The effects of lifestyle on fertility
Our natural fertility is influenced by many factors, some of which are determined by genetics, while others may be related to the environment or lifestyle and are therefore subject to change. Below you will find information on some lifestyle changes that may help increase your chances of natural conception or conception during infertility treatment.
Female reproductive function begins to decline many years before menopause, despite regular menstrual cycles. Women are born with a predetermined number of oocytes (eggs) in their ovaries that become depleted as they age. Infertility becomes more common after age 35. If you are over 35, we recommend that you seek help if you are unable to conceive after 6 months. Women under 35 may want to see a reproductive endocrinologist if they have been trying to conceive without success for more than a year. A number of factors can increase the risk of losing ovarian function earlier than expected. These factors include smoking, a family history of premature ovarian failure, and previous ovarian surgeries. The effects of age are not as pronounced in men, but there is an increased risk of certain genetic diseases and possibly autism for children conceived by men over 50.
Weight
Weight can be an important factor in determining a person's fertility. Both extremes, underweight and overweight, can contribute to ovulatory dysfunction and infertility. A body mass index (BMI = weight in kilograms / height in meters squared) of 25 to 29,9 is considered overweight, while a BMI of 30 and above is associated with obesity. A weight loss of just 5 to 10 percent of body mass can significantly improve ovulation and pregnancy rates. Obesity has been linked to an increased risk of miscarriage and lower success rates of fertility treatments.1 Obesity-related pregnancy problems include an increased risk of high blood pressure, diabetes, birth defects, and cesarean sections.2 Obese men have also been shown to have lower sperm quality.3 Caffeine4 In some studies, excessive coffee consumption has been linked to an increased risk of miscarriage. As a result, some recommend limiting consumption to 1 to 2 cups per day.
Smoking
Some studies have shown that smoking nearly doubles the risk of infertility. The evidence is consistent that the prevalence of infertility is higher, pregnancy rates are lower, and time to conception is longer in smokers than in non-smokers. Women who smoke begin menopause 1 to 4 years earlier than non-smokers. This is likely due to the harmful effects of chemicals in cigarette smoke on eggs, which accelerate their depletion. Smoking is also associated with an increased risk of miscarriage and ectopic pregnancy. Smokers undergoing IVF treatment are about 50% less likely than non-smokers to become pregnant. They must take higher doses of medication, produce fewer eggs, and have more cancelled cycles. Pregnant smokers are at higher risk of having low birth weight babies and delivering prematurely. Smoking has been associated with reductions in sperm concentration (on average by 22%), sperm motility, and potentially morphology (sperm shape) and function, although the evidence linking these to infertility is inconclusive. Smoking can also damage sperm DNA. Because of the risks associated with second-hand smoke in women, it is also recommended that men stop smoking.
Alcohol
Alcohol has been associated with hormonal and ovulatory abnormalities. However, the evidence regarding the link between the amount of alcohol consumed and infertility is inconclusive. Alcohol also has other adverse health effects; for this reason, the recommendation is < 1 to 2 drinks/day or < 9 drinks/week for women. As for alcohol consumption in men, it appears to be associated with a reduced chance of pregnancy when it exceeds 20 drinks/week. Despite these data, it is generally recommended to limit alcohol consumption to no more than 2 drinks per week for women and 4 for men.
Drug addicts
Drugs such as marijuana and cocaine can reduce fertility in men. Additionally, anything that increases the temperature around the testicles is thought to reduce fertility (i.e. tight pants, saunas, and hot baths).
Sexual relations
It is important to have regular intercourse (2 to 7 times/week) since prolonged abstinence (less than once a month) can reduce the chances of pregnancy by decreasing sperm count. In addition, certain vaginal lubricants (those containing petroleum jelly or Vaseline) should be avoided because they can be toxic to sperm. A small amount of mineral oil can be used when a lubricant is necessary.
Vitamins
A recent study from the Motherisk program at Children's Hospital showed that taking a prenatal vitamin significantly reduced the risk of certain birth defects and suggests that all women of childbearing age should take a multivitamin containing folic acid. For men, taking vitamin C (500 mg to 1 g/day), vitamin E (400 IU/day), and selenium (200 mcg/day) may help improve motility, while taking a multivitamin containing zinc (20 mg) may help promote sperm production. Folic acid (1 mg/day) is also recommended.
pharmaceuticals
Some prescription medications may be linked to infertility. It is important to discuss all medications, prescription or over-the-counter, with your doctor.
Having a healthy lifestyle, including regular physical activity, a balanced diet and stress reduction, as well as avoiding smoking and excessive alcohol consumption, will help you create the optimal conditions for achieving a healthy and successful pregnancy.
1 Oxford Journals, Human Reproduction, Obesity is associated with increased risk of first trimester and recurrent miscarriage: matched case-control study, March 2004
2 Mayo Clinic, March 2015
3 Spermatogenesis, Impact of obesity on male fertility, sperm function and molecular composition, October 2012
4 The Fertility Society of Australia, Pre-conception Health Special Interest Group, Effects of caffeine, alcohol and smoking on fertility
