Life choices and fertility

Please note: We have listed some key references in the discussion below, but you may wish to review our references list. We have added a discussion for each study so you can appreciate the evidence behind our recommendations.

Fertility requires the male and female gametes (the sperm and the eggs) to be very healthy. Unfortunately as men and women age, both the sperm and the eggs are less able to form an embryo that can implant and form a normal offspring. In the past, the marked reduction of fertility with age was attributed only to the female, but in large studies where it has been possible to control for female age, and in studies of recipients of donated eggs from young egg donors, successful pregnancy occurs less often as the age of the male partner increases (de la Rochebrochard, 2006).

The gonads (the testicle and the ovary) need a good blood supply, just as the penis needs good blood flow for normal erectile function (see all of the other pages on this site). A good blood supply brings more nutrients, oxygen and hormones to the testicles and ovaries so that their function can be optimized. For example, in the male, two agents known to increase nitric oxide, and therefore blood flow, increased the level of testosterone in the bloodstream and also significantly improved semen volume, sperm numbers, sperm motility, and sperm morphology (Stanislovov, 2008, 2009). Testosterone production within the testicle is an important stimulator of normal sperm production. In the female, blood flow to the ovary correlates with the number of eggs that develop when the ovary is stimulated, and the quality of the egg and the chance of it initiating a pregnancy has been correlated with the blood supply surrounding the mature follicle (the structure containing the egg and its nourishing cells, the granulosa cells) (Lozano, 2007). Therefore all of the factors regarding increasing blood supply for good erectile function discussed in other pages on this site can be expected to also improve blood supply to the testicles and ovaries. The specific regimen that improved testicular function mentioned above was a combination of 3 grams daily of L-arginine and 80 mg of pycnogenol. L-citrulline at a dose of 2 grams per day raises the circulating levels of L-arginine more than 3 grams of L-arginine and therefore should have the same or a greater effect because it also acts as an intracellular source of L-arginine.

The antioxidant capacity of the semen and of the fluid and cells surrounding the egg decreases with age and is lower in individuals with poor sperm and egg quality. It is not known why the antioxidant capacity decreases with age, but advanced glycation end-products may play a role (Jinno, 2008). These potent oxidants increase with age and accumulate from eating foods cooked at a high heat such as with grilling and barbecuing. In the male, oxidation products correlate with poor semen parameters, particularly motility, and correlate also with fragmentation of the sperm DNA. Sperm require high levels of antioxidants in the surrounding fluid because as they shed cytoplasm to make them more motile, they lose their normal intracellular antioxidant defenses. In the female, oxidation products correlate with less viability of the granulosa cells, which surround and nourish the egg. In studies of in vitro fertilization, poor viability of those cells correlates very strongly with poor egg and embryo quality and pregnancy outcome (Li, Elgindy, 2008). Again, all of the antioxidants we suggest for improving erectile function would be excellent choices for maximizing fertility in both sexes. However, for the female, we do not recommend chocolate, because of its content of caffeine, or wine due to the alcohol. Also for the female we suggest only one cup of decaffeinated green tea per day, but the absorption of antioxidants (but not caffeine) can be markedly enhanced by adding 50 mg of Vitamin C (Green, 2007) to each cup see( female fertility supplements). In the male, more Vitamin C and Vitamin E may be helpful to minimize fragmentation of the DNA of the sperm. In a well-designed study, 1000 mg of Vitamin C and 1000 mg of Vitamin E (1 unit equals 1 mg of dl-alpha tocopherol, but only 0.6 mg of d-alpha tocopherol; unfortunately these authors did not state which form of vitamin E was used) decreased the percentage of the sperm having fragmented DNA from 22% to 9%, whereas it was unchanged with placebo (Greco, 2005). Sperm fragmentation increases with age (Schmid, 2007, Quant, 2009, Tirado, 2009), particularly over age 40. Because the antioxidant capacity of 1000 mg of vitamin C is similar to that of 40 mg of pycnogenol, the dose of pycnogenol (see Stanislovov) can logically be reduced to 40-60 mg, which decreases cost (see male fertility supplements). Long term ingestion of 400 IU or more of vitamin E has been implicated in reduced overall health, but no short term adverse effects would be expected with 1,000 IU. If you are concerned, reduce the vitamin E to 200 IU and use the full 80-120 mg of pycnogenol. CAUTION vitamin E supplements should not be used by people who are taking aspirin. Vitamin E adds to the ant-clotting effect of aspirin. Use the higher dose of pycnogenol instead of the vitamin E if you take aspirin (women commonly are given low dose aspirin during fertility treatments).

A better diet with more antioxidants, fruits and vegetables and less meat, dairy and processed products has been correlated with better semen quality (Mendiola, 2009). These findings further support the positive impact of the suggested supplements see( male fertility supplements). Both the sperm and the eggs require a very high level of energy production. For the sperm, energy is needed for motility. For the egg, energy is needed for the proper segregation of the chromosomes and to expel one of each pair so that they can match up with the 23 chromosomes of the sperm to yield the 46 chromosomes of the adult cell. It is disruptions of that process that result in the higher miscarriage rate and contribute to the lower success rate of older couples. A high level of energy is also required for cell division into an embryo and by the rapidly dividing embryo. The oocyte has very high levels of energy-producing mitochondria, and oocyte mitochondrial DNA increases enormously during follicular growth. The mitochondrial DNA existing in the fully mature oocyte must be sufficient for the many cells of the embryo to function and continue to divide, because mitochondria do not replicate until the blastocyst stage. The older egg has lower levels of mitochondrial DNA and energy. Co-enzyme Q-10 (see female fertility supplements) is critical to the transport of electrons and protons involved in the chemical reactions that drive ATP and therefore energy production. This mitochondrial nutrient has been shown to reverse the effects of aging in the older female rat, including improved chromosome segregation. Although not yet evaluated in the older female to improve fertility, supplements of Q-10 have been used in a number of other studies with no side effects or adverse events being reported. Q-10 has also been reported to increase sperm motility (see male fertility supplements).

Excess body weight has major effects on female fertility but relatively minor effects on sperm quality. See weight and fertility for a detailed discussion of the effects of weight on ovulation, miscarriage, and achieving a successful pregnancy for the female. A high protein diet has been correlated with decreased fertility in animal studies. The higher concentration of ammonia found in reproductive tissue may inhibit embryo development or cause abnormal gene function.

Exercise has only positive effects for the male, but in one study from Harvard (Morris, 2006), more than three hours of aerobic exercise per week for the female was associated with a reduced pregnancy rate with IVF. Until this is clarified by further studies we suggest only the standard 30 minutes of moderate exercise (such as a brisk walk) most days of the week that is advised for good general health. It is possible that the stress on the body of greater degrees of exercise may add together with the stress of infertility and produce an adverse effect.

There has been relatively little study of the effects of the environment on fertility. It has long been known that lead, cadmium and some pesticides adversely affect sperm quality, and a recent study suggested that having a cell phone in a front pant pocket transmitting to an earpiece may influence sperm quality through cell phone radiation. A recent study correlated the levels of bisphenol-A (Mok-Lin, 2009), which is an endocrine disruptor that leaches out of some plastic water bottles, with reduced ovarian response to stimulation.

Smoking has major adverse effects on both sperm and egg quality. With female smoking, natural fertility is decreased and the chance of successful pregnancy with IVF is decreased by 50% (Hughes, 1994). Although one would assume that the effects are lesser in degree, second-hand smoke was found to have a similar effect on the outcome of IVF compared with smoking (Neal, 2005). The effect is not only on egg quality. Recipients of egg donation who smoke also have a significantly lower pregnancy rate (Soares, 2007). In the male, smoking increases sperm DNA fragmentation, which can increase miscarriage and may help to explain why male smoking decreases IVF success by a third, even when a sperm is directly inserted into each egg (Zitzmann, 2003). Female smoking also increases miscarriage. Exposure of infants and young children to second-hand smoke increases asthma, bronchitis, pneumonia, ear infections, and sudden infant death syndrome. For anyone to continue to smoke while trying to conceive is being self-defeating and completely illogical.

Alcohol also reduces fertility in both partners (Rossi, 2009) and alcohol intake by the male may increase miscarriage (Klonoff-Cohen, 2003) In one study small amounts of caffeine and alcohol appeared to have additive or even synergistic effects (Hakim, 1998). As with most adverse life choices, the effects appear to be greater with the more advanced procedure of IVF. With the exception of couples just beginning to attempt conception, avoiding alcohol will give them the greatest chance for being successful.

Caffeine intake does not appear to affect male fertility unless it is excessive (over 3 cups of caffeinated coffee per day). However, female fertility is influenced to a greater degree, with moderate amounts reducing fertility and any significant intake reducing the success with IVF (Klonoff-Cohen, 2002). Caffeine should not be used by pregnant women as it has been associated with miscarriage.

Frequency of intercourse certainly is very important in attempting to conceive. The recommended frequency is every one to two days around the expected time of ovulation. More frequent ejaculation may also be helpful before IVF or ICSI by decreasing sperm DNA fragmentation. More frequent erections may also decrease the later development of erectile dysfunction. In a study of men aged 55 to 75, a two-fold incidence of ED was noted with less frequent coitus (Koskimaki, 2008).

Although there have been many empirical suggestions to try to improve the contact of sperm with cervical mucus before and following intercourse such as placing a pillow under the buttocks, there have been no studies to substantiate such effects, and sperm have been found in pelvic fluid within five minutes of being placed on the cervix. Nevertheless, it is usually recommended for the female to remain supine for 15-20 minutes to maximize sperm migration. Likewise although vaginal lubricants theoretically may interfere with sperm viability there have been no actual studies to show such an effect with intercourse. There is a product that has no adverse effect on sperm (preseed) that is commonly recommended when a sexual lubricant is needed.

Finally, any discussion of life choices and fertility would be incomplete without discussing the effects of anxiety, stress, and depression. Various studies have shown a reduced success rate in achieving pregnancy in women experiencing these symptoms (Sanders 1999, Smeenk 2001, Klonoff-Cohen 2001, Ebbesen 2009), and an intensive stress reduction program (mind/body) has been shown in controlled studies to reduce the time to achieve a pregnancy in couples just beginning to attempt conception and to increase the pregnancy rate with IVF (Domar 2009). One study showed that certain individuals are more vulnerable to stress (Faccinetti 1997). When exposed to stressful visual and auditory stimuli, those exhibiting greater increases of their pulse and blood pressure had a reduced chance of pregnancy. This study also indicated that reduced blood flow may be the mechanism through which such an effect is manifested. Stress can also be reduced by taking on fewer tasks, by techniques such as yoga, or even taking off time from work during the ovarian stimulation through until well after embryo transfer, as full-time employment has been correlated with a lower pregnancy rate with IVF.

It should be apparent from the above discussion that there are many lifestyle choices a couple can modify to increase their chances of being successful. Ideally these should be altered when beginning to try to conceive, but all of these factors become progressively more important as the fertility treatments become more involved. Also keep in mind the changes you are able to achieve will improve your general health for many years to come (see other health benefits).