 [ Symptoms ] what causes fertility problems [ Disease ] infertility has many causes that involve either the woman is the man is or both partners reproductive systems some causes include problems with the man is reproductive system problems with the woman is fallopian tubes problems with the woman is uterus andor cervix problems with ovulation uncommon problems such as the man or woman having been exposed before birth to des a medicine that was used to prevent miscarriage rates of infertility and miscarriage increase with age a woman is fertility peaks in her late 20s and gradually begins to decline in her early 30s a more pronounced drop in fertility and increase in miscarriage risk begins around her mid 30s primarily due to the aging egg supply male fertility also decreases with age but it is a more gradual decline than in women webmd medical reference from healthwise this information is not intended to replace the advice of a doctor healthwise disclaims any liability for the decisions you make based on this information © 1995 2011 healthwise incorporated healthwise healthwise for every health decision and the healthwise logo are trademarks of healthwise incorporated