Debunking myths about the effect of age on fertility

Most people believe that a woman is most fertile in her early twenties. Once a woman hits 25 years, people start to ask questions about her settling down and having babies because they think she’s at her ‘peak period’ and she might ‘run out of eggs’ soon. Relatives and friends start the match-making process and a happy healthy woman starts to think that maybe, just maybe, they are right.

Have you ever stopped to think that these theories on the impact of age on fertility might not be entirely accurate? What if most of these theories are not true about all women?

A psychologist at the San Diego University in the U.S., Jean Twenge, said when she was ready to start a family, her doctor told her about how the odds of women over 35 years conceiving were not very high. She was 34 years old and had just got married when she heard this. “That was very frightening to me, as it is to many women, who are in their 30s,” she said.

Her anxiety drove her to research on the theory and she discovered that it had come from statistics carried out in France, in the 1700s.

“They put together all these church birth records and then came up with these statistics about how likely it was [someone would] get pregnant after certain ages.

“I can empathise slightly with the researchers in this area. It is difficult to draw conclusions about age and fertility from modern populations where birth control is widely used,” she said.

More current studies have shown that in recent times, more women in their mid- and late 30s conceived within a year of trying.

One of the most popular studies is that of David Dunson, a professor in Duke University, USA. He discovered that 82 percent of women between the ages of 35 and 39 got pregnant within a year.

He also discovered that although fertility declined with age, it was not as early as many women had been led to believe.

Dunson’s study showed that 86 percent of women from 27 to 34 years would have conceived within 12 months of trying. So the results were only 4 percent lower than that of the women from 35 to 39 years.

Many studies have shown that children conceived in advanced years are more likely to have certain chromosomal abnormalities than those born to younger women. Some researchers believe that these risks have been exaggerated over the years.

David James, a product development manager at the UK National Institute for Health and Care Excellence, said that the chance of chromosomal abnormality in 20-year-old women is one in 500 and in 30-year-old women, one in 400. The number goes to one in 60 to 70 women at 40 years.

“Turning that on its head, it does mean that 59 out of 60 women aged 40 will have no chromosomal problems in their baby at all,” James says.

These studies have shown that while it might be harder for women to get pregnant in advanced years and the risks of having chromosomally abnormal children increases, the difference is not as bad as popular theories have caused many to believe. Such issues are usually more common in women, who try to conceive through artificial insemination and In vitro fertilisation (IVF).

“Those statistics are more discouraging for older women. The difference in success rates in IVF between your early 30s and your late 30s is a lot bigger than the difference in success in natural conception,” Twenge further explains.

Recent studies have shown that popular fertility problems in women over 30 years may not be as a result of advancing years. If many of them had tried to conceive in their 20s, they would have experienced similar difficulty.

According to Lord Winston, a fertility expert, “Doctors who give blanket advice to populations… are making all sorts of presumption. We eventually find out that so much of this advice is spurious and unnecessary and often wrong.”

In Nigeria, and many other countries in the world, the use of contraceptives has been discovered to be another factor that affects the ease of conception. Studies have shown that the use of some contraceptives, like the morning-after pill, will negatively affect the fertility of teenage girls when they are ready to have children later in life.

Naturally, and without any circumstances that might affect the fertility, both medical and otherwise, middle-aged women can conceive, carry their pregnancies for full term and deliver healthy babies. The general assumption and theories that state otherwise, while carrying some truth in regards to certain people, are not 100 percent true for all women.