Have you heard the term ovarian reserve? Healthista Editor Olivia Hartland-Robbins looks into what ovarian reserve means and what getting it tested can tell you about conception and fertility
Wouldn’t it be great for women to predict their chances of pregnancy before they start trying?
Getting pregnant should be an easy and natural process, but for many this isn’t the case. In fact, around one in seven couples in the UK may have difficulty conceiving.
Fertility difficulties can arise due to factors such as health, fitness, lifestyle habits, genetics and age.
one in seven couples in the UK may have difficulty conceiving
Thankfully, changes to habits, diet and exercise can be made to encourage chances of conception and increase fertility. However, when it comes to age, we can’t turn back time.
Age is a key factor when it comes to fertility in women, and this is largely due to something known as ovarian reserve.
What is ovarian reserve?
‘Ovarian reserve’ refers to the number of eggs (also known as oocytes), a woman has remaining in her ovaries.
Women are born with their lifetime supply of eggs – around two to four million. As women age, their ovarian reserve decreases.
At the start of puberty women will have around 400,000 eggs. By the time a woman reaches her late 30’s this number falls to around 27,000 .
As women age, their ovarian reserve decreases
Eggs will continue to be lost until a woman reaches the menopause. In the UK, the average age for a woman to reach menopause is 51, according to the NHS. At the start of the menopause women will have around 1,000 eggs left.
Diminished ovarian reserve (DOR) is the term used for when women lose their reproductive potential – the less eggs a woman has, the harder it is to fall pregnant.
Ageing and the menopause are the main cause of DOR.
Other causes include :
- Cigarette smoking
- Alcohol consumption
- Genetic abnormalities
- Aggressive medical treatments (such as chemotherapy or radiation for cancer)
- Ovarian surgery
Ovarian reserve testing – who is it for?
If fertility potential largely depends on age and ovarian reserve, how can women ensure they have an adequate supply of eggs to start a family when the time is right?
An ovarian reserve test reveals the potential number of eggs a woman has left in her ovaries. This indicates how much time a woman has left to conceive and when she is likely to start the menopause.
It is a good idea to have an ovarian reserve test if you have been struggling to conceive or if you are planning on starting a family later in life.
reveals the potential number of eggs a woman has left in her ovaries
The American College of Obstetricians and Gynaecologists recommends the test for women older than 35, who have not conceived after six months of attempting pregnancy, or who have received chemotherapy or radiotherapy or had ovarian surgery for endometriosis.
A test provides women with options if their ovarian reserve turns out to be lower than usual. Whether that be choosing to freeze their eggs for later pregnancy or opting for fertility treatments, should they need to.
What does a test involve?
During every menstrual cycle, several eggs grow and collect fluid around them in pouches called antral follicles, in preparation for ovulation and fertilisation.
The more antral follicles a woman has, the more eggs she will have, making pregnancy more likely.
The average 25 to 34-year-old should have an ovarian reserve of around 15 to 30 antral follicles, fewer than ten at this age is considered low.
Tests to measure antral follicle amount include:
– Anti-Müllerian hormone (AMH) or follicle-stimulating hormone (FSH) blood test. These hormones play a key role in the development of ovarian antral follicles.
– Antral follicle count (AFC) vaginal ultrasound, whereby the follicles are counted to estimate ovarian reserve (egg supply).
The simplest test is the AMH blood test, where the level of AMH found in the blood can help estimate the number of ovarian antral follicles.
If the level of the AMH hormone is normal, this indicates a good ovarian reserve and antral follicles, which means further years of reproductive capability ahead.
a test can be organised privately through gynaecologists and most fertility clinics
This non-invasive AMH test is not yet available via the NHS. However, a test can be organised privately through gynaecologists and most fertility clinics.
The cost of an AMH test is around £120 to £130, such as this one from LetsGetChecked.
While AMH tests provide you with an idea as to how many eggs you have in reserve, they won’t flag up any other issues you may experience when it comes to conception.
If you are struggling to get pregnant, you should first contact your GP, who will look into your medical history and give you a physical examination.
Your GP may also refer you to a fertility specialist at an NHS hospital or fertility clinic.