How to Interpret Semen Analysis Results: What every Gynecologist and General Practitioners Should Know

Infertility is defined as the inability to conceive after at least one year of regular, unprotected sexual intercourse [1] and affects one out of eight couples of reproductive age in the United States. Estimates suggest that a significant percentage of such cases result from defective semen quality in the male [2]. The analysis of an ejaculate is relatively simple to perform and often requested before or at the same time complicated and expensive examination of the female is conducted. 

Most initial semen analysis requests are from gynecologists, general practitioners and family practitioners who wish to advise their patients regarding their fertility status. As a health care provider, you should be able to interpret the basic semen analysis results. Although literature is full of description of semen analysis methods, it does not explain the technical rationale for conducting semen analysis in relation to the corresponding sperm activity within the female reproductive system. 

Briefly during coitus, semen is deposited within the vagina, near and around the cervix, sperm then has to penetrate and migrate through the cervical mucus to reach the site of fertilization. As a prerequisite for fertilization, sperm must undergo strict physiological modifications during transit through the female reproductive tract, known as “capacitation”. Once sperm have reached the ovum, it has to negotiate through the oocytes cumulus oophorus and corona radiata which is facilitated by the acrosome reaction. Following fusion with the oocyte it has to undergo nucleus decondensation, fusing with the female chromatin materials to form a full complement of chromosomes finally resulting in an embryo. 

The primary goal of semen analysis is to determine whether or not an ejaculate has a sufficient number of potentially fertile sperm to achieve the desired outcome of conception. There is a need to find out whether the sperm can get to the fertilization site through the cervical mucus. This will be the fundamental requirement for requesting semen analysis. Physically being able to reach the fertilization site within the female reproductive tract is of primary importance, facilitated by such factors as sperm motility and sperm morphology. Similarly, the statistical improbabilities of finally reaching the oocyte necessitate sufficient sperm numbers within any given ejaculate, a variable determined by sperm concentration. 

World Health Organization [3] recommends at least 15 million spermatozoa per ml, 40% overall sperm motility with a minimum of 32% progressive sperm motility and normal sperm forms of 4% or more for an ejaculate to be acceptable. They also advices that the total number of spermatozoa, total normal sperm forms and total normal motile sperm are important factors to consider. Hence semen volume is essential. It is recommended that at least a minimum of 1.5ml per ejaculate is considered acceptable. One should familiarize common terminology and its meaning when interpreting the results of semen analysis [4]. When an ejaculate that satisfies the acceptable level of sperm parameters analyzed, is referred to as “Normozoospermia” or “Normozoospermic” ejaculate. 

If no ejaculate is obtained following masturbation then it is referred to as “Aspermia”. This is probably due to retrograde ejaculation; a condition where the ejaculate flows backwards into the urinary bladder during orgasm. If the ejaculate volume is low, less than 0.5ml it is referred to as “Hypospermia” it is usually brought about by anxiety, stress, disapproval and embarrassment about masturbation or congenital bilateral absence of the vas deferens. If the ejaculate volume is high then it is referred to as “Hyperspermia” probably due to long period of sexual abstinence or overproduction of accessory sex gland fluid. 

Complete absence of sperm in an ejaculate is referred to as “Azoospermia” or “Azoospermic” ejaculate and may be present in about 1% of all men and in approximately 15% of men being evaluated for infertility [5]. It is probably due to obstruction of the ejaculatory duct, genetic causes or hormonal. Sperm concentration below the acceptable level is referred to as “Oligozoospermia” or “Oligozoospermic” ejaculate. 

Sperm motility below the acceptable level is referred to as “Asthenozoospermia” or “Asthenozoospermic” ejaculate and complete absence of sperm motility is referred to “Necrozoospermia” and may be present in 0.2-0.48% of men being evaluated for infertility. If the normal forms are less than 4% then it is referred to as “Teratozoospermia” or “Teratozoospermic” ejaculate. Of course there can be combination of abnormalities such as “Oligoastheno”, “Oligoterato”, “Asthenoterato” and “Oligoasthenterato” -zoopermic ejaculates. 

Many women conceive with little or no problem even if their spouses have unusual or abnormal semen characteristics [6]. The standard sperm parameters used to indicate the fertility status of an ejaculate - sperm concentration, sperm motility and sperm morphology - have significant limitations as fertility indicators unless they are highly abnormal. But they do provide basic information for a health care worker to be able to advice the patient appropriately. 

It is well established that the ejaculate quality is highly variable, even between samples from the same individual since it is dependent on the extent of sexual stimulation, and the duration of sexual abstinence prior to ejaculation. Since sperm are continuously produced, the ejaculate may comprise of sperm of different ages. Routine semen analyses therefore should be performed at least twice. If these findings suggest abnormal, inconsistent or questionable sperm quality, regardless of the spouse clinical evaluation outcome, the patient should be referred to a reproductive urologist or reproductive endocrinologist for further evaluation.

1. Zegers-Hochschild F, Adamson GD, Dyer S, Racowsky C, de Mouzon J, et al. (2017) The International Glossary on Infertility and Fertility Care, 2017. Fertil Steril 108: 393-406.
2. https://www.cdc.gov/reproductivehealth/infertility/
3. World Health Organization (2010) WHO laboratory manual for the examination and processing of human semen (6thedn). WHO Press, Geneva, Switzerland.
4. Jeyendran RS (2000) Interpretation of Semen Analysis Results: A Practical Guide. Cambridge University Press, Cambridge, UK.
5. Lecomte PJ, Barthelemy C, Nduwayo L, Necrospermia HS (1999) Etiology and Management. In: Hamamah S, Olivennes F, Mieusset R, Frydman R (eds.). Male Sterility and Motility Disorders. Springer, New York, USA.
6. de Castro M, Jeyendran RS, Zaneveld LJ (1990) Hypo-osmotic swelling test: Analysis of prevasectomy ejaculates. Arch Androl 24: 11-16.