Monday, December 22, 2008

Effect of advanced paternal age on fertility and pregnancy

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Effect of advanced paternal age on fertility and pregnancy

Angela Bianco, MD
Section Editor
Louise Wilkins-Haug, MD, PhD
Deputy Editor
Vanessa A Barss, MD

Last literature review version 16.3: October 2008 | This topic last updated: July 23, 2008 (More)

INTRODUCTION — Women are generally aware of the reproductive issues related to advanced maternal age, typically defined as 35 years of age or older on the estimated date of confinement. These issues include higher risks of infertility, fetal aneuploidy, gestational diabetes, preeclampsia, and stillbirth [1]. (See "Effect of advanced age on fertility and pregnancy in women").

Reproductive concerns related to advanced paternal age are less well defined [2]. Analysis of pregnancy outcome in the partners of these men is confounded by the fact that the partners are often of advanced maternal age.

FERTILITY — The probability of conception is primarily dependent upon maternal age, and to a lesser extent, paternal age. In contrast to oogenesis, which appears to be limited to the fetus in humans, spermatogenesis continues even in elderly men. Since the adult male's germ cells have passed through more mitotic replications than the adult female's germ cells, there is a greater opportunity for error. Increasing age has been associated with more breaks in sperm DNA, loss of apoptosis, and a higher frequency of point mutations [3,4]. (See "Male reproductive physiology").

A literature review on the association between male age and semen quality compared 30-year-old men to 50-year-old men and found decreases in semen volume (3 to 22 percent), sperm motility (3 to 37 percent), and percent of normal sperm (4 to 18 percent), but not sperm concentration, with age [5]. Similar findings were noted in a subsequent series that evaluated men age 22 to 80 years [6]. However, standard sperm parameters do not correlate perfectly with fertilizing capacity and achievement of pregnancy.

A more clinically useful approach to assessing the fertility of older men is to examine pregnancy rates and outcomes after attempting to control for the age of the female partner. These studies have reported conflicting results [7-11] and are limited by relatively small numbers of couples in whom the female partner is young and the male partner is old.

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