Soluble HLA-G promotes Th1-type cytokine production by cytokine-activated uterine and peripheral natural killer cells.

Soluble forms of HLA-G (sHLA-G) have been implicated in immune regulation. Fetal trophoblast cells are a prime source of HLA-G. Hence, an interaction between sHLA-G and uterine lymphocytes in the decidual tissues can easily be envisaged.

Two cycles with single embryo transfer versus one cycle with double embryo transfer: a randomized controlled trial.

Background: With the aim of reducing the number of multiple pregnancies after IVF we investigated the effectiveness of two cycles with single embryo transfer (SET) and one cycle with double embryo transfer (DET) after IVF and calculated the cost-effectiveness of both strategies.

Methods: A randomized controlled trial was performed in 107 women, aged <35 years, in their first IVF cycle, with at least one good quality embryo. They were randomized to the SET (n = 54) or DET (n = 53) group using a computer-generated random block number table, stratified for primary or secondary infertility.

Hormonal stimulation for IVF treatment positively affects the CD56bright/CD56dim NK cell ratio of the endometrium during the window of implantation.

The effects of hormone stimulation for IVF treatment on endometrial receptivity remain controversial. Since CD56(bright) natural killer (NK) cells in the endometrium positively contribute to implantation and decidualization whereas CD56(dim) NK cells are negatively associated with reproduction, shifts in the balance between those cells will affect receptivity. Therefore, we compared the leukocyte composition in the endometrium of IVF women (n=20) with non-pregnant women (n=18) in a natural cycle, as a parameter for endometrial quality.

Cost analysis of singleton versus twin pregnancies after in vitro fertilization.

Objective: To determine the difference in costs between singleton and twin pregnancies after IVF treatment from pregnancy to 6 weeks after delivery from a health care perspective.

Design: Retrospective cost analysis.

Setting: IVF department at the University Medical Center Nijmegen, The Netherlands.

Membrane-bound HLA-G activates proliferation and interferon-gamma production by uterine natural killer cells.

The expression of HLA-G by invading trophoblasts suggests a role for this molecule in embryo implantation. Putative targets for HLA-G are the uterine natural killer cells (uNK) that are abundantly present at the time of implantation. Since NK cells are potent producers of a variety of cytokines, interaction with HLA-G may result in the production of cytokines involved in trophoblast differentiation or tissue remodelling.