Ovarian reserve: understanding, assessing and preserving your fertility

Ovarian reserve refers to the quantity and quality of oocytes present in the ovaries. Unlike men, who produce sperm continuously, women are born with a non-renewable supply of oocytes. This naturally decreases over time, particularly from the age of 30–35 until the menopause [2], though this decline can also have other causes.

Diminished ovarian reserve is one of the leading causes of infertility in women worldwide. The ovaries of a woman with diminished ovarian reserve contain fewer eggs than usual. The remaining eggs are not necessarily of poor quality, but this condition hinders the development of the existing eggs [3]. 

A good ovarian reserve is generally associated with higher fertility, whilst a low reserve may complicate or delay conception. 

Several factors can influence ovarian reserve, starting with age, which is the primary and unavoidable factor. Genetics is also an important consideration. However, other factors can accelerate the decline of the ovarian stock, including [4]:

• A family history of early menopause or ovarian insufficiency.
• Medical treatments such as chemotherapy or radiotherapy.
• Certain autoimmune or genetic conditions.
• Endometriosis, certain pelvic infections, and ovarian surgery are all factors that can reduce ovarian reserve [5]. 
• Smoking, chronic stress, and poor lifestyle habits also have significant impacts. Inflammation in particular contributes to the decline of ovarian reserve and ovarian insufficiency [6].  

Whilst some causes are unavoidable, others can be mitigated by acting on factors such as diet.

To assess ovarian reserve, several medical tests are available. The most commonly used is the measurement of anti-Müllerian hormone (AMH). This allows an indirect estimate of the number of follicles present. A measurement oflow anti-Müllerian hormone may indicate a problem with ovarian reserve.

The Bologna criteria recommend the presence of at least two of the following three characteristics to diagnose low ovarian reserve [7]:

Advanced maternal age (≥40 years) or any other risk factor.

A previous low ovarian reserve (≤ three oocytes with a conventional stimulation protocol).

An abnormal ovarian reserve test (antral follicle count of 5–7 follicles or AMH = 0.5–1.1 ng/ml). These are the most reliable markers. 

An elevated basal follicle-stimulating hormone (FSH) level is also an indicator of ovarian reserve associated with poor response. However, a normal value without hormonal imbalance does not rule out a poor response, and the rise occurs relatively late in the progression of ovarian reserve decline. As such, it is not an ideal test for identifying this problem [8]. 

The shortening of the menstrual cycle due to early follicular development and ovulation is also an indicator of low ovarian reserve [9]. 

These tests should nonetheless be interpreted by a doctor. The healthcare professional can then prescribe an appropriate treatment.

A low ovarian reserve does not always mean infertility, but it can reduce the chances of conception, particularly naturally. For some women, this means turning to assisted reproductive technology (assisted reproductive technology (ART) journey), including in vitro fertilisation (IVF).

A good understanding of ovarian reserve therefore allows important decisions to be anticipated, such as egg freezing or pursuing a specific treatment. 

Acting on diet and stress

There is no miracle solution for increasing ovarian reserve, but certain steps can help to preserve it:

• Adopting a balanced diet rich in antioxidants.
• Avoiding tobacco, alcohol and limiting exposure to endocrine disruptors.
• Managing stress, which can influence the menstrual cycle and ovarian function.
• Considering oocyte vitrification at a younger age if motherhood is planned for later.

For example, the Mediterranean diet (rich in nuts, vegetable oils, vegetables, fruit, fish and legumes, with few dairy products) is beneficial[10]. By contrast, when considering the "Western diet", data suggest that a diet high in fat is associated with negative influences on oocyte maturation and follicle development[11]. Diet is often the first treatment to focus on. 

Good overall nutritional status will also have an impact. Vitamin B9, for example, is essential[12].

A pregnancy food supplement multivitamins can be worthwhile from the moment you start trying for a baby, to give yourself the best possible chance.  

Boosting egg quality

Oocyte quality refers to the ability of the oocyte to complete meiotic maturation (including correct chromosome segregation) as well as to support fertilisation and embryonic development, ultimately resulting in a successful live birth[13].

A few conditions that can have a particular impact on this point: gynaecological conditions such as endometriosis and PCOS, oxidative stress, and lifestyle factors (diet, stress, sleep, etc.). 

Certain actives can thus help to boost the oocyte. These ingredients in particular address how to improve egg quality : 

• Coenzyme Q10. Studies show that it can significantly reduce oxidative stress, increase fertilisation rates and improve embryo quality[14].
• N-Acetyl-cysteine (NAC). It helps to increase glutathione levels[15]. Research has shown that oocytes with higher levels of intracellular glutathione produce healthier and stronger embryos. The protective action of FSH on embryonic development is largely due to glutathione synthesis[16].
• Tryptophan[17]. It helps to increase melatonin levels, which is beneficial for oocyte maturation. A study shows it helps to increase the number of mature oocytes as well as pregnancy rates.
• Zinc[18]. It plays a key role in follicle development and oocyte maturation.
• Myo-inositol[19]. It improves oocyte and embryo quality, and also contributes to increasing pregnancy rates.

Taking a food supplement to get pregnant containing these actives can therefore give a helpful boost. Our supplement Ovo+ contains Coenzyme Q10, NAC, tryptophan and zinc. 

Ovarian reserve is an essential marker of female fertility. While it naturally declines over time, other factors can also compromise it. With the right tests, it is possible to assess your situation. A low ovarian reserve does not necessarily mean assisted reproduction with IVF. Good overall lifestyle habits, appropriate medical follow-up and, where necessary, preservation options can help. Suitable treatments or supplementation may also help.