Nutrition, Exercise and More
Fertility Facts: Health and Lifestyle Factors
We all know that people that are not particularly health-conscious can conceive, many times easily or even unintentionally. However, conception is a much more common event when the involved parties are young because this is when eggs and sperm are much more likely to be genetically normal. It may also be that the reproductive system has not been subjected to years of accumulated age-related, environmental damage. Successful conception does not just involve eggs and sperm and the reproductive tract. Just as in all other areas of human physiology, the reproductive system works best when the entire organism is healthy and balanced. This includes not just physical health, but mental health and sexual health.
It makes sense that healthy people are more likely to have healthier babies, and this may be especially true in the later reproductive years. For example, a woman in her forties with mild high blood pressure is going to have a safer pregnancy when she keeps her weight down and consistently takes her medications for blood pressure. Similarly, the liver function may be negatively affected by the cumulative effects of drinking alcohol over many years and the liver is crucial to clearing toxins from the body.
The feeling of lack of control is one of the main issues for women and men facing the challenge of infertility. No one can know exactly when they are going to conceive, but for infertility patients undergoing fertility treatments, even the how of conception is being determined by medical factors that again are out of their control. One way to gain back some control is to take charge of our health and nutrition. Eating healthy and living healthy can only help one's chances for successful conception. Furthermore, when a pregnancy is achieved, the habits set prior to conception and continued during gestation will provide for the best physical environment to nurture the developing fetus. Here you will learn about nutritional needs during pre-conception and early pregnancy. The goal of pre-conception nutrition is to promote the health of the gametes (eggs and sperm) and to set the nutritional habits that will carry on into pregnancy and beyond to breast feeding.
DNA, Healthy Eggs and Sperm and our Environment
Certainly the most important component in eggs and sperm is the DNA, which carries the genetic material from the parents to the embryo. DNA molecules are long linear chains of nucleic acids, sugars and proteins. Damage to and degradation of DNA is a consequence of living. The energy packets in all our body's cells, including sperm and eggs, are called mitochondria. Mitochondria contain DNA and produce important enzymes for metabolism and energy production. Molecular by-products of metabolism, oxygen free radicals and nitric oxide species, are constantly forming in our bodies. These free radicals can damage both nuclear and mitochondrial DNA. All living organisms have developed many mechanisms to protect their DNA from the environmental damage of excessive nitric oxide and oxygen free radicals. Anti-oxidant nutrients and vitamins are essential to support these protective mechanisms. Truth be told, we all should be ingesting anti-oxidants throughout our lives to protect our DNA and all our tissues from assaults from the outer (and inner) world, but no time is more crucial for the next generation than at conception and fetal development.
There are known substances and chemicals in the modern world that can overwhelm our highly evolved physiologic protective processes. Just one well-known example is phthalate ester, a chemical used to soften plastics such as in disposable water bottles, which leaches into the water it contains. These phthalates have been shown to have toxic effects in animal studies on the reproductive system1 and have been found in urine and breast milk of pregnant and lactating women2. Unfortunately, phthalates are only one of many, many chemicals we are exposed to on a regular basis. So, there are substances to avoid, when possible, but can we really avoid every harmful chemical? Not likely. What we can do, beyond avoiding the obvious chemicals, is make sure we are getting the nutrients, vitamins and minerals that help our own enzymes and proteins to protect our DNA.
Diet – What to Eat? What to Avoid?
There are numerous books on nutrition for pre-pregnancy and pregnancy. It is not possible to cover this topic exhaustively in this article. Suffice it to say that there is no one diet that has been conclusively shown to promote fertility. It is common sense that nutritionally empty diets, especially those that promote obesity, are clearly harmful to conception. The fact is, diets lacking in essential vitamins and minerals can have consequences beyond infertility, such as very poor pregnancy outcomes and malnourished babies.
One recent article from the Netherlands3 looked at the diets of women undergoing IVF. They measured blood levels and follicular fluid levels of some essential vitamins and minerals in these women. To paraphrase their findings: In women, two dietary patterns were identified. The "health conscious–low processed” dietary pattern was characterized by high intakes of fruits, vegetables, fish, and whole grains and low intakes of snacks, meats, and mayonnaise, and positively correlated with red blood cell folate (β = 0.07). The "Mediterranean” dietary pattern that is, high intakes of vegetable oils, vegetables, fish, and legumes and low intakes of snacks, was positively correlated with red blood cell folate (β = 0.13), and vitamin B6 in blood (β = 0.09) and follicular fluid (β = 0.18). High adherence to the "Mediterranean” diet increased the probability of pregnancy by 40%. Their conclusion was "A preconception "Mediterranean” diet by couples undergoing IVF/ICSI treatment contributes to the success of achieving pregnancy.”
So avoiding environmental toxins and eating a healthy (possibly "Mediterranean”) diet may be helpful for general health, fertility and pregnancy, but what are the specifics? What to avoid? What to include? For some very general guidelines, see below. For more comprehensive help, we recommend the book "Fertility and Conception” by Dr. Karen Trewinnard4, listed in the References.
What to Avoid (a much-abbreviated list):
- Drinking from plastic water bottles.
- Microwaving food in plastic (and especially stryofoam!) containers
- Pesticides and herbicides – whenever possible, buy organic, when not possible, wash fruits and vegetables well
- Heavy metals such as lead (soldering, stripping old paint from walls), mercury (in high-food chain fish) and cadmium (cigarettes, solder materials, pesticides)
- White foods: too much white bread, refined sugar, white rice, potatoes
- Too much salt and butter, fried foods
- Caffeine – it's a blood vessel constrictor
- Alcohol – it's dehydrating and metabolites can be toxic but one or two glasses of wine or beer when not pregnant can be permitted.
What to Include (somewhat abbreviated):
- Olive oil rather than butter
- Fish that do not contain mercury (e.g. salmon, most shellfish, halibut, flounder)
- Organically-grown fresh fruit and vegetables
- Whole grains
- Omega-3 Fish oils
- Anti-oxidants such as blueberries, cranberries, tomatoes (lycopene)
- Pre-conception and pre-natal vitamins containing at least 800 mcg folic acid and 2000 IU of Vitamin D3 (for a more thorough discussion of the essential vitamins and minerals, click here.
- Plenty of fresh water – stay hydrated!
Exercise and Sexual Activity
With respect to physical health, most of what we should be doing is just common sense. For women, mild to moderate regular exercise is best. Although data on the level of exercise that is optimal for conception is scarce, probably no more than 4 hours per week of aerobic exercise may be best4. Much higher levels can lead to too low a level of body fat for women (optimal body fat for women should be about 20% of total body weight). Excessively lean women (less than 10%) have more problems with proper reproductive hormonal functioning when it comes to ovulation. And while speculative, it is likely humans evolved mechanisms to limit female reproduction in times of starvation (low body fat may mimic a starvation mode) and when we are too much on the run as well.
A study published in 2002 looked for associations between exercise levels and pregnancy and birth outcomes in exercising pregnant women5. The study reported that women who exercised heavily during pregnancy had smaller babies, more labor inductions and longer labor and well as more colds and flu than more sedentary pregnant women. These are surprising results! Despite these studies it is likely that some moderate amount of exercise helps to promote a sense of well-being and the mental composure to deal with the stresses of every day life and the stress of dealing with fertility issues. Cardiovascular fitness can only be a good thing for pregnancy and beyond.
For men, there really are no restrictions on physical activity. The one exception would be too much bicycling for men hoping to conceive with their partner. The current bicycle saddles do affect testicular function in men who are frequent riders. In general, maintaining good physical shape enhances sexual functioning and of course, sex is important for conception! Speaking of sex, for men to have optimal sexual health, it is important to avoid excessive alcohol. While alcohol does lower mental inhibitions, it also inhibits erectile function, so excess alcohol, contrary to popular belief, does not enhance the sexual experience. Long term excessive alcohol also causes liver damage and raises estrogen levels in men. Higher estrogen levels can lead to smaller testicular volume and lowered sperm production. There is no problem with an occasional drink – just be aware of how much. Avoid intoxication, dehydration, hangovers, and the other consequences of excessive alcohol intake. Anti-oxidant nutritional supplements are critical to helping maintain optimum sperm health.
As many of our patients are aware, the experience of trying to conceive, especially if it's taking a long time, can take a toll on sex and intimacy in a relationship. It is so important for partners to be patient with each other and make the effort to maintain the romance and intimacy which keep the relationship healthy. Yes, plan to have sex on the most fertile days of the month, but don't stop having it before and after the fertile times as well. There is no medical evidence that sex is harmful during the post-ovulation or early pregnancy period. Try to keep the sex-as-fun-and-special attitude alive throughout the month, including baby-making sex days. If there are stresses associated with this issue, we can provide referrals to psychologists that specialize in counseling about sexual health and are professionals in this area. Remember that our sex lives will outlive the infertility, the new baby and the growing children experiences. So it is crucial to nurture this aspect of the relationship.
There is no question that having a good sexual relationship promotes intimacy and better communication. This is so important when it comes to supporting each other. Fertility problems can be a crisis time in the lives of young adults. Sometimes the crisis situation can bring a couple closer together and sometimes it can cause them to feel isolated, even from each other. Communication is essential. For most women, communication is usually inherently verbal; she wants to talk about it and about her feelings. For most men, dealing with painful feelings, such as that recent negative pregnancy test or that recent miscarriage can be difficult for him to verbalize. Add to this frustration, the obvious sorrow of his female partner and men can feel helpless. It doesn't necessarily help to try to force people to talk about these feelings, at least until they are ready. Letting him go the gym or shoot some hoops with some friends might be a better way for him to initially deal with bad news. But when the time comes, talking and acknowledging each other's feelings and understanding how each person deals with difficult situations can make a relationship much stronger.
- Phthalates: toxicogenomics and inferred human diseases. Genomics. 2011 Mar; 97(3):148-57. Epub 2010 Dec 13. Singh S, Li SS Department of Life Science, College of Science, National Taiwan Normal University, Taipei 116, Taiwan. [email protected]
- Phthalate exposure in pregnant women and their children in central Taiwan. Lin S, Ku HY, Su PH, Chen JW, Huang PC, Angerer J, Wang SL. Chemosphere. 2011 Feb;82(7):947-55. Epub 2010 Nov 13
- The preconception Mediterranean dietary pattern in couples undergoing in vitro fertilization/intracytoplasmic sperm injection treatment increases the chance of pregnancy. Fertility and Sterility Volume 94, Issue 6 , Pages 2096-2101, November 2010. Marijana Vujkovic, B.Sc. Jeanne H. de Vries, Ph.D. Jan Lindemans, Ph.D. Nick S. Macklon, Ph.D. Peter J. van der Spek, Ph.D. Eric A.P. Steegers, Ph.D. ,Régine P.M. Steegers-Theunissen, Ph.D.
- Fertility and Conception – The essential guide to natural ways to boost your fertility and conceive a healthy baby – from learning your fertility signals to adopting a healthier lifestyle. By Dr. Karen Trewinnard BM FFSRH, Carroll and Brown Publishers, Ltd.
- Effects of Lifetime Exercise on the Outcome of In Vitro Fertilization Morris, Stephanie N.; Missmer, Stacey A.; Cramer, Daniel W.; Powers, R Douglas; McShane, Patricia M.; Hornstein, Mark D.Obstetrics & Gynecology. 108(4):938-945, October 2006.
- Antpartum, Intrapartum, and Neonatal Significance of Exercise on Healthy, Low-Risk Pregnant Working Women. Maqgtann, Everett F., Evans, Sharon F., Weitz, Beth, Newnham, John. Obstetrics & Gynecology. 99(3):466-472. March 2002.