An irregular menstrual cycle is probably the most common sign of infertility a woman may notice. However, irregularities in the period are not necessarily an indication that there is an infertility problem - there may be other conditions that need taking care of.
Women who are underweight or overweight (obese) may experience infertility problems. If someone is too thin, they will be lacking the necessary nutrients to successfully conceive and then carry the baby to full term. Likewise, overweight women often suffer with hormonal problems and this can lead to their reproductive systems being adversely affected.
Alcohol and drug misuse can also leave a woman childless but these tend to be causes as opposed to signs of infertility. Those who abuse their bodies in this way incur all kinds of damage which affects the way things work within and when proper conception and growth of the fetus is discouraged they set themselves up to be likely candidates for childlessness.
Anatomic or physical problems in connection with testicles which have not dropped as they should have may signify infertility in the male of the partnership. Men who wear tight underwear and bottom half clothing may also be unable to produce sperm suitable for conceiving a baby. This area of their manhood should not be exposed to heat as this can also have an effect on reproduction.
When a couple have been trying to have a baby (taking part in unprotected sex on a regular basis) for between one and two years it is time to seek the advice of the medical professionals.