BEst Size for Ovulation Triggering in Poseidon 4 Patients (BEST 4 Study)

This observational clinical study aims to determine the optimal timing of ovulation triggering in women aged 35 and above with poor ovarian reserve.

For this purpose, cases undergoing ovarian stimulation for assisted reproductive treatment and planned final oocyte triggering will be evaluated in two separate groups:

1. \*\*Experimental Group\*\*: Final oocyte triggering will be performed when the follicle or follicles measure between 13-16 mm.
2. \*\*Control Group\*\*: Final oocyte triggering will be performed when the follicle or follicles measure greater than 17 mm.

All triggers will be administered uniformly with 6500 units of recombinant hCG and 0,2 mg triptorelin injections.

The primary outcome of the study will be the number of mature oocytes. Secondary outcomes will include fertilization rates, embryo counts, and implantation rates.

Primary and secondary outcomes will be compared between the two groups.

The timing of final oocyte maturation in assisted reproductive techniques is critically important. If serum steroid hormone levels are appropriate during the late follicular phase, ovulation triggering can be performed using various agents. There are numerous comparative studies in the literature on this topic.

However, a key issue is determining the most optimal timing for this trigger. In standard practice, the final triggering is performed when the follicle size reaches 17 mm or more.

The purpose of this is to obtain mature eggs from these follicles during the oocyte aspiration process.

However, in some special cases, to maximize the desired yield, this size threshold may be adjusted.

A prime example of this is in older patients with poor ovarian reserve, as the expected egg yield may not be achieved with standard practices.

During the oocyte collection process, fewer mature oocytes (M2) may be retrieved, or no oocytes may be retrieved at all, despite proper ovarian stimulation. Therefore, the optimal follicle size for these cases has not been definitively established in the literature. Thus, there is a need to determine other follicular thresholds specifically for older women with poor ovarian reserves to enhance egg and mature egg yields.

For this purpose, cases undergoing ovarian stimulation for assisted reproductive treatment and planned final oocyte triggering will be evaluated in two separate groups:

1. \*\*Experimental Group\*\*: Final oocyte triggering will be performed when the follicle or follicles measure between 13-16 mm.
2. \*\*Control Group\*\*: Final oocyte triggering will be performed when the follicle or follicles measure greater than 17 mm.

All triggers will be administered uniformly with 6500 units of recombinant hCG and 0,2 mg triptorelin injections.

The primary outcome of the study will be the number of mature oocytes. Secondary outcomes will include fertilization rates, embryo counts, and implantation rates.

Primary and secondary outcomes will be compared between the two groups.

Eligibility Criteria:
Inclusion Criteria:

Women age \&gt;35 years Women with low serum AMH (\&lt;1,2 ng/ml), low AFC (\&lt;5) Undergoing assisted reproduction with Short antagonist protocol Max daily gonadotropin dose of 300 IU

Exclusion Criteria:

* women with uterine and/or endometrial abnormality, women with endometrioma(s), short or long GnRH-agonist ovarian stimulation protocols, severe male infertiliy, genetic conditions, with normal ovarian reserve markers, \&lt;35 years old, women with prior ovarian surgeries, PGT-a cycles