Odds of Getting Pregnant by Age

Though the biological clock scientifically refers to the circadian rhythms that govern the sleep-wake cycles, it’s mainly associated with a woman’s fertility and her decreasing chances of getting pregnant with age. 

However, over the years, statistics have shown that more people are delaying having children until their late 30s or 40s for many different reasons. But for many women and men, the older you grow the as you age, and so does your reproductive system. Thanks to advances in reproductive technology, couples still can start a family even in later years.

• Age is one of the largest factors affecting people’s ability to conceive, especially so for those assigned female at birth.
• AFAB individuals begin to see a gradual decline in fertility in their early 30s, with a more pronounced drop-off starting shortly before turning 40.
• Individuals assigned male at birth can potentially remain fertile for their entire adult lives. However, an increase in erectile dysfunction is seen around age 40, and a decrease in sperm quality around the same time can have negative health outcomes for offspring.
  
  

Female Fertility

A woman is born with approximately 1–2 million eggs in her ovaries. However, this number is higher when in fetal development as they are born with around 6 million eggs, or oocytes. By the time a female gets to puberty, the total number of egg reserves drops to around 300,000.

A woman releases at least 1 egg during her menstrual cycle. As a woman ages, they may need to rely on assisted reproductive technologies to help them conceive. On the other hand, those trying to conceive naturally must understand the timeframe they are working with to increase their chances of conception. 

According to the NIH, fertility technically declines throughout the entire early adulthood of females born with a uterus, but a significant decline begins in the late 30s. Between the ages of 35 and 40, the likelihood of conceiving naturally drops by nearly 25 percent.

Fertility in the 20s

Women are most fertile in their late teens to early 20s. During this period, there is around a 25% chance of a pregnancy occurring during each monthly menstrual cycle. Studies show that women in their 20s have a 25% higher chance of conception within one menstrual cycle. Studies have shown that women in their 20s have a 71% chance of getting pregnant within a year of trying. Not only that, but they also have a reduced chance of miscarriage because 90% of their eggs have normal chromosomes. As they enter their mid to late 20s, women of this age are still fertile and chances of getting pregnant are still high. As long as sexual activities are timed with ovulation, pregnancy can be instant (unless there are underlying issues). Actually, women in this age bracket can get pregnant within a year and their chances of a miscarriage are also low. 

Fertility in the 30s

As a woman enters her 30s, the likelihood of a successful conception starts to drop and the chances of a miscarriage begin to rise. But, many women still get to conceive without the help of assisted reproductive technology. Help is offered when one has been trying to conceive unsuccessfully for a year. Moving towards their mid to late 30s,  fertility begins to decline, especially due to reduced egg quality as they tend to have more chromosomal defects. A woman’s chances of getting pregnant are reduced and naturally now stand at 15% in each cycle. The chances of conceiving naturally within a year have also reduced standing at 67%. 

Fertility in the 40s

This is where fertility begins to decline rapidly. At this age bracket, 90% of the eggs produced have chromosomal abnormalities, and the uterine lining begins to thin. Moreover, the blood supply to the uterus decreases, making it harder for implantation to happen. Women attempting to get pregnant at age 40 still have a 56% chance of becoming pregnant within a year, but this percentage continues to fall as each year passes by. The risk of miscarriage also begins to rise and studies have shown that 27% of pregnancies in 40-year-olds do end in miscarriage, compared to a 16 percent miscarriage rate in individuals aged 30 or lower.

Though some women do conceive naturally and successfully carry a pregnancy to term, most women need help from assisted reproductive technology. Ivy Fertility offers women or couples struggling with fertility different options and the compassionate healthcare providers walk with you during your fertility journey. Before women approach menopause, there’s a previous stage known as perimenopause that can last up to 10 years. In this stage, your cycle becomes shorter or irregular. If you’re planning to conceive, you have to time sex with ovulation. 

Male Fertility

Men differ from women when it comes to fertility. For starters, unlike women, who are born with all their eggs, men only start to make sperm once they hit puberty. Nonetheless, male fertility is also affected by age and can decline once a man hits 40. Peak fertility typically occurs sometime between 25 and 29, with sperm quality beginning to decline around age 30. A 2022 study found that there is a significant increase in the likelihood of erectile dysfunction in individuals over the age of 40. 

Additionally, other fertility problems in men include:

• Low sperm count
• Low motility
• Sperm morphology (sperm with an unusual shape that makes it harder for them to move or get inside the egg).

Still, many assigned at-birth males remain fertile to some degree throughout their entire adult lives. While they continue to produce sperm later in life, the quality of this sperm declines with age.

The Bottom Line

When women are born, they already have all the eggs (around 1 to 2 million eggs) they will need.  As one grows older, the number of eggs continues to reduce. This means that the longer one waits to have a child the harder it can be. Nevertheless, this isn’t the case for everyone and some older women have conceived naturally. Thanks to assisted reproductive technologies like IVF, women who choose to wait until they're older can have a chance to start a family. Consulting your doctor will let you know if there’s cause to worry.