Ovarian Reserve Tests
An ovarian reserve test looks into how well your ovaries are functioning. It is one of the common female fertility tests that forms part of a Fertility MOT at our London IVF clinic.
It is well known that a woman’s ovarian reserve reduces with age. Nowadays, the majority of women would start a family in their thirties. It is therefore helpful to know more about your ovarian reserve and the implications on your chances of getting pregnant or whether you can safely delay for another couple of years.
What is an ovarian reserve?
Women are born with around 4-5 million eggs. These remain dormant or in a quiet state until puberty. During this period, there is a slow but steady loss of the follicles and only 400,000 – 500,000 follicles remain by puberty. This gathers pace around the age of 35 years and decreases rapidly in 40s.
What causes a low or reduced ovarian reserve?
A low or reduced ovarian reserve is caused by a range of factors. Age is one of the most common factors that causes low or reduced ovarian reserves. Ever since birth, there is a decrease in the quality and quantity of eggs that carries on at a slower pace. But, it gathers pace over the age of thirty-five and there is rapid decline past the age of forty. The reduction in egg quality and quantity is a natural aging phenomenon. Hence, it may take longer for women to conceive at later ages. Occasionally, it may result in failure to conceive either naturally or following fertility treatments such as IVF or artificial insemination.
Besides age, there are certain illnesses that may lead to low ovarian reserve. Such as endometriosis, pelvic infection, pelvic surgery, tubo-ovarian surgery, removal of ovary or past history of treated cancer, autoimmune causes, family history of premature menopause or infertility, carrier of Fragile X mutation, smoking, etc. In some women there might be no obvious identifiable reason.
How can I check my ovarian reserves? What fertility tests form part of ovarian reserve test?
Ovarian reserves are checked as part of the female fertility MOT. It is assessed by a combination of parameters. The best marker for the quality of the eggs is a woman’s age. As one of the best London IVF clinics, we use a combination of blood tests and trans vaginal pelvic ultrasound scans when checking ovarian reserves. Some of the tests that form part of the ovarian reserve assesment are Anti-Mullerian hormone or AMH, Follicle Stimulating Hormone or FSH, Inhibin B, clomiphene citrate challenge test (CCCT) and Antral Follicle Count or AFC. None of these tests on their own provide a reliable answer. Hence, at London IVF and Genetics clinic, as part of the female fertility MOT we use a combination of female fertility tests such as Anti-Mullerian hormone or AMH, Follicle Stimulating Hormone or FSH and antral follicle count or AFC to gain comprehensive information about your ovarian reserves.
What is anti-mullerian hormone or AMH?
Anti-mullerian hormone or AMH is a hormone that is produced by cells surrounding the dormant primordial follicles. The AMH can be tested any time in the menstrual cycle. A lower value of AMH indicates low, reduced or diminished ovarian reserves. The lower the AMH value, the lower the ovarian reserve and the lower the chance of getting pregnant when trying naturally or following fertility treatment such as IVF or artificial insemination or IUI.
What is Follicle stimulating hormone or FSH?
Follicle stimulating hormone or FSH is a hormone produced by a small gland in the brain called the pituitary gland. FSH regulates the function of the ovaries. FSH is measured by taking blood tests; ideally between days 2–4 of the menstrual cycle. The high FSH level indicates low or reduced ovarian reserves. Like AMH, this would imply reduction in the ovarian reserve and therefore lead to a delay when trying to conceive or a reduced success rate following fertility treatment such as IVF, artificial insemination or IUI.
What is Inhibin B?
Inhibin B is a hormone produced by the cells surrounding these dormant primordial follicles. The levels may fluctuate and as such this is usually not recommended as a reliable marker for assessing ovarian reserve.
What is antral follicle count or AFC?
Antral Follicle count or AFC is the number of small follicles in both the ovaries. It is measured during a trans vaginal pelvic ultrasound scan. These are the follicles that develop in a natural cycle and result in ovulation. This helps in understanding the response to fertility drugs when going through fertility treatments like IVF or artificial insemination or IUI.
There is no single test that, in isolation, can give a 100% accurate answer, and therefore, specialists usually use a combination of tests to improve the predictive power and reliability of the assessment.
How does ovarian reserve affect female fertility?
Low or reduced ovarian reserves do affect female fertility both when trying to conceive naturally or following IVF. Low AMH or antimullerian hormone or high FSH means that for some reason ovaries are aging faster. It may affect both the quality and quantity of eggs. The poor quality of eggs may also affect the embryo quality. This may result in a delay in conceiving or early pregnancy miscarriage or failed fertility treatment.
What if I have low ovarian reserve or low AMH (low anti-mullerian hormone) or high FSH?
It is important to stress that low ovarian reserve does not necessarily mean that you can never get pregnant. For some women it may mean that it will take longer when trying to get pregnant. If you have been trying unsuccessfully for some time, then you should see a fertility specialist for further advice. For others, who are going through fertility treatments such as IVF, they may experience lower IVF success rates. A small proportion of women with very low ovarian reserves may have to consider using donor eggs for their treatment to help them get pregnant. Hence, the window of opportunity for trying naturally or with treatment is shorter and women with diminished reserves should seek early advice and help.
Am I going through menopause if I have low AMH or high FSH or a low ovarian reserve?
No, low ovarian reserve does not imply that you are going through menopause or are peri menopausal. It simply indicates your fertility potential. Women with a reduced ovarian reserve usually have a regular cycle, but have a lower chance of getting pregnant per menstrual cycle (also known as fecundity). However, if you do experience absence of menstrual cycles or erratic cycles, then you should consider seeing your Doctor or Gynaecologist.
To find out more about a female fertility MOT at London IVF & Genetics Centre click here.
