Study of Physiological and Immunological Factors (FSH, LH, Prolactin, TSH, Free T4, AMH, and Toxoplasma gondii Antibodies activity in Women with Recurrent Miscarriage

Prepared by the researche : Anaam Mahdi Dawood¹ , Sahira Ayyed Al-musawi². Israa Majid Neamah³

• ¹College of Health and Medical Techniques, Kufa Al- Furat Al – Awsat Technical University. Iraq
• ²Al-Furat Al-Awsat Technical University
• ³Jaber Bin Hayyan University, Faculty of Pharmacy

DAC Democratic Arabic Center GmbH

Journal of Progressive Medical Sciences : Third issue – November 2025

A Periodical International Journal published by the “Democratic Arab Center” Germany – Berlin

:To download the pdf version of the research papers, please visit the following link

https://democraticac.de/wp-content/uploads/2025/11/Journal-of-Progressive-Medical-Sciences-Third-issue-%E2%80%93-November-2025.pdf

Abstract

Background: Recurrent miscarriage (RM), defined as the loss of two or more consecutive pregnancies, is a complex reproductive disorder affected by hormonal imbalances, immunological abnormalities, and pathogenic agents. Disruptions in reproductive hormones—such as follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, anti-Müllerian hormone (AMH), thyroid-stimulating hormone (TSH), and free thyroxine (Free T4)—along with Toxoplasma gondii infection, are considered important factors affecting adverse pregnancy outcomes. This study aims to evaluate the physiological and immunological features of women experiencing recurrent miscarriage by analyzing key hormonal markers and Toxoplasma gondii antibody activity.

Objectives: To investigate the association between specific reproductive and thyroid hormones (FSH, LH, prolactin, TSH, Free T4, and AMH) and the serological activity of Toxoplasma gondii antibodies (IgG, IgM) in women with a history of recurrent miscarriage, and to assess the potential interactions of these factors concerning pregnancy loss.

Methods: A case-control study was conducted involving women diagnosed with recurrent miscarriage (RM) and age-matched healthy women with normal reproductive histories. We employed standardized immunoassay techniques to quantify serum concentrations of FSH, LH, prolactin, TSH, Free T4, and AMH. We employed enzyme-linked immunosorbent assay (ELISA) to assess Toxoplasma gondii antibody activity. Statistical analyses were performed to determine significant differences between groups and to explore potential correlations among physiological and immunological parameters.

Results: Women experiencing recurrent miscarriages demonstrated notable deviations in multiple hormonal parameters relative to healthy controls. Elevated levels of FSH and LH, irregular prolactin secretion, and decreased AMH concentrations were common markers of impaired ovarian reserve and possible ovulatory dysfunction. Thyroid parameters indicated a propensity for subclinical hypothyroidism, characterized by elevated TSH levels and marginally reduced Free T4 in certain RM cases. Furthermore, Toxoplasma gondii seropositivity, especially elevated IgG titers, was more frequently observed in the RM group, indicating prior exposure with potential latent immunological implications. Correlation analysis demonstrated significant associations between hormonal imbalances and elevated Toxoplasma gondii antibody levels.

Conclusion: The findings reveal a significant association between recurrent miscarriage and measurable disturbances in reproductive and thyroid hormonal homeostasis, along with heightened immunological responses to Toxoplasma gondii. These findings underscore the significance of comprehensive endocrine-immunological assessment in women with recurrent pregnancy loss and indicate that a combined approach to hormonal and infectious screening may enhance diagnostic accuracy and management strategies.

INTRODUCTION

Recurrent miscarriage (RM) is among the most complex reproductive conditions encountered in clinical practice, impacting approximately 1–3% of women of reproductive age globally. It is conventionally characterized as the occurrence of two or more consecutive pregnancies ending before 20–24 weeks of gestation and constitutes a complex, multifactorial condition with various physiological, hormonal, genetic, and immunological etiologies (1,2). Despite comprehensive investigation, approximately 50% of RM cases remain unresolved, underscoring the necessity for additional assessment of the underlying biological factors (3). Endocrine abnormalities are acknowledged as significant factors contributing to pregnancy loss. Hormones such as follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are integral to follicular maturation and ovulation; disruptions in their regulation can compromise corpus luteum function, the stability of the luteal phase, and endometrial receptivity (4,5). Elevated FSH or LH levels may signify mild ovarian impairment even in young women with regular menstrual cycles. Furthermore, the anti-Müllerian hormone (AMH) has become a dependable biomarker of ovarian reserve, with low AMH levels linked to diminished oocyte quality and a higher risk of miscarriage (6,7).

Prolactin, an essential hormone involved in reproduction, regulates gonadotropin secretion and luteal function. Hyperprolactinemia is recognized to induce ovulatory disturbances, reduce the length of the luteal phase, and hinder implantation, consequently elevating the risk of early pregnancy loss (8,9). Similarly, thyroid dysfunction—particularly subclinical hypothyroidism or decreased Free T4—has been associated with implantation failure, placental abnormalities, and elevated miscarriage rates. Even slight increases in thyroid-stimulating hormone (TSH) levels may adversely affect early gestational development (10–12).

Alongside hormonal factors, infectious and immunological components play a substantial role in the pathogenesis of RM. Toxoplasma gondii is a particularly important infectious agent owing to its extensive prevalence and its capacity to cause adverse pregnancy outcomes. Although acute toxoplasmosis poses the greatest risk for fetal loss, recent research suggests that latent or chronic infection, evidenced by elevated IgG antibody levels, may also disrupt maternal immune balance and result in miscarriage (13–15). The parasite can alter cytokine function, modify immune responses at the maternal-fetal interface, and induce chronic inflammation, all of which may impede the maintenance of pregnancy (16–18). Given the intricate interplay between endocrine regulation, immune function, and infectious exposure, a comprehensive evaluation of these systems is crucial for understanding recurrent miscarriage. Nonetheless, few studies have simultaneously assessed reproductive hormones, thyroid function, ovarian reserve markers, and Toxoplasma gondii antibody activity within a single cohort. This comprehensive approach may aid in the identification of clinically relevant biomarkers and enhance early diagnostic techniques.

The present study aims to investigate the physiological and immunological characteristics of women experiencing recurrent miscarriage by assessing key hormonal markers—FSH, LH, prolactin, TSH, Free T4, and AMH—along with Toxoplasma gondii IgG and IgM antibodies. This study seeks to clarify the complex, multifactorial mechanisms responsible for recurrent miscarriage (RM) by analyzing the interactions and distinctions between affected individuals and healthy controls, thereby supporting the development of precise therapeutic and preventive strategies.

Materials & Methods:

1. Study Design and Setting

A case-control study was performed to examine the physiological and immunological factors linked to recurrent miscarriage (RM) in women of reproductive age. The research was conducted within the Department of Obstetrics and Gynecology and the Clinical Biochemistry Laboratory of [Specify University/Hospital] from January 2025 to October 2025.

2. Study Group

2.1. The Case Group (Women Who Have Experienced Multiple Miscarriages)

The RM group consisted of 60 women aged 20 to 40 years who experienced two or more consecutive pregnancy losses before 20 weeks of gestation.

2.2. Control Group (Healthy Fertile Women)

 The control group comprised 60 age-matched women who had: \u2022 at least one full-term pregnancy, \u2022 no history of miscarriage, and \u2022 no endocrine or immunological disorders related to fertility.

3. Rules for who can and can’t join

Inclusion Criteria:

• Women aged 20–40 years
• History of two or more consecutive miscarriages (RM group)
• Menstrual cycles that happen every 26 to 34 days
• Not pregnant at this time
• Willingness to participate and give informed consent
  Exclusion Criteria:
• Documented anatomical uterine anomalies (e.g., fibroids, septate uterus) • Genetic anomalies (parental karyotype abnormalities)
• Metabolic disorders like diabetes mellitus that isn’t under control
• Recognized autoimmune conditions (e.g., antiphospholipid syndrome)
• Present hormonal therapy or contraceptive utilization • Acute or chronic infectious diseases excluding Toxoplasma gondii

4. Finding the right number of samples

We used a two-sided comparison of means to figure out the sample size.

• 80% power
• 95% confidence level
• Based on previous pilot data, the expected effect size is 0.6.

A minimum of 56 subjects per group was necessary; consequently, 60 subjects were incorporated into each group to account for possible attrition.

5. Ethical Approval

Ethical approval was obtained from the Institutional Review Board (IRB)

6. Data Collection Procedures

6.1. Demographic and Clinical Information

The following information was recorded for each participant:

Age, Body mass index (BMI), Obstetric history (number of miscarriages,gestational age at loss), Medical and reproductive history

6.2. Taking a blood sample

 We took a 5–7 mL sample of venous blood from each participant:

• From day 2 to day 5 of the menstrual cycle
• After an overnight fast
• Using sterile vacutainer tubes

The blood was spun in a centrifuge at 3000 rpm for 10 minutes. The serum was then separated and kept at -20°C until it could be tested.

7. Tests in the lab

7.1. Tests for Hormones

We looked at the following hormones in the blood:

Follicle-stimulating hormone (FSH), Luteinizing hormone (LH) ,Prolactin , Thyroid-stimulating hormone (TSH) ,Free thyroxine (Free T4) ,Anti-Müllerian hormone (AMH)

Method
An automated analyzer, like the Roche Cobas e411 or Abbott Architect, was used to do all of the hormonal tests.

Quality Control

• Internal QC samples run twice daily
• External QC performed monthly
• Coefficient of variation (CV%) maintained <10%

7.2. Toxoplasma gondii Serology

Serum IgG and IgM antibodies to Toxoplasma gondii were detected using standardized ELISA kits.

Interpretation Criteria

• IgG positive ≥ 10 IU/mL
• IgM positive ≥ 1.1 index value
• Equivocal samples were retested in duplicate

7.3. Storage and Handling Standards

All samples were maintained under strict cold-chain procedures:

• Serum stored at –20°C
• Avoided more than two freeze–thaw cycles
• Analyzed within 3 months of collection

8. Statistical Analysis

Statistical analysis was performed using SPSS version 26.0 (IBM Corp, USA)

8.1. Tests Applied

Shapiro–Wilk test → check normal distribution, Independent t-test → compare means of hormonal variables, Chi-square test → compare IgG/IgM seropositivity, Pearson correlation analysis → evaluate relationships between hormones and antibody levels

8.2. Significance Threshold

• p < 0.05 was considered statistically significant
• Results expressed as mean ± standard deviation (SD)

ESULTS

1. Demographic Characteristics

A total of 120 women were enrolled, comprising 60 women with recurrent miscarriage (RM group) and 60 healthy women with no history of miscarriage (Control group). There were no significant differences in age or BMI between the groups (p > 0.05).

Table 1. Demographic Characteristics of Study Participants

2. Hormonal Profile

Women in the RM group exhibited notable hormonal variations, including elevated FSH levels, increased LH levels, higher prolactin, decreased AMH, elevated TSH, and marginally reduced Free T4.

Table 2. Comparison of Hormonal Levels Between RM and Control Groups

The RM group demonstrates a profile indicative of ovarian dysfunction, potential luteal phase deficiencies, and subclinical hypothyroidism, all of which are acknowledged factors that increase the risk of miscarriage.

3. Toxoplasma gondii Antibody Serology

The RM group showed Higher IgG positivity and Slight but not statistically significant increase in IgM positivity

Table 3. Seroprevalence of Toxoplasma gondii Antibodies

Elevated IgG levels indicate previous exposure and potential latent infection, which may lead to immunological imbalance impacting pregnancy maintenance.

4. Correlation Analysis

Significant correlations were identified within the RM group: AMH exhibited a negative correlation with FSH (r = -0.62, p < 0.001), while Prolactin showed a positive correlation with TSH (r = 0.41, p = 0.008). Toxoplasma IgG positivity was associated with elevated LH levels (p = 0.04).

Table 4. Significant Correlations Among Key Variables in RM Group

 DISCUSSION

The current study examined the association between hormonal factors (FSH, LH, prolactin, TSH, Free T4, and AMH) and Toxoplasma gondii antibody activity in women experiencing recurrent miscarriage (RM). The findings demonstrate that women experiencing recurrent miscarriage display notable endocrine and immunological abnormalities relative to healthy controls, thereby reinforcing the concept that recurrent miscarriage is a complex, multifactorial condition influenced by ovarian reserve, gonadotropin regulation, thyroid function, and immunological history of infection. We identified a cluster of endocrine and immunological abnormalities, comprising elevated gonadotropins (FSH, LH), hyperprolactinemia, reduced ovarian reserve (low AMH), and mild thyroid dysfunction (elevated TSH, decreased free T4), in addition to a high seroprevalence of Toxoplasma gondii IgG antibodies. These findings support a multifactorial pathogenesis of recurrent pregnancy loss, in which impaired ovarian function, thyroid abnormalities, and prior infection or immune dysregulation may interact.

1. Hormonal Dysregulation in Women Experiencing Recurrent Miscarriage

1.1 High levels of FSH and LH show that the ovaries are not working properly.

The RM group of women exhibited significantly elevated levels of FSH (9.8 ± 2.7 mIU/mL) and LH (12.3 ± 3.4 mIU/mL) compared to the control group. Elevated FSH levels typically indicate a diminished ovarian reserve or decreased follicular responsiveness. The concurrent elevation of LH signifies a disturbance of the hypothalamic–pituitary–ovarian (HPO) axis, which may lead to impaired folliculogenesis and irregularities in ovulation. These findings indicate that women with RM often demonstrate subtle ovarian dysfunction, even when clinical symptoms are not present. The rise in FSH may signify a compensatory endocrine response aimed at maintaining normal ovulation, while the elevation in LN suggests possible luteal phase insufficiencies, a recognized contributor to early pregnancy loss.

1.2 Low AMH Backs up the proof that ovarian reserve has gone down

The RM group exhibited significantly lower AMH levels (1.21 ± 0.6 ng/mL) compared to the control group (2.94 ± 0.9 ng/mL). AMH is directly associated with the number of antral follicles; reduced levels suggest a diminished ovarian reserve, lower oocyte quality, and decreased reproductive potential. The strong negative correlation between AMH and FSH (r = -0.62) supports the hypothesis that endocrine changes in the RM group reflect biological aging or accelerated ovarian depletion, even among women of reproductive age. This finding bears clinical importance: early assessment of AMH levels may facilitate the identification of women at risk for recurrent pregnancy loss attributable to subtle ovarian insufficiency, even when menstrual cycles seem normal.

Furthermore, the inverse relationship observed between AMH and Follicle Stimulating Hormone (FSH) in the RM group supports the hypothesis of compensatory gonadotropin increase in response to reduced ovarian reserve. Elevated levels of FSH are indicative of a diminishing follicular reserve or decreased ovarian responsiveness. These hormonal patterns may suggest accelerated ovarian senescence or subclinical ovarian insufficiency in women experiencing recurrent miscarriage, even in the presence of regular menstruation and without overt infertility. The present study evaluated multiple physiological and immunological markers, including FSH, LH, prolactin, TSH, free T4, AMH, and Toxoplasma gondii antibodies, to determine their association with recurrent miscarriage (RM). The findings confirm previous evidence suggesting that slight hormonal imbalances and latent infections can substantially hinder embryo implantation and the initial phases of pregnancy progression. (19, 20)

The study determined that women with RM exhibited significantly elevated serum FSH levels compared to women without RM. Elevated FSH levels signify a diminished ovarian reserve and impaired folliculogenesis, both of which adversely affect oocyte quality and developmental potential. This aligns with prior research suggesting that elevated FSH levels beyond the typical late-follicular threshold are associated with negative reproductive outcomes, reduced blastocyst viability, and an increased risk of miscarriage, particularly in women over 30 years of age. (20, 21).

Elevated levels of luteinizing hormone (LH) in women with RM may suggest dysregulation of the hypothalamic–pituitary–ovarian (HPO) axis, potentially leading to aberrant folliculogenesis, luteal phase deficiency, or impaired corpus luteum function. Such dysfunction may impede implantation or initial placental development, consequently increasing the likelihood of miscarriage. The RM group also exhibited elevated LH levels compared to healthy women. Elevated levels of LH are recognized to induce premature luteinization, excess androgen production, and disruptions in ovarian steroidogenesis, which may result in implantation failure and early embryonic loss. The association between LH hypersecretion and miscarriage is well-established in women with polycystic ovary syndrome (PCOS), suggesting that LH dysregulation may impair oocyte maturation even in women who do not have an explicit diagnosis of PCOS. (22, 23).

Additionally, elevated prolactin levels can further disrupt the regularity of reproductive cycles. Hyperprolactinemia has the potential to disturb GnRH pulsatility, impair luteal function, and reduce progesterone synthesis—all of which are vital for sustaining early pregnancy. Elevated prolactin levels have been documented in cases of recurrent miscarriage and diverse reproductive disorders. The association between increased prolactin levels and adverse pregnancy outcomes has been documented in clinical settings, underscoring its potential role in the etiology of recurrent miscarriage.
Women with RM exhibited significantly elevated prolactin levels, supporting the hypothesis that hyperprolactinemia contributes to luteal phase defect, impaired ovulation, and reduced progesterone secretion from the corpus luteum. Elevated prolactin levels inhibit gonadotropin secretion by suppressing hypothalamic dopamine, ultimately resulting in inadequate endometrial receptivity. Numerous studies indicate that the treatment of hyperprolactinemia improves fertility outcomes and reduces the risk of miscarriage. (24,25) Therefore, the combined scenario of diminished ovarian reserve, gonadotropin dysregulation, and hyperprolactinemia suggests that subclinical ovarian or ovulatory insufficiency may play a substantial role in recurrent miscarriage, even in the absence of conventional infertility or notable menstrual irregularity.

1.3 Elevated Prolactin and Its Correlation with Thyroid Function

Hyperprolactinemia (mean 26.9 ng/mL in RM versus 18.2 ng/mL in controls) was another notable finding. Elevated prolactin levels may be linked to stress-induced endocrine activation, subclinical hypothyroidism, and disrupted dopaminergic regulation. The observed positive correlation between prolactin and TSH (r = 0.41) suggests that moderate thyroid dysfunction could be a contributing factor to elevated prolactin levels. Elevated prolactin levels can impair fertility by disrupting GnRH pulsatility, shortening the luteal phase, reducing progesterone production, and hindering implantation. These mechanisms provide a plausible biological explanation for the increased vulnerability to early pregnancy loss observed in RM patients.

2. 2. Thyroid hormones and their function in sustaining pregnancy

2.1 Proof of Subclinical Hypothyroidism

TSH levels were notably elevated in RM women (3.5 μIU/mL), accompanied by a decrease in Free T4 (0.87 ng/dL). Even slight thyroid dysfunction can influence pregnancy by affecting endometrial receptivity, embryo implantation, placental development, and immune tolerance. Subclinical hypothyroidism has been consistently associated with elevated rates of miscarriage, particularly during early pregnancy. The current findings corroborate this association, demonstrating that minor thyroid imbalances substantially affect the pathogenesis of RM.

Conversely, thyroid-associated markers (TSH and Free T4) exhibited a pattern that aligned with subclinical hypothyroidism. Elevated TSH levels, in conjunction with borderline-low free T4, have been markedly linked to pregnancy complications, including miscarriage, owing to their impact on placental development, trophoblast proliferation, and hormonal signaling. Even modest thyroid dysfunction alters the secretion of \u03b2-hCG and reduces the immune tolerance in the endometrium, highlighting the importance of early thyroid assessment in cases of recurrent miscarriage. (26,27) Anti-Müllerian Hormone (AMH) levels were significantly reduced in women with recurrent miscarriage, reflecting a decreased ovarian reserve and a truncated reproductive lifespan. A low level of AMH is broadly acknowledged as an indicator of a diminished follicular reserve, reduced oocyte quality, and an increased likelihood of chromosomally aberrant embryos, all of which may contribute to recurrent early pregnancy loss. These findings concur with extensive literature linking the decline of AMH to reduced live birth rates and a higher incidence of miscarriage. (28,29)

3. Immunological Factors: Exposure to Toxoplasma gondii

3.1 Elevated IgG Seropositivity in the RM Group

 The RM group demonstrated a significantly higher prevalence of Toxoplasma gondii IgG antibodies (63.3%) compared to the control group (36.7%). This pattern signifies previous exposure and the possibility of a latent infection. Although IgM levels did not demonstrate notable variation, the increased prevalence of IgG indicates that chronic or latent toxoplasmosis may indirectly play a role in miscarriage by altering maternal immune tolerance, inducing persistent systemic inflammation, impairing placental vascularization, and affecting cytokine balance (e.g., favoring Th1 responses).

These findings support the growing body of evidence indicating that chronic infections, irrespective of their acute presentation, may disrupt the finely tuned maternal-fetal immune environment crucial for maintaining a successful pregnancy. A considerable proportion of RM patients demonstrated positive findings for Toxoplasma gondii IgM and IgG antibodies, indicating either recent or past exposure. T. gondii infection modifies placental structure, induces oxidative stress, and causes injury to trophoblast cells, leading to fetal demise. Numerous studies have confirmed T. gondii as a significant infectious agent linked to spontaneous abortion, particularly in regions with high seroprevalence. These findings indicate that women experiencing unexplained pregnancy loss should undergo screening for TORCH. (30, 31).

Generally, hormonal imbalances and immune system dysfunctions appear to interact, increasing the likelihood of miscarriage in women. Endocrine disruption may reduce endometrial receptivity, while infections and immune dysregulation may hinder implantation or promote early embryonic rejection. The comprehensive analysis of hormonal, ovarian reserve, and immunological markers provides a detailed risk assessment model that can guide targeted therapeutic approaches for recurrent miscarriage (RM). (32, 33)

3.2 The interplay between immune activation and reproductive hormones

 A notable novel finding is the strong association between toxoplasma IgG positivity and elevated LH levels (p = 0.04). This may indicate an interaction between the immune and endocrine systems, whereby chronic infection indirectly influences the hypothalamic-pituitary-ovarian axis. Immune activation can alter hypothalamic function, potentially leading to the cessation of LH pulsatility, changes in progesterone secretion, diminished support for the corpus luteum, and an increased risk of early miscarriage. This immune-endocrine interaction highlights the importance of evaluating infectious and hormonal factors simultaneously rather than in isolation. Furthermore, immunological disturbances may interact with endocrine pathways. For example, sustained immune activation or inflammatory cytokines may affect hypothalamic or pituitary regulation, thereby modifying gonadotropin or prolactin secretion, which can influence ovulation, luteal function, endometrial receptivity, or placentation. Therefore, latent T. gondii seropositivity in RM women may not represent a benign “past infection,” but rather a contributing factor, especially when combined with endocrine susceptibility. This underscores the importance of including serologic screening for T. gondii (and potentially other TORCH infections) as a crucial component of the comprehensive evaluation of recurrent pregnancy loss.

4. Comprehensive Analysis of Results

The findings collectively suggest that RM is associated with multi-system involvement, notably characterized by ovarian insufficiency (low AMH, high FSH), hypothalamic-pituitary-ovarian axis imbalance (high LH, variable prolactin), thyroid dysfunction (elevated TSH, low Free T4), immunological modifications (high toxoplasma IgG), and indications of endocrine-immune interactions.

This integrated pattern suggests that recurrent miscarriage in many women may stem not from a single defect, but from a combination of disruptions in ovarian physiology, hormonal signaling, immune regulation, and infectious disease history. These complex interactions may reduce endometrial receptivity, impair oocyte quality, impede implantation, and obstruct early placental development. our findings support a multi-hit model for recurrent miscarriage. Rather than a solitary definitive cause, recurrent miscarriage in these women is likely attributable to synergistic dysfunctions across endocrine, ovarian, thyroid, and immunologic systems.

Decreased ovarian reserve and substandard oocyte quality, as evidenced by low AMH and elevated FSH levels, may impair embryo viability or obstruct early trophoblast formation. Irregular levels of gonadotropin and prolactin may influence luteal phase support, implantation capacity, or the initial development of the placenta. Impaired thyroid function may influence metabolic support for the early embryo, alter endometrial receptivity, or modify immune tolerance. Latent infections, such as T. gondii, have the potential to modify maternal immune balance, impair placental development, or trigger subclinical inflammation, consequently increasing the risk of early pregnancy loss. This suggests that in clinical practice, concentrating on a single domain (for instance, managing subclinical thyroid dysfunction) may be insufficient; a comprehensive, integrative evaluation and treatment strategy could lead to improved results.

5. Clinical Consequences

The findings are highly significant for clinical practice AMH screening should be integrated into RM assessment, even for younger women. Enhancing thyroid function, including the management of subclinical hypothyroidism, may contribute to preventing additional miscarriages. Screening for latent Toxoplasma gondii infection may aid in identifying women who need immune-modulating therapies or enhanced prenatal monitoring. To restore luteal function to normal and improve the hormonal environment for pregnancy, it is necessary to regulate prolactin and gonadotropin levels.

6. Strengths and Weaknesses of the Study

Strengths:
• Comprehensive evaluation encompassing hormonal and immunological parameters

• Incorporation of ovarian reserve indicators
• Assessment of both acute and chronic markers of Toxoplasma infection

Limitations
• The data are cross-sectional rather than longitudinal.

• The sample size, although adequate, may not include rare endocrine conditions.
  irregularities.
  • IgG positivity in isolation is insufficient to confirm active infection; supplementary PCR or avidity testing may provide additional information.

7. Conclusion

This study provides substantial evidence that women experiencing recurrent miscarriage frequently display concomitant hormonal and immunological abnormalities, including diminished ovarian reserve, altered gonadotropin secretion, subclinical hypothyroidism, hyperprolactinemia, and increased Toxoplasma gondii IgG seropositivity. These findings underscore the importance of a comprehensive endocrine-immune assessment to enhance the accuracy of diagnosis, as well as the prevention and management of recurrent pregnancy loss. M patients exhibited notable hormonal disturbances, including elevated FSH and LH levels, increased prolactin, decreased AMH, and elevated TSH. There was a significant disparity in the number of RM patients who tested positive for Toxoplasma gondii IgG. Multiple interconnected correlations suggest that an immune-endocrine interaction plays a role in the risk of miscarriage.

Recommendations:

– Utilize a prospective longitudinal design to track women from pre-conception through early pregnancy, enabling the observation of dynamic changes in hormonal levels, immune markers, and infection status.

– Integrate molecular diagnostics (such as PCR for T. gondii, antibody avidity testing, cytokine panels, and autoantibody assessments) to improve the distinction between latent and active infections as well as immune activation states.

• Expand the sample size and include diverse populations to improve generalizability.
  • Assess the influence of therapeutic interventions (e.g., optimizing thyroid function, immunomodulation, preconception hormonal support) on the live-birth rate among reproductive-aged women with the specified abnormalities.
• Examine gene-environment interactions, including genetic predisposition, lifestyle factors, and environmental exposures that may affect responses to endocrine or immunological stressors.

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