Epidemiology of Infertility

Background: The aim of epidemiologic research is to study the distribution and determinants of disease in human popula-tions with the intention of prevention and treatment of disease. Infertility is a condition of the reproductive system defined as not conceiving after 12 months of regular and unprotected sexual intercourse which have a pervasive adverse impact on the whole family and reproductive health. Female Infertility is classified into primary or secondary. Primary infertility re-fers to women who have never been diagnosed with a clinical pregnancy and meets the criteria of being classifiied as having infertility . Secondary infertility refers to women who are un-able to establish a clinical pregnancy but have previously been diagnosed with a clinical pregnancy. The goal of this article is to provide an overview of epidemiology and infertility.Materials and Methods: A literature review search was con-ducted through PubMed.Results: In addition to the advanced maternal age at concep-tion which is the most important negative predictive factor of fertility, other factors including lifestyle and environmental fac-tors are postulated to play an active role. Nearly, 8-12 % of all couples suer from infertility, the majority of them live in developing countries. Secondary infertility is the most common type of female infertility in worldwide due to post-abortive and postpartum infections. Most pregnancies (80%) occur within the first six cycles of attempted conception with regular inter-course. After six unsuccessful cycles with fertility, half of the remaining 20% of couples will conceive spontaneously in the next six cycles. After that, 10% of the couples are defiined as in-fertile, however, approximately 55% of them become pregnant in the next 36 months. After 48 months, about 5% of the cou-ples have absolute infertility (no chance of achieving a spon-taneous pregnancy). Evidence from review studies documents the alarming global decline of age-related fertility due to the increase of the average age of first-time mothers (between the ages of 30 and 35 or older) and the median age at last birth for females (40–41 years). The data of a study on female age at last birth in a natural fertility population shows that the age-related impaired fertility gradually increases from 4.5% at age 25 years to 20% at age 38 years. Afterward, it rises quickly to about 50% at age 41, 90% at age 45 years and approximately 100% at age 50 years. It reflects the fact that many women are still unaware of postponing childbearing as an important risk factor for fertil-ity. According to the reports of the studies, the true incidence of male infertility is unknown and the prevalence has been weakly estimated in various studies. Ignoring the differences in these research methodologies, there are wide variations in the pub-lished data on the prevalence of male infertility ranges from 6% to 50%. Not determining male infertility as a reportable disease, diagnosing and treating male infertility in an outpatient clini-cal setting, not reporting male infertility on insurance billing (it is paid out of pocket) are some of the factors mentioned in the studies that have impeded the epidemiology study of male infertility.Conclusion: This report summarizes current knowledge about epidemiology of female and male infertility.

کلیدواژه ها:

Epidemiology ، Female Infertility ، Male Infertility