Women are becoming mothers later and later. The average age at which a woman in our country has her first child is 29.3 years. In 2000 it was still 27 years. Medically, that shift isn’t great news, but parenting later in life also has benefits. After all, those who are older are more stable in life, and often the partner relationship is also stronger.
Usually, a pregnancy after the age of 35 is considered a ‘geriatric pregnancy’. A very confrontational and unflattering term, but therefore not unjustified. Because the older you get, the less likely you are to get pregnant naturally. Women between the ages of 25 and 30 have a 20 percent chance of getting pregnant each month. Are you between 30 and 35? Then that’s only 10 percent. If you are approaching the age of 38, you still have a 5 percent chance of getting pregnant each month.
“This reduced fertility is linked to the quantity and quality of your eggs,” says Dr. Lisbeth Jochems, gynecologist at the Antwerp University Hospital (UZA). “Every girl has approximately one million eggs stored in her ovaries at birth. New eggs are never created, on the contrary. The older you get, the more eggs disappear. When a girl has her first period, an average of 300,000 to 500,000 eggs remain. At the start of each menstrual cycle, a group of eggs is always ready. One of those cells continues to mature and separates from the ovary (ovulation). Those other cells are destroyed by your body.”
The older you get, the smaller the stock. Around the age of 50, the start of menopause, all the eggs are gone and you can no longer get pregnant naturally. But because the quality of the eggs is systematically decreasing, fertility has already fallen sharply in the years before menopause. “Your eggs are just as old as you. The longer they are in your body, the more likely that the DNA of those cells will be damaged,” explains Dr. Jochems out. “These older eggs are also less easy to fertilize and do not settle as well in the uterus. The older the egg, the greater the chance of chromosomal abnormalities in the baby, such as Down’s syndrome.”
After 35 years we therefore speak of a high-risk pregnancy. “But let me reassure you: that does not mean that your life or your child’s life is in danger. You only run a higher risk of complications, such as gestational diabetes, high blood pressure or preeclampsia. In addition, if you are older than 45, you have a 75 percent chance of a miscarriage. Premature birth is also a significant risk.”
Your eggs are the same age as you. The longer they are in your body, the greater the chance that the DNA of those cells will be damaged.
Sperm also ages
And then there are the pregnancies that get a boost from science. Think of in vitro fertilization or egg donation. “We can apply in vitro fertilization to women up to the age of 43, but age also has a clear impact here,” says Dr. Anne Delbaere, head of the gynecology department at the University Hospital of Brussels (H.U.B). “If you are younger than 36 years old, you have a 30 percent chance of having a child. Between the ages of 36 and 40, that percentage drops to 15 percent. Between 40 and 43 you still have 6 percent. Women here also underestimate the impact of age on fertility. Nor do men escape the test of time. “Sperm from older men is also more likely to have DNA abnormalities. Often it is a combination of factors: older women who have a child with an older man. Then you pile up the risks.”
But of course there are also advantages to a pregnancy at a later age. A couple often has a lasting relationship because they have already been through a few things together. Mothers-to-be usually have a higher education. They have a larger financial reserve and a stable job. Moreover, they have already seen many examples of family formation and upbringing with friends and relatives, which gives them a good idea of how they want to approach parenthood.
“The socio-economic context certainly has an impact,” says Dr. Delbaere. “In the 1980s, women had their first child at the age of 25. That age has moved up for positive reasons: education of women, integration in the work field and access to contraception. That is certainly a positive development, but women are still insufficiently informed about the way their fertility is evolving. If you are sure of your desire to have children, it is best not to wait too long. Or have your eggs frozen, preferably before the age of 30.”
Can we control time or is that just an illusion? Unless someone discovers the secret to eternal life, everyone remains subject to a certain timeline that no reproductive technology can match. For example, an older mother is less likely to see her grandchildren grow up. On the other hand, a late desire to have children is a nice metaphor: women can do anything, even if they are over 40. Starting a business, running a marathon, having a child… Becoming a mother at a later age undoubtedly confronts you with your own mortality, but also points you to all the possibilities that life has in store.