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Updated: May 31, 2026
12:33
Corticospinal Excitability Modulation During Action Observation
Published on: December 31, 2013
The power of observation.
1Departments of Medicine, Molecular Medicine & Pathology, & Ob-Gyn., McMaster University, 1200 Main Street West, Hamilton, ON, Canada. clarkd@mcmaster.ca
Summary
Intravenous immunoglobulin (IVIG) plus anti-TNF-α therapy improved delivery and live birth rates in recurrent in vitro fertilization (IVF) failure patients by correcting elevated Th1/Th2 cytokine ratios. Optimal timing suggests improved follicle development.
Area of Science:
- Reproductive Endocrinology
- Immunology
- Evidence-Based Medicine
Background:
- Recurrent in vitro fertilization (IVF) failure is often associated with immune dysregulation, specifically an elevated Th1/Th2 cytokine production ratio.
- Intravenous immunoglobulin (IVIG) combined with anti-tumor necrosis factor-alpha (anti-TNF-α) therapy has been explored as a treatment for these patients.
Purpose of the Study:
- To critically analyze the evidence for a causal relationship between IVIG + anti-TNF-α treatment and improved IVF outcomes in patients with elevated Th1/Th2 ratios.
- To evaluate the impact of this combined therapy on delivery and live birth rates in women with recurrent IVF failure.
Main Methods:
- A cohort-controlled study design was employed.
- Critical analysis of the evidence for causation was performed, focusing on the nature of the observed results.
- Patient outcomes, including delivery rate and live birth rate per embryo, were compared based on the degree of Th1/Th2 ratio correction.
Main Results:
- Patients whose elevated Th1/Th2 ratio normalized demonstrated significantly better delivery and live birth rates compared to those with incomplete correction.
- The observed outcomes approached the estimated maximum possible rates, strengthening the argument for treatment efficacy.
- Maximal improvement was noted when treatment was administered 61-120 days prior to embryo transfer, suggesting a mechanism related to improved follicular physiology.
Conclusions:
- The study provides strong evidence for a causal link between IVIG + anti-TNF-α therapy and improved IVF success in patients with elevated Th1/Th2 ratios.
- Independent replication is recommended to further augment the statistical power and confirm these findings.
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