CNN reports that “women over 35 struggle the most to get pregnant. As a woman ages, the quality of her eggs tends to decline and she may not ovulate as frequently.”

Obstetrician and gynecologist Michael Randell says that a woman has only a 15 percent chance of conceiving each month. About 85 percent of people will conceive in the first year of trying. It may seem that people are having more problems getting pregnant these days, but this is because more people are waiting longer, according to Randell.

He also blames monthly timing. “It’s one of the most shocking things that I see, when patients really don’t know that they only have a small window of opportunity to get pregnant each month. The optimal time of the month for ovulation is 14 days after the first day of your last menstrual period.”

Nevertheless, many couples are putting off starting a family becuase they want to spend time together without the complication of children. Just remember, if you delay, there may be a price to pay later on.