Approximately 10 percent of couples in the United States suffer from infertility, according to the University of Maryland Medical Center. Infertility causes are fairly evenly divided between male and female issues, with around 20 percent of couples each having problems that contribute to infertility, gynecologist Tommaso Falcone, M.D. of the Cleveland Clinic reports. While in some cases infertility occurs from structural problems such as blocked fallopian tubes, which can't be helped by nutrition, nutritional factors do play a part in some types of infertility.
Overweight
Being overweight is a known fertility risk factor for both men and women. Women who are 5 to 10 percent overweight may have problems with ovulation and may not have regular periods. Women with polycystic ovary syndrome are often, but not always overweight. Women with PCOS have abnormal insulin responses and an imbalance in estrogen, the dominant female hormone, and male hormones, called androgens; around 33 percent of women with PCOS have fertility issues, according to Dr. Falcone. Overweight men may have erectile dysfunction as well as low testosterone levels, which affect sperm production.
Underweight
Women who are underweight often stop ovulating, since the body needs a certain percentage of fat to manufacture female hormones necessary for reproduction. Women who are 10 to 15 percent underweight may stop ovulating and may not have normal periods. Women who exercise strenuously may also stop ovulating.
High Blood Sugar
Male diabetics whose blood sugar levels are high enough to require insulin treatment have sperm that may look normal, but that have abnormal DNA, researchers from Queens University in Ireland reported at the 2008 European Society of Human Reproduction and Embryology Conference. Diabetes in men can also cause nerve damage that leads to impotence and retrograde ejaculation, where sperm enter the bladder rather than being ejaculated through the penis.
Vitamin D Deficiency
Vitamin deficiencies may contribute to infertility in some cases. Vitamin D and calcium supplements may help women with PCOS achieve normal periods, according to several studies. A study conducted by researchers from Columbia University and reported in the June 1999 issue of "Steroids" gave 13 women with PCOS vitamin D and calcium supplements. Within two months, seven experienced normalization of their menstrual cycles and two became pregnant. A Greek study reported by researchers from the AHEPA University Hospital in the September 2009 issue of "Fertility and Sterility" gave vitamin D3 supplements to 15 obese women with PCOS. Over three months, cholesterol levels improved and insulin resistance decreased. Researchers concluded that vitamin D therapy could help manage PCOS, which could be a factor in as many as 20 percent of infertility cases, according to Dr. Falcone.
References
- University of Maryland Medical Center: Infertility in women - Risk Factors
- ScienceDaily: Diabetes Linked To Male Infertility; Excess Sugars In The Body Have Direct Effect On Sperm Quality
- Diabetic Care Services: Common Diabetes Complications: Diabetes & Infertility
- PubMed.gov: Vitamin D and calcium dysregulation in the polycystic ovarian syndrome
- PubMed.gov: Role of vitamin D treatment in glucose metabolism in polycystic ovary syndrome
- PubMed.gov: Obesity and infertility
