The effect of prednisolone on endometrial uterine NK cell concentrations and pregnancy outcome in women with reproductive failure. A retrospective cohort study.

This retrospective study of prospectively collected data examines the effect of prednisolone therapy on raised uterine Natural Killer cell (uNK) concentrations and pregnancy outcomes in women with recurrent miscarriage (RM) and recurrent implantation failure (RIF) after IVF/ICSI treatment. 136 women diagnosed with RRF who had a timed midluteal endometrial biopsy taken for uNK cell analysis were included. Women with high uNK cell concentrations (n = 45) were treated with prednisolone (10 mg/day) for one month, after which a second biopsy was taken for repeat uNK cell analysis.

Measurement of uterine natural killer cell percentage in the periimplantation endometrium from fertile women and women with recurrent reproductive failure: establishment of a reference range.

Background: Uterine natural killer cells are the major leukocytes present in the periimplantation endometrium. Previous studies have found controversial differences in uterine natural killer cell percentage in women with recurrent reproductive failure compared with fertile controls.

Objective: We sought to compare the uterine natural killer cell percentage in women with recurrent reproductive failure and fertile controls.

Standardisation of uterine natural killer (uNK) cell measurements in the endometrium of women with recurrent reproductive failure.

Considerable work is being carried out on endometrial NK cells to determine whether they play a role in successful pregnancy outcome. In addition there is debate about whether measurements of uNK should be included in the clinical assessment for women with recurrent implantation failure or recurrent miscarriage. A hindrance to taking this forward is the fact that the density of uNK cells reported by different centres is very different.

The effect of a high progesterone concentration before oocyte retrieval on the peri-implantation endometrium.

In this single-centre, prospective cohort study, the effect of high progesterone level before oocyte retrieval on endometrial morphology and uterine natural killer cell (uKN) count in the peri-implantation period was investigated. A total of 106 women undergoing IVF treatment who did not proceed to fresh embryo transfer were included. Endometrial samples were obtained 7 days after HCG administration.

The prognostic value of uNK cell count and histological dating in the mid-luteal phase of women with reproductive failure.

Objective: Histological dating has been used for decades to evaluate the histological maturation of the endometrium. Uterine natural killer cells are thought to play a significant role in pregnancy. While several studies have shown an increased number of uNK cells in women with recurrent reproductive failure, its prognostic value of pregnancy outcome remains uncertain.

Do uterine natural killer cell numbers in peri-implantation endometrium predict hypertensive disorder in pregnancy in women with a history of reproductive failure?

The aim of this study was to investigate whether or not increased uterine natural killer (uNK) cell numbers in the peri-implantation endometrium are associated with an increased risk of hypertensive disorders in a subsequent pregnancy. This is a retrospective study including 80 women with a history of unexplained recurrent miscarriage or recurrent implantation failure. Precisely timed endometrial biopsies were obtained from women 7-9 days after the luteinising hormone surge.

The clinical characteristics of women with recurrent implantation failure.

Recurrent implantation failure (RIF) refers to failure to conceive after three or more in vitro fertilisation (IVF) or embryo transfer cycles. Implantation failure may be due to embryo or uterine factors. There are many controversies surrounding the investigation and management of this condition.

The observer and cycle-to-cycle variability in the measurement of uterine natural killer cells by immunohistochemistry.

The aim of the study was to investigate the various potential sources of variability of counting endometrial uNK cells by immunohistochemistry. Precisely timed endometrial biopsy samples were obtained from women suffering from recurrent miscarriage or recurrent implantation failure (RIF) after IVF on days LH+7-LH+9 of the cycle. uNK cells in wax embedded sections were immunostained for CD56+ and expressed as a percentage of total stromal cells.

The correlation of autoantibodies and uNK cells in women with reproductive failure.

There is conflicting evidence on the role of autoimmune disorders in reproductive failure, including recurrent miscarriage (RM) and recurrent implantation failure (RIF), after in vitro fertilisation (IVF). Several commonly studied autoimmune markers in women with reproductive failure include antiphospholipid antibodies (APAs), thyroid peroxidase antibodies (TPA) and uterine natural killer (uNK) cells. However, there have not been any studies that have examined the correlation of these markers in women with reproductive failure.

Expression of leukaemia inhibitory factor and interleukin 15 in endometrium of women with recurrent implantation failure after IVF; correlation with the number of endometrial natural killer cells.

Background: Several studies have suggested that endometrial interleukin 15 (IL-15) and the leukaemia inhibitory factor (LIF) may be important in embryo implantation. IL-15 is postulated to play a role in the control of uterine natural killer (uNK) cell proliferation and function, and uNK cells are also known to play a role in implantation. The aims of this study was to (1) compare endometrial levels of IL-15 and the LIF in women with recurrent implantation failure (RIF) after IVF with those in fertile women (controls) and (2) examine the relation of IL-15 and LIF levels to the uNK cell number.

Measurements of CD56+ cells in peripheral blood and endometrium by flow cytometry and immunohistochemical staining in situ.

Background: CD56+ cells in peripheral blood or the endometrium may be increased in women with reproductive failure. However, the relationship between numbers of peripheral blood CD56+ and endometrial CD56+ cells is uncertain. The aim of this study was (i) to compare the numbers of CD56+ cells in peripheral blood and endometrium in samples taken simultaneously and (ii) to compare measurements by flow cytometry and immunohistochemistry of CD56+ cells in the same endometrial biopsy.

Uterine natural killer cells in peri-implantation endometrium from women with repeated implantation failure after IVF.

Several studies have suggested that endometrial uNK (CD56+) cells may play a role in implantation. The aim of this study was to investigate the number of CD56+, CD16+ and CD69+ cells in the unstimulated endometrium of women with recurrent implantation failure after IVF. The percentage of stromal cells positive for CD56, CD16 and CD69 was identified by immunocytochemistry in endometrial biopsies from 15 normal control women and 40 women with recurrent implantation failure.