Optimizing IVF Success: A Case Study of Melatonin-Assisted Frozen Embryo Transfer for Poor Oocyte Quality and Endometriosis

ABSTRACT

The case study investigates the journey of a couple facing infertility. It intensifies the challenges, including poor oocyte quality and endometriosis. In spite of two failed in vitro fertilization cycles, the decision for ovum pickup (OPU) was made, followed by intra-cytoplasmic sperm injection (ICSI), embryo treatment with melatonin, and frozen embryo transfer (FET) to optimize the chances of a successful pregnancy. The couple opted for this approach. OPU yielded four poor-quality oocytes, prompting ICSI and melatonin treatment to enhance embryo quality. The embryos were exposed to culture supplementation with melatonin for 72 hours before being transferred to conventional media. After 5 days or 120 hours, the embryos developed into 3BB quality blastocysts, indicative of developmental stage and morphology. The blastocysts were then cryopreserved, and after 2 months, FET was conducted, resulting in the transfer of two embryos, which subsequently led to a positive pregnancy indication, as indicated by a β-hCG level of 233 mUI/ml measured 14 days post transfer. This approach highlights the effectiveness of melatonin supplementation in improving embryo quality and ultimately facilitating successful pregnancy in complex scenarios like endometriosis-related infertility.

INTRODUCTION

Infertility is the failure to achieve pregnancy after 1 year of regular unprotected sexual intercourse. Factors related to the environment and lifestyle, such as smoking and obesity, can have a negative impact on fertility. Around 15% of infertile couples have unexplained infertility, while the remaining 85% of infertile couples have an identifiable cause. Male factor infertility, tubal disease, and ovulatory dysfunction are the most common causes of infertility. Ovulatory disorder contributes to around 25% of infertility cases, and around 75% of affected women diagnosed with polycystic ovary syndrome (PCOS).[1] Obesity negatively affects fertility; it can cause problems like irregular periods, chronic oligo-anovulation, and trouble getting pregnant. Obesity makes it more challenging to have a successful pregnancy and increases the chances of miscarriage.[2]

Endometriosis is a condition where tissue similar to the lining of the uterus grows outside of it. It causes chronic pain in many women, and it is a common condition associated with infertility.[3] Endometriosis poses a very big challenge to women’s reproductive health. The typical site where the endometriosis growth appears includes the ovaries and the lining of the pelvis. Additionally, endometriosis lesions may develop in other areas such as the vagina, abdominal wall, bladder, fallopian tubes, intestine, and cervix.[4] In 19–28% of cases of endometriosis, both ovaries are affected, while around 15–44% of females with endometriosis are unaware of its presence.[5] In women with endometriosis undergoing in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI), especially those with endometriosis larger than 3 cm, there is an increased number of immature oocytes. Also, endometriosis negatively impacts ovarian reserve.[6]

Furthermore, endometriosis may negatively impact oocyte quality, affecting maturation, morphological characteristics, and fertilization rates.[7] Endometriosis leads to various clinical issues such as inflammation, metabolic dysfunction, mood disorder, and increased cancer risk; it also causes pelvic pain, decreased work efficiency, and reduced quality of life. Oxidative stress, auto-immunity, and immune system dysregulation are the factors correlated with endometriosis. Melatonin, a natural molecule with anti-inflammatory and antioxidant properties, shows promise in managing endometriosis by inhibiting the modulating estrogen, proliferation, inflammation, and improving sleep quality.[8] Melatonin enhances the outcome of IVF embryo transfer (IVF-ET) by delaying ovarian ageing. Additionally, when added to in vitro culture, melatonin promotes oocyte maturation. Furthermore, it provides protection against mitochondrial injury in cases of PCOS.[9] This case presents the application of melatonin-assisted frozen embryo transfer (FET) for individuals with poor-quality oocytes and endometriosis.

CASE PRESENTATION

Patient information

A couple, facing challenges with conceiving naturally for over 4 years, sought help from an assisted reproductive technology (ART) clinic situated in the rural area of Wardha. The wife was 34 years old, while her husband was 37.

Medical history and physical examination

The couple had no prior medical or surgical history. However, the female partner used to consume combined birth control pills and work the night shift. Additionally, she was diagnosed with endometriosis. The female and male both had healthy body mass index (BMI) values, with the female at 22 kg/m² and the male at 26 kg/m².

Male and female investigation

Female

Follicle-stimulating hormone (FSH), anti-Mullerian hormone (AMH), luteinizing hormone (LH), progesterone, estrogen, and thyroid-stimulating hormone (TSH) tests were conducted to assess the hormonal levels. Estrogen was observed in the high range, while the progesterone level was found to be in the low range as displayed in Table 1. Additionally, structural abnormalities were assessed through ultrasound sonography, revealing no abnormalities. She had undergone two failed IVF cycles at another clinic.

Table 1.

Hormonal profile of female

Hormones	Observed level	Reference levels
Progesterone	9 ng/ml	10 ng/ml and more
TSH	1.3 mIU/L	0.4 – 2.34 mIU/L
AMH	2.2 ng/ml	1 – 4 ng/ml
FSH	5.3 IU/L	4.7 – 21.5 IU/L
Estrogen (Follicular phase)	424 pg/mL	30-400 pg/mL
Estrogen (Ovulation phase)	450 pg/mL	150-400 pg/mL
Estrogen (luteal phase phase)	309 pg/mL	30-300 pg/mL

Legend: ng/ml (nanograms per milliliter), mIU/L (milli-international units per liter), IU/L (international units per liter), pg/mL (picograms per milliliter)

Male

Hormonal tests, including LH and FSH, were conducted to examine the hormonal levels. Semen analysis was also performed to check sperm motility, morphology, count, and other semen parameters, as presented in Table 2. All the hormonal levels and semen parameters were found to be within the normal range representing good reproductive health.

Table 2.

Semen parameters of male

Parameter	Observed limit	Reference limit
Semen volume	1.7 ml	1.5–2.0 ml
Color	Opaque white	Opaque white
Viscosity	Liquified	Should liquify within 15–20 minutes
Count	90 mil/ml	15 million/ml or more
Progressive motility	38%	32% or more
Vitality	60%	58% or more
Normal Morphology	13%	4–14%
PH	7.4	7.2–7.4
Morphological defects	87%	96% or less

Legend: ml (milliliter), mil/ml (million per milliliter), pH (potential of hydrogen)

Diagnosis

A couple experiencing difficulty conceiving for the first time is a case of primary infertility. All factors of the male, including hormonal levels and semen parameters, were found to be within the normal range. However, the female was diagnosed with endometriosis, and her progesterone level was determined to be low.

Treatment

The couple had a history of two failed IVF cycles due to poor-quality oocytes. The causative factors of this might be endometriosis and altered levels of estrogen and progesterone, indicating difficulty in conceiving through regular conventional methods. To address these challenges, it was decided to perform ovum pickup (OPU), followed by ICSI, to treat embryos with melatonin, and then FET. To increase the chances of successful pregnancy, it was decided to freeze blastocysts for FET. FET was chosen over fresh embryo transfer due to its benefits, which include better coordination with the women’s natural menstrual cycle and more effective preparation of the uterine line to enhance the chances of implantation and successful pregnancy.

Later, the OPU was scheduled accordingly; the female partner underwent progesterone stimulation before the procedure. As planned, the OPU was performed, retrieving four oocytes of poor quality as presented in Figure 1. To address this problem, it was decided to proceed with ICSI and treat embryos with melatonin before conducting the FET. Melatonin, an antioxidant, reverses oxidative damage to oocytes and improves the embryo quality, the number of good-quality embryos, and fertilization rates.

Figure 1.

Poor-quality oocytes retrieved in OPU (ovum-pickup)

As planned, ICSI was performed, and the oocytes were injected with sperm. Subsequently, the embryos were cultured in culture media supplemented with 10–7 M melatonin for 72 hours. After this period, the embryos were taken out from the melatonin solution and transferred to conventional media for further growth over 48 hours. Exposure to melatonin is intended to enhance embryo development and increase the chances of producing good-quality blastocyst. After 120 hours (72 hours in melatonin and 48 hours in conventional culture media) or 5 days, the embryos developed into the two 3BB quality blastocysts; a grading system was used to assess the quality of embryos based on their developmental stage and morphology.

These embryos were then cryopreserved on two separate cryoprotecting straws (two on each straw). After 2 months, the female partner was prepared for embryo transfer. As per the plan, FET was performed, resulting in the transfer of two embryos. After transfer, the female partner was given rest for a few hours and then she was allowed to go home.

Follow-up

The female partner was advised to avoid heavy weight lifting and strenuous work. The female partner was advised to check her β-hCG level 14 days after embryo transfer, which revealed a positive indication of pregnancy with a level of 233 mIU/ml. She was prescribed some medicines and given instructions to follow. During her pregnancy, she was closely monitored to ensure compliance with the prescribed medications and instructions. Additionally, she was supervised for the rest of her pregnancy to ensure that she was following the medicines and instructions given to her.

DISCUSSION

The case presents a challenging scenario for the conception due to multiple factors including poor oocyte quality and endometriosis. The decision to proceed with OPU, ICSI, and FET seems appropriate given these challenges. The use of melatonin to improve embryo quality and the decision for FET over fresh embryo transfer were well founded. The successful formation of 3BB quality blastocyst after the melatonin treatment is promising as shown in Figure 2. In spite of this, careful monitoring and support are crucial throughout the process, considering the previous failure. The transfer of single embryos during FET reflects a wise approach to increase the chances of success while considering the potential risks and ethical considerations.

Figure 2.

Day 5 blastocyst (3BB quality) formed after melatonin treatment of Oocyte

In a study conducted by Fan et al.,[10] it was revealed that endometriosis adversely impacts oocyte quality through many factors, such as apoptosis, inflammation, oxidative stress, and steroidogenesis disorder in granulosa cells. Similarly, in a study conducted by Saito et al.,[11] it was revealed that endometriosis patients exhibit a higher incidence of apoptosis, increased oxidative stress, and alteration in the cell cycle compared to patients with other causes of infertility. Similarly, in our case, the quality of oocytes was reduced because of the endometriosis, causing the challenge in the treatment. In a study conducted by Lin et al.,[12] it was demonstrated that adding melatonin during prolonged in vitro maturation (IVM) improves oocyte quality and reduces reactive oxygen species (ROS) production and apoptosis. Furthermore, combining melatonin with both IVM and in vitro culture further enhances embryonic development and quality.

In a study conducted by Bao et al.,[13] it was demonstrated that supplementing the culture medium with melatonin increases the rate of good-quality embryos on day 3 for the patient with frequent poor-quality embryos. Moreover, it enhanced the blastocyst rate in vitrified warmed cleavage stage embryos. Similarly, in our case, when the embryos were treated with melatonin, a significant improvement in embryo quality was observed, ultimately resulting in a positive outcome.

CONCLUSIONS

In conclusion, in response to challenges involving poor oocyte quality and endometriosis, the couple opted for OPU, followed by ICSI and FET. Despite retrieving seven poor-quality oocytes during OPU, the embryos treated with melatonin developed into four 3BB-quality blastocysts, which were subsequently frozen. Following FET, the female partner obtained a positive pregnancy test result. This case highlights the efficacy of melatonin treatment in improving embryo quality and enhancing pregnancy rates in patients with endometriosis and poor-quality oocytes, thereby offering a promising approach in ART and reproductive medicine.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.