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Causes of male infertility

Authors
Bradley D Anawalt, MD
Stephanie T Page, MD, PhD
Section Editor
Alvin M Matsumoto, MD
Deputy Editor
Kathryn A Martin, MD

INTRODUCTION

The fertility rate in a couple is influenced by several factors, including the age of each partner; exposure to environmental toxins, drugs, or radiation; severe systemic disease in either partner; and the specific disorders described below.

The causes of male infertility will be reviewed here. The evaluation and treatment of male infertility and issues related to unexplained infertility are discussed separately. (See "Evaluation of male infertility" and "Treatment of male infertility" and "Unexplained infertility".)

EPIDEMIOLOGY

Infertility in a couple is defined as the inability to achieve conception despite one year of frequent, unprotected intercourse. (See "Overview of infertility", section on 'Definitions'.)

The distribution of male and female causes of infertility has not been well defined. In a 1982 to 1985 World Health Organization (WHO) multicenter study, 20 percent of cases were attributed to male factors, 38 percent to female factors, 27 percent to both, and 15 percent not clearly to either [1].

While many men with male infertility have oligozoospermia (a low number of sperm cells in the ejaculate compared with reference ranges) or azoospermia (no sperm cells in the ejaculate), some infertile men have normal sperm counts [2].

                                

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Literature review current through: Jun 2017. | This topic last updated: Jun 30, 2017.
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