2015, a double-blind randomized controlled study was conducted at a center in Egypt. Women with unexplained secondary infertility, RSA, and elevated levels of natural killer cells (> 12%) were enrolled and randomly assigned to receive intralipid (2 mL diluted at 20% in 250 mL saline) or saline (250 mL) infusion on the day of oocyte retrieval using random numbers and sealed envelopes. Patients and attending physicians were masked to group assignment. The infusions were repeated within 1 week of a positive pregnancy test and then every 2 weeks until the end of the first trimester. The primary outcome was chemical pregnancy 14 days after embryo transfer. Analyses were by intention-to-treat. Results Overall, 296 women were enrolled. Chemical pregnancy was recorded for 84 (58.3%) of 144 women in the intralipid group and 76 (50.0%) of 152 in the control group ( P  = 0.129). Conclusion Intralipid supplementation did not increase frequency of chemical pregnancy. However, findings related to ongoing pregnancy and live birth should be investigated further. ClinicalTrials.gov: NCT01788540