The lowdown on fertility after 35

As a 30-something year old childless woman, a quick Google search on this very topic can seem both overwhelming and scary if you’re trying to conceive naturally over the age of 35.

Over the last decade, there’s been a big shift in the number of women deciding not to have children or waiting till later in life to conceive.  In fact, the average age of a woman having her first child in the UK is 30.7 years old and over 50% of women aged 30 are childless.  

So, if you do plan on having kids, (or if you haven’t made your mind up yet) it’s important to equip yourself with the right knowledge about your fertility and to understand what happens in your glorious third decade of life.

So, what’s the biology?

Girls are born with a fixed number of eggs in their ovaries. Most girls are born with about 2 million eggs. In adolescence that number reduces to 400,000 and by the age of 37 that reduces again to 25,000. A woman’s peak reproductive years occur in her late teens and early 20’s. As you age, not only does the number of eggs decrease but so does the quality of these eggs. Both the number and the quality of these eggs determine your fertility.  

By age 30, a woman’s fertility starts to decline. This decline happens faster once you reach your mid-30’s. And by 45, it is deemed unlikely that a woman will be able to fall pregnant naturally – but not impossible.

Female fertility after the age of 35

The greatest reduction in fertility happens between the ages of 35 and 40. However, if you’re reading this in your late 30’s and starting to panic – please don’t. 1 in 5 women will go on to have healthy babies after the age of 35.

It’s also important to understand that a woman’s fertility is multifactorial, and every woman is different. Ageing is probably the biggest factor of determining fertility, however there are also several genetic and lifestyle factors that may influence how quickly a woman’s egg reserves decline.  

These include:

  • Certain medical and hormonal conditions including endometriosis, polycystic ovarian syndrome (PCOS) and thyroid problems.  
  • Smoking is toxic to eggs and may cause premature damage.  
  • Obesity as excess weight may induce an inflammatory reaction that affects egg quality and implantation.
  • Certain sexually transmitted infections can cause blocked fallopian tubes, increasing the risk of infertility.

Risks of conceiving after the age of 35

Getting pregnant after the age of 35 also carries risk of complications during pregnancy.

Some of these include:

  • Increased likelihood of having a baby with down syndrome  
  • Increased chance of miscarriage
  • Increased risk of pregnancy complications such as gestational diabetes, ectopic pregnancy, and placenta problems  
  • High blood pressure  

Male fertility over the age of 35

Like females, male fertility will also start to decline after the age of 35. The quality of a man’s sperm can start to decline, making it more difficult to fertilise the egg.  

According to the National Institute of Health, one third of all fertility challenges are due to male infertility. There are several causes of male infertility including sperm disorders, retrograde ejaculation and hormonal issues which can lead to poor growth of sperm.  

What steps can I take to give myself the best chance?

Despite the risk factors, many women around the world give birth to healthy babies after the age of 35. It’s important to understand your own body and reproductive cycles first and foremost. If you plan to try for a baby, tracking your ovulation is an excellent way to ensure that you’re giving yourself the best chance to fall pregnant naturally. You can also implement changes in your lifestyle including regular exercise and healthy eating, stop smoking, reducing your alcohol intake and taking folic acid.  

There are also different ways to check your fertility through blood tests which can be done by a medical professional or completed with at-home testing kits.  

Medical professionals will recommend trying to conceive naturally for at least 12 months before considering other routes such as IVF. We recommend you consult your doctor or medical professional if you think you are experiencing fertility issues.  

For more information and support, see below:

Pregnancy birth and Baby
British Fertility Society
NHS – Infertility
Baby Center – Getting pregnant in your 30’s

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