Brittany Darling from Wholefood Healing Shares Why a Healthy Weight is the Key for Optimal Fertility in Men and Women.
Ensuring a healthy weight is a key factor for optimal reproductive health and fertility in both male and female partners. Infertility is defined by The World Health Organisation (WHO) as “the failure to conceive after 12 or more months of regular unprotected sex”. Approximately 10-15% of couples worldwide are considered infertile and data suggests that obesity is a material contributor to primary infertility (1). Weight management is an effective strategy for improving reproductive outcomes in couples having difficulty conceiving or maintaining pregnancy (2).
Obesity and an increased body mass index (BMI) contributes to female infertility by directly affecting the hormone regulatory axis from the hypothalamus to the pituitaryand the ovaries. Being overweight is also major component of insulin resistance, polycystic ovarian syndrome, amenorrhea (absence of periods) and anovulatory (absence of ovulation) cycles (3).
In men, increased body mass is implicated with disruption to the hypothalamic-pituitary-gonadal axis, increased adipose (fat cell) oestrogen production and reduced sperm concentration and motility (2).
Reaching an optimal weight for both partners is an effective and non-invasive way of improving fertility and pregnancy outcomes. Unfortunately, it isn’t always offered as an option. This is sometimes because of the narrow window for conception given increasing maternal age as well as concern of potential nutrient depletion if a restrictive approach is adopted prior to conception in the female (2).
Achieving an optimal weight not only increases the woman’s chance of conception both naturally and assisted, but also reduces the risk of pregnancy complications including gestational diabetes, preeclampsia, and increased infant birth weight that can lead to birth complications (1).
As well as achieving a healthy weight, ensuring both partners have sufficient levels of nutrients is a key component of fertility (4). It is estimated that 30% of women of reproductive age are iron deficient (5). Iron is an essential mineral for almost all living organisms as it participates in a wide variety of metabolic processes (6). Iron assists in the transport of oxygen throughout the body and is required for adequate neurotransmitter production, immune function and is critical for early foetal brain development in utero. Ensuring adequate iron levels prior to conception is essential for fertility, optimal pregnancy and the future health of the infant (7).
Iodine is an essential mineral for the production of thyroid hormones. During the first trimester of pregnancy, maternal thyroid activity is increased to support the development of the foetus (8). Adequate iodine stores, prior to conception can mean the mother can adequately support maternal thyroid hormones formation and the development of the unborn child for the duration of pregnancy, without her stores running low (9). Therefore having sufficient iodine levels prior to and throughout pregnancy is extremely important for the mother and infant.
The National Health and Medical Research Council recommend a total daily iodine intake of 150 mcg per day for adults and 220 mcg per day in pregnancy (8). As iodine availability in food is fairly low, compulsory fortification of commercial bread with iodised salt was introduced toAustralian in 2009, as an effective way of providing adequate iodine to the general population (10). Unfortunately, those wanting to lose weight often take the “low carb” approach and are missing out on their daily requirement of iodine.
In addition to a well balanced diet, an evidenced based prenatal vitamin is always recommended to fill any gaps in your diet.
• Afsheen Shariqu, A., Sharique, M. and Wajahat Shah, S. (2016). Insight into Female Endocrine Infertility and its Relationship to Body Mass Index. Annals Abbasi Shaheed Hospital & Karachi Medical & Dental College, [online] 21(4), pp.214-220. Available at: https://www.annals-ashkmdc.org/pdfs/2016/4/4.pdf [Accessed 24 Apr. 2019].
• Best, D., Avenell, A. and Bhattacharya, S. (2017). How effective are weight-loss interventions for improving fertility in women and men who are overweight or obese? A systematic review and meta-analysis of the evidence. Human Reproduction Update, 23(6), pp.681-705.
• Panth, N., Gavarkovs, A., Tamez, M. and Mattei, J. (2018). The Influence of Diet on Fertility and the Implications for Public Health Nutrition in the United States. Frontiers in Public Health, 6.
• Reynolds, R. and Gordon, A. (2018). Obesity, fertility and pregnancy: can we intervene to improve outcomes?. Journal of Endocrinology, pp.R47-R55.
• World Health Organisation International. (2019). WHO | Global anaemia prevalence and number of individuals affected. [online] Available at: https://www.who.int/vmnis/anaemia/prevalence/summary/anaemia_data_status_t2/en/ [Accessed 25 Apr. 2019].
• Abbaspour, N., Hurrell, R., & Kelishadi, R. (2014). Review on iron and its importance for human health. Journal of research in medical sciences : the official journal of Isfahan University of Medical Sciences, 19(2), pp.164–174.
• Schmidt, R., Tancredi, D., Krakowiak, P., Hansen, R. and Ozonoff, S. (2014). Maternal Intake of Supplemental Iron and Risk of Autism Spectrum Disorder. American Journal of Epidemiology, 180(9), pp.890-900.
• gov.au. (2019). Iodine supplementation for Pregnant and Breastfeeding Women | NHMRC. [online] Available at: https://www.nhmrc.gov.au/about-us/publications/iodine-supplementation-pregnant-and-breastfeeding-women [Accessed 25 Apr. 2019].
• Zimmermann, M. (2008). Iodine deficiency in pregnancy and the effects of maternal iodine supplementation on the offspring: a review. The American Journal of Clinical Nutrition, 89(2), pp. 668S-672S.
• Ershow, A., Skeaff, S., Merkel, J. and Pehrsson, P. (2018). Development of Databases on Iodine in Foods and Dietary Supplements. Nutrients, 10(1), p.100.