Age and Ovarian Reserve — Egg Quantity and Quality

Your age is one of the most important factors in the ability to get pregnant because it affects the number of eggs you have left and the quality of those eggs. Together, egg quality and quantity are known as your ovarian reserve.

In general, the quality and quantity of your eggs is highest up until your early 30s. This is the time period when you are most fertile. After your early 30s the quality and quantity begin to decline, and your fertility does as well. There are significant declines in fertility occur in the mid 30s and early 40s. This is because there are fewer eggs overall, and the eggs are more likely to be poor quality than good quality.

Egg Quantity

The concept of egg quantity is pretty straightforward: You are born with a certain number of eggs in your ovaries, and as you get older this number becomes smaller and smaller. Some women are just born with fewer eggs, too, so a younger woman could also have low egg quantity.

The fewer eggs you have, the harder it is for your hormones to recruit and develop an egg, no matter how hard your body tries. Without ovulation, it is impossible to get pregnant, and it can be very difficult to get pregnant with irregular ovulation.

Egg Quality

Many women who have regular periods simply assume that their eggs are fine.But even if you are ovulating regularly, it does not mean that the eggs are of sufficient quality to result in a pregnancy.

If a poor quality egg is fertilized, one of two things usually happens. One is that the egg might be unable to implant. The other is that the egg might be able to implant, but then be unable to develop properly. This would result in a miscarriage.

Though older women are more likely to have poor quality eggs, younger women can have poor quality eggs, too. Smoking, radiation and chemotherapy can all reduce the quality of eggs. Endometriosis can also result in poorer quality eggs. Sometimes it is simply genetic.