Nutrition has a significant impact on fertility. To get pregnant, a couple needs a healthy egg to join to healthy sperm, which is then implanted inside the woman’s uterus. Nutrition can impact the health of the egg, the health of the sperm, the production of fertility hormones which impact the timing of ovulation, the health of the uterus (and consequently the likelihood of implantation), and the growth and development of the fetus.
There are 4 key stages of support that nutrition intervention is required.
Trying to conceive
The first stage is couples who have just started trying to conceive. The key message for these clients is the impact of nutrition to shape their baby’s future. Research suggests that preconception nutrition can influence genetic programming to impact a child’s future weight, risk of chronic diseases and cognitive abilities[i],[ii]. For example, a study by Dr Petry and colleagues suggests that pre-conception maternal and paternal lipid intake may impact genetic printing to influence the child’s future development and metabolism[iii]. Furthermore, a Mediterranean-style diet and monounsaturated fat intake during pregnancy has been linked to decreased cardiovascular disease risk for the baby later on in life[iv],[v].
Stage two is clients with pre-existing or newly diagnosed dietary conditions which increase the risk of infertility. Conditions include Poly Cystic Ovarian Syndrome, Endometriosis, Insulin Resistance, Inflammatory Bowel Disease, Thyroid conditions and more. Couples with dietary conditions need to be counselled that optimal dietary management may assist in improving fertility outcomes. For example, studies suggest that endometriosis may be improved with an anti-inflammatory type diet[vi]. EVOO has been found to be beneficial for immune-inflammatory diseases such as Rheumatoid Arthritis and Inflammatory Bowel Disease, and may also play a protective role in endometriosis[vii]. Current studies suggest that a Mediterranean-diet style may be beneficial for clients with Poly Cystic Ovarian Syndrome[viii].
Assisted reproductive treatments
The third stage of couples requiring nutrition intervention are those undergoing Assisted Reproductive Treatments (ART). ART includes a range of procedures such as ovulation induction for women who aren’t ovulating regularly, and artificial insemination, where semen is transferred directly into a woman’s uterus. Before moving onto In Vitro Fertilisation, solving problems utilising diet and lifestyle should be considered. For example, around 30% of fertility problems arise from male sperm health[ix]. Studies suggest that olive oil and EVOO may help to improve semen quality and sperm functionality which may improve ART outcomes[x],[xi].
Secondly, optimal egg health is essential for successful ART. Inflammation in the fluid surrounding the egg impacts egg quality and decreases the chance of conception[xii]. Studies show that EVOO helps to minimise inflammation[xiii].
Thirdly, approximately half of all embryo implantations result in failed pregnancy[xiv]. Although this can be caused by the health of the embryo, uterine receptivity is also an important factor. Women require a thick uterine lining of at least 7milimeters for implantation. Studies suggest that vitamin E supplements may help to increase the thickness of the uterine lining, although the mechanism for this remains unknown. EVOO is a rich dietary source of vitamin E, and although no studies have been conducted, it is plausible that the vitamin E in EVOO may be one of the factors contributing to it’s benefit in women who are trying to conceive. Furthermore, aspirin is often given to reduce inflammation. Studies show that EVOO has significant anti-inflammatory effects[xv].
In Vitro Fertilisation
The final stage of nutrition intervention is for couples undergoing In Vitro Fertilisation (IVF). IVF literally means ‘fertilisation in a test tube’. The embryo is then transferred into the woman’s uterus. Studies suggest that adherence to a Mediterranean-style diet, including the use of EVOO may strengthen IVF outcomes. For example a study by Dr Vujkovic and colleagues found that women consuming a more Mediterranean-style diet were more likely to become pregnant through IVF than those consuming a more ‘health conscious’ dietary style which was lower in healthy oils and legumes[xvi]. These results were substantiated by Dr Karayiannis and colleagues who found that a 5 point increase in the Mediterranean Diet Score resulted in a 2.7 times higher likelihood of pregnancy through IVF[xvii].
Furthermore, a diet high in olive oil and fish, and low in meat, was found to improve embryonic growth and minimise risk of miscarriages[xviii].
In summary, current research suggests that extra virgin olive oil may be beneficial for fertility whether couples are trying to conceive naturally, have dietary conditions which may impact their fertility, are undergoing Assisted Reproductive Treatments or In Vitro Fertilisation.
View article references
- https://www.n cbi.nlm.nih.gov/pubmed/27794174