**3.2 Sperm freezing for patients with retrograde ejaculation and hypospermia**

Ejaculatory disorders could lead not only to psychological distress but may be the reason for 0.2–3% of infertility incidence in the couple. Co-ordination between epididymis, vas deferens, prostate, seminal vesicles, bladder neck and bulbourethral glands is required for the proper course of ejaculation. Various pharmacological, neurogenic or anatomic factors, disrupting the contraction of the bladder neck, may lead to retrograde ejaculation. In such cases semen is refluxed in the bladder and blends with the urine [14, 15]. As the urine normally has slightly acidic pH levels (average value - 6.0) compared to pH 7.1–8.0 of semen, the fusion of these fluids and pH fluctuations has adverse effect on spermatozoa [16]. Sperm cells retrieved from postejaculatory urine could be proceeded for assisted reproduction. Strict protocols for urine alkalization prior the procedure are mandatory. In some patients retrograde ejaculation results in hypospermia (abnormally low volume of less than 1.5 ml of the semen sample). Congenital absence of seminal vesicles and vas deferens, blockage of the ejaculatory duct, sympathetic nerves damage, and bladder neck surgery, insufficient levels of testosterone and short abstinence periods could also be the reason for hypospermia.

Retrograde ejaculation and hypospermia are linked to poor sperm parameters even cryptozoospermia. Freezing spermatozoa for fertility preservation in order to secure ART procedure would benefit any patient diagnosed with the described conditions.

#### **3.3 Sperm freezing for patients with diabetes**

Diabetes, a chronic autoimmune disease, is known to have detrimental effect to male fertility and sperm quality. Erectile dysfunction, retarded ejaculation and retrograde ejaculation could be persistent in patients with diabetes type 1 or 2. Reduced sperm quality and sperm DNA integrity impairment are also consequences to this health condition [17]. As all of the aforementioned are to affect fertility, cryopreservation of spermatozoa should be considered.

## **3.4 Sperm freezing for patients with Y-microdeletion and genetic aberrations**

Alterations in autosomal genes, specific mutations/deletions of several X- or Y-chromosome genes, microdeletions in the azoospermic factor (AZF) regions of the Y chromosome and chromosomal anomalies can cause spermatogenic failure and affect male fertility.

**Aberration in numerous autosomal genes result in fertility disturbance:**

SYCP3 (synaptonemal complex protein 3) - meiotic arrest and consequent azoospermia.

PLK4 (Polo-like kinase 4) – Sertoli cell only (SCO) syndrome.

NANOS1 (**Nanos C2HC-Type Zinc Finger 1)** – SCO syndrome and oligoasthenoteratozoospermia.

HSF2 (heat-shock factor protein 2) - idiopathic azoospermia.

TAF4B (**TATA-Box Binding Protein Associated Factor 4b) - azoospermia.**

*ZMYND15* **(Zinc Finger MYND-Type Containing 15) - azoospermia.**

SPATA16 (**Spermatogenesis-associated protein 16)** – globozoospermia.

KHLH10 (**Kelch Like Family Member 10)** – oligozoospermia. SEPT12 (septin 12) - oligoasthenozoospermia or asthenoteratozoospermia.

GALNTL5 (**Polypeptide N-Acetylgalactosaminyltransferase Like 5)** – asthenozoospermia.

AURKC (**Aurora Kinase C) -** large-headed polyploid spermatozoa or macrozoospermia.

Alterations in X-chromosome located genes and fertility disturbance:

TEX11 (**Testis Expressed 11)** - meiotic arrest and consequent azoospermia. RHOXF1 and RHOXF2/2B (human reproductive homeobox (RHOX) genes) severe oligozoospermia.

ANOS1 (**Anosmin 1)** - anosmin-1 is involved in the migration of neurons producing gonadotropin-releasing hormone (GnRH). The latter controls the production of several hormones triggered to sexual development before birth and at puberty.

*USP26* **(deubiquitinating enzyme gene) -** nucleotide variations in fertile and infertile men.

TAF7L (TATA-box binding protein associated factor 7) – reduced sperm count and motility, abnormal sperm morphology [18–20].
