Potential effect of inflammation on the failure risk of in vitro fertilization and embryo transfer among infertile women

Molecular Determinants of Uterine Receptivity: Comparison of Successful Implantation, Recurrent Miscarriage, and Recurrent Implantation Failure

Embryo implantation is one of the most remarkable phenomena in human reproduction and is not yet fully understood. Proper endometrial function as well as a dynamic interaction between the endometrium itself and the blastocyst-the so-called embryo-maternal dialog-are necessary for successful implantation. Several physiological and molecular processes are involved in the success of implantation. This review describes estrogen, progesterone and their receptors, as well as the role of the cytokines interleukin (IL)-6, IL-8, leukemia inhibitory factor (LIF), IL-11, IL-1, and the glycoprotein glycodelin in successful implantation, in cases of recurrent implantation failure (RIF) and in cases of recurrent pregnancy loss (RPL). Are there differences at the molecular level underlying RIF or RPL? Since implantation has already taken place in the case of RPL, it is conceivable that different molecular biological baseline situations underlie the respective problems.

The Relationships among Plasma Fetuin-B, Thyroid Autoimmunity, and Fertilization Rate In Vitro Fertilization and Embryo Transfer

OBJECTIVE

The objective of the study is to investigate the relationships between fetuin-B, thyroid autoimmunity (TAI), and pregnancy outcomes in women undergoing in vitro fertilization and embryo transfer (IVF-ET). Design, Patients, and Measurements. In this prospective study, 180 women who were preparing for pregnancy with IVF-ET were included. There were 120 women with TAI positive and 60 negative controls matched with age and BMI.

RESULTS

The 180 women had mean ± SD age of 31.4 ± 4.0 years, with a mean ± SD BMI of 21.0 ± 1.6 kg/m². There was a significant difference in the level of fetuin-B in women with TAI positive compared with TAI negative group (65.2 ± 18.5 vs. 76.4 ± 25.1, P=0.001). Fetuin-B had a negative relationship with thyroid antibodies even after adjusting for other variables (OR (95%CI) = 0.98 (0.96-0.99), P=0.002). Compared with women with TAI negative, those with TAI positive had a significantly higher risk of low fertilization (20.0% vs. 6.7%; P=0.035). And we found no difference in terms of pregnancy, abortion, implantation, and live birth rate between the two groups. Logistic regression analysis showed that both fetuin-B and TAI were the independent factors to lead the low fertilization of IVF-ET (OR (95%CI) = 0.96 (0.94-0.99) and 4.084 (1.39-15.30), P=0.004 and 0.019, respectively).

CONCLUSION

Fetuin-B was significantly associated with TAI and low fertilization rate in women undergoing IVF-ET. Decreased fetuin-B in women with TAI may be the underlying reason for the lower IVF-ET success rate.

Serum zinc concentration and risk of adverse outcomes to in vitro fertilization and embryo transfer: A prospective cohort study in northern China

Zinc (Zn) plays an important role in female reproductive health. Few studies have currently assessed the effects of female Zn level on the outcome of in vitro fertilization-embryo transfer (IVF-ET). This study investigated the association between serum Zn concentration and IVF-ET outcomes, and the potential effects of some lifestyles on this association. A prospective cohort study design was adopted, and 305 women undergoing IVF-ET were recruited from two cities, Beijing and Shandong, in northern China. Fasting blood specimens were obtained on the day prior to the first treatment cycle. A questionnaire was used to collect demographic characteristics and lifestyle information. Serum Zn concentration was measured using inductively coupled plasma-mass spectrometry. Female serum Zn levels in Beijing center were found to be significantly higher than those in Shandong center. Women who failed to achieve clinical pregnancy had significantly lower Zn concentrations among Shandong subjects, but not in Beijing or the total participants in both centers. For Beijing participants, no statistically significant associations were found between Zn concentrations and the failure risk of IVF-ET [adjusted relative risk (aRR) = 0.65, 95% confidence interval (CI): 0.37-1.15]. For Shandong participants, lower Zn concentrations (< 610.3 ng/mL) were associated with a 66% increased risk of IVF-ET failure (aRR = 1.66, 95% CI: 1.10-2.51). Also, significantly positive correlations were observed between Zn concentrations and the habitual consumption of two food types, including fresh vegetables and beans or bean products, but this was not the case in Beijing. It was concluded that the effect of serum Zn concentrations on IVF-ET outcome may vary by the geographic location. Lower Zn levels might be a risk factor for IVF-ET failure among Shandong women, which can be addressed by adjusting the food intakes. These findings have implications for human infertility treatment and public health problem addressing.