The effect of methyltestosterone on in vitro fertilization outcomes: A randomized clinical trial on patients with low ovarian response
Article information
Abstract
Objective
The aim of this study was to compare the outcomes of in vitro fertilization (IVF) in patients with a poor ovarian response who used methyltestosterone, versus those using a placebo, in an infertility clinic setting.
Methods
This clinical trial included 120 women who had undergone IVF with intracytoplasmic sperm injection due to poor ovarian reserve and infertility. The study took place at the Yas Infertility Center in Tehran, Iran, between January 1, 2018 and January 1, 2019. In the intervention group, 25 mg of methyltestosterone was administered daily for 2 months prior to the initiation of assisted reproductive treatment. The control group was given placebo tablets for the same duration before starting their cycle. Each group was randomly assigned 60 patients. All analyses were performed using SPSS ver. 23 (IBM Corp.).
Results
The endometrial thickness in the intervention group was 7.57±1.22 mm, whereas in the control group, it was 7.11±1.02 (p=0.028). The gonadotropin number was significantly higher in the control group (64.7±13.48 vs. 57.9±9.25, p=0.001). However, there was no significant difference between the two groups in the antral follicular count. The chemical and clinical pregnancy rates in the intervention group were 18.33% and 15% respectively, compared to 8.33% and 6.67% in the control group. The rate of definitive pregnancy was marginally higher in the intervention group (13.3% vs. 3.3%, p=0.05).
Conclusion
The findings of this study suggest that pretreatment with methyltestosterone significantly increases endometrium thickness and is associated with an increase in the definitive pregnancy rate.
Introduction
Assisted reproductive technologies (ART) have become a global cornerstone in the management of infertility [1,2]. However, despite significant scientific advancements in the field of ART, a persistent challenge remains: the suboptimal ovarian response observed in a substantial number of women undergoing in vitro fertilization (IVF). Poor ovarian response, which is estimated to occur in 9% to 26% of cases [1], is characterized by inadequate increases in estradiol (EST) levels, a reduced yield of retrievable oocytes, and a limited number of maturing follicles [2].
In the field of therapeutic interventions aimed at addressing this issue, endocrine modulation has shown significant promise. Although the usefulness of dehydroepiandrosterone (DHEA) and its derivatives has been the subject of numerous studies, recent research has shifted focus towards methyltestosterone [3,4]. As fan androgen, methyltestosterone has been proposed as a potential therapeutic agent that could improve pregnancy outcomes in women undergoing ART [5,6].
Previous studies have explored the intricate relationship between androgens and reproductive outcomes. For example, Vendola et al. [7] noted a direct stimulatory effect of testosterone on follicular maturation, which resulted in an increase in both follicular size and number. In contrast, the study conducted by Kara et al. [8] on DHEA did not identify any significant improvement in IVF-intracytoplasmic sperm injection (ICSI) outcomes for subjects with diminished ovarian reserve. In contrast, research by Barad and Gleicher [9] highlighted the potential of DHEA supplementation to increase both the number of oocytes and embryos.
Despite the extensive research conducted on various androgens, there remains a noticeable gap in our understanding of the definitive role of methyltestosterone. While androgens as a group have been thoroughly examined, the specific impact of methyltestosterone, particularly in the context of poor ovarian responders, has not been fully explored. The inconsistent results reported across different studies, coupled with the wide range of treatment protocols and dosages, underscore the need for a detailed understanding of the mechanistic and clinical implications of methyltestosterone.
With this backdrop, our study aimed to clarify this issue. We conducted a comparative analysis of IVF outcomes in women with documented poor ovarian response, comparing those treated with methyltestosterone to a placebo group. Our goal is to provide empirical evidence that could guide therapeutic strategies and inform clinical decisions.
Methods
1. Study design
This clinical trial study involved 120 women who had undergone IVF-ICSI due to poor ovarian reserve and infertility. The study took place at the Yas Infertility Center in Tehran, Iran, between January 1st, 2018 and January 1st, 2019. The study was conducted in strict accordance with the ethical guidelines set forth in the Declaration of Helsinki. The study protocol was thoroughly reviewed and subsequently approved by the Institutional Review Board of Tehran University of Medical Sciences (IR.TUMS.MEDICINE.REC.1397.035). Additionally, this clinical trial was registered under the IRCT code "IRCT20091012002576N16."
In this clinical trial, we utilized a single-blind design. Patients were not aware of the specific treatment they were receiving—either methyltestosterone or a placebo—but the attending physicians and medical staff had access to this information. The reasoning behind this approach was to ensure the delivery of optimal patient care. In situations where individualized medical decisions, adjustments, or interventions were required, it was paramount for the attending physicians to be aware of the exact treatment each patient was receiving.
We utilized a convenience sampling method for participant recruitment. Each patient referred to the Yas Infertility Center underwent evaluation based on the study's inclusion criteria. The center accepts patient referrals from all regions of Iran, providing us with a broad catchment area. This allowed us to secure a diverse patient population, thereby enhancing the generalizability of our findings.
We utilized OpenEpi software to calculate the sample size [10]. We employed balanced block randomization (with a block size of 4) to assign subjects to groups, resulting in 60 patients per group. The patients were then randomly divided into two groups. In the intervention group, prior to the commencement of fertility-aid treatment, a daily dose of a 25-mg methyltestosterone tablet (25-mg tablet; Abu-Riyhan Pharmacy) was prescribed for a duration of 2 months. Following this, the patients immediately began the fertility-aid cycle. Conversely, patients in the control group were given placebo tablets for 2 months before initiating the cycle.
2. Eligibility criteria
We included patients who met the following criteria: women aged 35 to 42 years with a poor ovarian response, an antral follicle count of less than 5, and a serum anti-Müllerian hormone (AMH) level of less than 1.2, as per the Poseidon criteria for poor ovarian reserve [11]. Patients with a history of ovarian surgery, systemic disease, thyroid disorders, renal or hepatic dysfunction, as well as ovum donors were excluded from the study.
All participants provided written consent and agreed to participate in the study. They were informed about the potential side effects of methyltestosterone, which may include acne, oily skin, weight gain, and excessive sweating.
3. Study procedure
In both groups, we measured follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, and thyroid hormones. For this study, we administered the standard protocol, which involved a daily dose of 300 U of gonadotropin FSH (Gonal-F; Merck Serono) starting on the second or third day of menstruation. Once the first 12-mm follicle was observed, we prescribed gonadotropin as a combination of FSH and LH (Merional; IBSA Slovakia). Starting from day 5 or upon observing a 14 mm follicle, we initiated a gonadotropin-releasing hormone antagonist at a dosage of 0.25 mg (CetrotideVR; Merck Serono). Each patient underwent sonography every 48 hours. Once the follicle measured between 18 and 20 mm, a prescription of 5,000 units of human chorionic gonadotropin was administered (Ovidrel1; Merck Serono Australia). Approximately 36 hours later, the patient's follicle was aspirated to retrieve the oocyte. Finally, we compared the number of oocytes obtained, the number of embryos, the number of embryos transferred, the number of FSH injections, the quality of eggs and embryos, and the pregnancy rates between the two groups.
4. Data analysis
Qualitative data are presented as frequency and percentage and quantitative variables are presented as mean±standard deviation. Categorical variables were compared using the chi-square test and continuous variables were compared using the Student t-test. All analyses were done using SPSS ver. 23 (IBM Corp.). A p-value less than 0.05 was considered to indicate statistical significance.
Results
Table 1 presents a comparison of patient age, duration of infertility, body mass index (BMI), and basal hormone serum concentrations between two groups. It is evident from the data that there was no significant difference between the two groups in terms of age, duration of infertility, and human chorionic gonadotropin levels. However, the mean BMI was significantly higher in the intervention group (23.45±3.03 kg/m2 vs. 21.09±3.4 kg/m2, p<0.001). Additionally, the cycle day 3 FSH and cycle day 3 EST levels were significantly higher in the intervention group. Conversely, patients in the control group exhibited higher cycle day 3 AMH levels (p<0.05).
Age, duration of infertility, BMI, and basal hormone concentrations in the intervention and control groups
Table 2 presents the previous history of IVF, gravidity, parity, and childbearing in the groups studied. While the control group had higher gravidity, the difference was not statistically significant. Specifically, 76.67% of patients in the intervention group had no history of gravidity, compared to 63.33% in the control group. However, this difference was not significant (p=0.20). Likewise, no significant differences were observed between the two groups regarding the number of previous IVF cycles, parity, and childbearing. Regarding embryo quality, as detailed in Table 3, there was no significant difference between the intervention and control groups.
Previous IVF, gravidity, parity, and childbearing history in the intervention and control groups
Quality of embryos in the intervention and control groups
After treatment, the endometrial thickness in the intervention group was 7.57±1.22 mm, with a minor increase of 0.40%, whereas in the control group it was 7.11±1.02 mm, showing a minimal change of 0.14% (p=0.028). The gonadotropin number in the control group was significantly higher posttreatment, at 64.7±13.48, compared to the intervention group's value of 57.9±9.25, with respective percentage changes of 3.52% and 3.98% (p=0.001). There was no significant difference between the two groups regarding the posttreatment antral follicular count (Table 4).
Comparison of study predictors (ET, AFC, and GN) between the intervention and control groups
As indicated in Table 5, the intervention group exhibited more favorable pregnancy outcomes. The rates of chemical pregnancy (18.33% vs. 8.33%, p=0.22) and clinical pregnancy (15% vs. 6.67%, p=0.25) were higher in the intervention group than in the control group, but these differences did not reach statistical significance. The rate of definitive pregnancy was also higher in the intervention group than in the control group (13.33% vs. 3.33%), a difference that is borderline statistically significant with a p-value of 0.05. Abortions were reported in three patients in each of the study groups.
Pregnancy outcomes in the intervention and control groups
Discussion
The findings of our study suggest that pretreatment with methyltestosterone significantly enhances endometrial thickness, which is associated with an increased definitive pregnancy rate.
Our study aligns with that of Nagels et al. [12], who demonstrated in a review study that pretreatment with testosterone may enhance live birth rates in women identified as poor responders undergoing ART. In recent years, the role of testosterone in ovarian function has garnered considerable interest. Historically, androgens were thought to have a negative impact on ovarian function. However, recent research has highlighted the importance of androgens, particularly in the early stages of follicle maturation [13,14]. The pattern of androgen receptor (AR) expression in the granulosa cells (GCs) of immature preantral and early antral follicles is particularly noteworthy. As the follicle matures, AR expression decreases, underscoring the importance of androgens during the initial stages of follicle development [13,14]. Many researchers now posit that androgens play a crucial role in follicular recruitment, promoting follicular growth, and reducing GC apoptosis, which in turn leads to an increase in the number of growing follicles [15]. A meta-analysis conducted by Noventa et al. [16] suggested an increase in the total number of oocytes, M2 oocytes, and total embryos following testosterone therapy.
In our study, the posttreatment endometrial thickness in the intervention group exhibited a slight yet significant increase compared to the control group. This finding aligns with previous studies suggesting a correlation between optimal endometrial thickness and improved IVF outcomes [17]. Furthermore, Andreeva et al. [15] reported in their study that extended testosterone pretreatment could potentially enhance IVF treatment in patients with low ovarian response. Their results demonstrated an increase in pregnancy rates, which is consistent with our findings. We observed a nearly significant difference between the patients who received testosterone pretreatment and the control group in terms of definitive pregnancy [15].
Patients with poor ovarian responses pose significant challenges in the field of reproductive medicine, as a universally successful treatment method has yet to be established. It is postulated that androgens are crucial in the early stages of follicle development, and a deficiency in these hormones may lead to a decrease in ovarian responsiveness to FSH [18]. Our research findings suggest that pretreatment with methyltestosterone can enhance fertility outcomes for those with diminished ovarian reserves. Identifying the specific group of poor responders who might benefit most from testosterone therapy would be advantageous in future research. We recommend comprehensive studies with larger sample sizes for further investigation.
While the sample size of 120 participants in our study may limit its broader generalizability, the diversity of our patient population, drawn from various regions of Iran, enhances its representativeness. Any potential biases arising from the single-blind design were mitigated through the standardization of procedures and rigorous data collection.
In conclusion, This study's findings suggest that pretreatment with methyltestosterone significantly increased endometrial thickness and was associated with a higher definitive pregnancy rate. However, it did not enhance chemical and clinical pregnancy outcomes compared to the control group. Consequently, we recommend conducting additional prospective randomized clinical trials with larger sample sizes to better understand the role of methyltestosterone in improving pregnancy outcomes.
Notes
Conflict of interest
No potential conflict of interest relevant to this article was reported.
Author contributions
Conceptualization: VHA, FDT, ZS. Data curation: FAA, ME. Formal analysis: FDT, ME. Funding acquisition: ZS. Methodology: FDT, ZS. Project administration: VHA, FDT, ZS. Visualization: FDT. Writing-original draft: FAA, ME. Writing-review & editing: VHA, FDT, ZS.
Acknowledgements
We gratefully acknowledge the kind support of the participants for their invaluable collaboration in this study, as well as the staff of Yas Hospital.