Published September 30, 2025 | Version v1
Journal article Open

The effect of low-dose naltrexone on immunological infertility in women with recurrent implantation failure

Authors/Creators

  • 1. Tikrit University, Tikrit, Iraq
  • 2. University of Tikrit, Tikrit, Iraq

Description

Recurrent implantation failure (RIF) is a considerable problem in assisted reproductive technologies, especially in the cases which are associated with immunological infertility. Low-dose naltrexone (LDN) has surfaced as a prospective treatment for several illnesses owing to its immunomodulatory characteristics.
The objective: to study the impact of LDN on the pregnancy course in women with immunological infertility and RIF.
Materials and methods. A total of 350 women aged 18–40 years with RIF and immunological infertility, who were exa-
mined and treated in the United Surgeons Fertility Center in Baghdad between January 1, 2024, and January 1, 2025, participated in the study. Participants were further divided into two groups. The treatment group included 175 women who received LDN 4.5 mg orally daily before pregnancy and during the first 12 weeks of pregnancy. The control group consisted of 175 women who did not receive naltrexone. The study examined clinical parameters such as endometrial thickness, ovarian follicular response, immune markers, and pelvic ultrasound findings.
Results. The group of women who received low doses of naltrexone had an increased endometrial thickness of 9.8 mm (26.9 mm vs 21.1 mm) compared to the control group. In the treatment group more mature follicles, better ovarian response, and better endometrium were determined. The treatment group also had lower concentrations of immune markers and antinuclear antibody levels than the control group. Pregnancy rates (pregnancy rate, number of successful embryo implantations, duration of pregnancy to 12 weeks) were greater in the treatment group than in the control group.
Conclusions. The results of the study indicate the prospect of implementing a new treatment method for women with immunological infertility and RIF. However, additional studies with a larger number of samples are needed to confirm the current efficacy and safety of LDN in the treatment of immunological infertility.

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https://repro-health.com.ua/article/view/341017

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