Overview
The prevention of disease is certainly more efficient and cost effective than its treatment. Nevertheless, human reproduction faces continued obstacles through lifestyles selected by patients often unwittingly. As healthcare professionals, we are responsible for educating our patients on reducing their risk of illness.
10-15% of the reproductive-aged population (approximately 6 million people) experience infertility.
In women, rarely a problem exceeds the importance during their reproductive years as fertility. To demonstrate the significance of this issue, the American Society for Reproductive Medicine (ASRM) established a public service announcement campaign, "Protect Your Fertility." (Since 10-15% of the reproductive-aged population (approximately 6 million people) experience infertility), this article is essential and will summarize the ASRM recommendations.
Here are the factors that increase the risk of infertility in both men and women:
- Smoking
- Sexually Transmitted Infections (STIs)
- Age
- Unhealthy body weight
ASRM recommendations:
Smoking
Currently, one-third of all men and women in this country smoke cigarettes and this behavior results in a 40 - 60% increase in infertility. Smoking accelerates follicular atresia and estradiol metabolism resulting in higher rates of miscarriages, ectopic pregnancies, and a several year earlier onset of menopause.
Considering Assisted Reproductive Technology (e.g. in vitro fertilization therapy), ovarian reserve, ovarian response to fertility medication, the number of oocytes retrieved and fertilized, and the pregnancy rates are reduced in smokers compared to non-smokers. The pregnancy rate in in vitro fertilization treatment cycles is decreased in smokers by 34%. The problem is not limited to women since sperm counts are reduced an average of 22%, and show a dose response with increased cigarette smoking correlating to a greater reduction in sperm count. Despite counts remaining in the normal range, sperm fertilization potential is reduced from smoking.
Smoking cessation prevents further damage and one study suggested that ex-smokers have fecundity similar to that of women who have never smoked, following one year of cessation. Unfortunately, the amount and duration of smoking has a significant effect on subsequent fertility, and it is not enough for just the patient to stop since passive smoke appears to be just as harmful.
A good cessation website is the American Lung Association.
STIs
If hypertension is considered the silent killer then STIs, particularly Chlamydia, is considered the silent killer of fertility by damaging the fallopian tubes. Although not practicing safe sex (specifically barrier contraception) may risk pregnancy, paradoxically it also risks subsequent infertility and ectopic pregnancy. The latter complication increases from a baseline of 2% to 8%. The incidence of tubal factor infertility increases 7-fold, 16-fold, and 28-fold, following one, two, and three infections to the fallopian tubes (salpingitis), respectively. Aggressive screening and prompt treatment may reduce the damage to reproductive potential.
Age
As more women are delaying childbirth and more "baby boomers" are reaching midlife, the problem of diminished ovarian reserve is increasing. Ovarian aging has several major medical consequences including decreased bone mass with risk of fracture, abnormal uterine bleeding from anovulation, infertility, and vasomotor symptoms.
The main impact on pregnancy rate is oocyte quality and quantity. As a result, fertilization is impaired, implantation is reduced, and miscarriage is increased along with the increased potential for chromosomal abnormalities of the fetus. Initiation of the first pregnancy should be encouraged to begin before the female turns 30 years of age.
"If a woman's body weight is less than 95% of predicted ideal body weight or greater than 120% of predicted ideal body weight, then weight management should be the primary therapeutic recommendation. More than 70% of women who are infertile as the result of body weight disorders will conceive spontaneously if their weight disorder is corrected through a weight-gaining or weight-reduction diet as appropriate."
Body Weight
Twelve percent of all infertility cases are a result of a woman being either over- or under-weight; the proportion is 6% from each. Weight is a critical factor in the hypothalamic pituitary axis and will influence the onset of puberty. The most common endocrinopathy from an elevated body mass index is Polycystic Ovarian Syndrome resulting in chronic ovulatory dysfunction and an increased risk of the metabolic syndrome. An extremely low body mass index can also affect ovulation dysfunction and is often associated with the female athlete triad (amenorrhea, bone loss, and eating disorder). In men, obesity results in a hormonal disturbance that decreases testosterone and sperm counts.
According to ASRM guidelines, "if a woman's body weight is less than 95% of predicted ideal body weight or greater than 120% of predicted ideal body weight, then weight management should be the primary therapeutic recommendation. More than 70% of women who are infertile as the result of body weight disorders will conceive spontaneously if their weight disorder is corrected through a weight-gaining or weight-reduction diet as appropriate."
Infertility Risks for Men
As mentioned, men are not immune from lifestyle risks affecting fertility and should follow the following recommendations: avoid drug use, smoking and excessive alcohol; avoid excessive scrotal temperature to prevent impaired spermatogenesis; and avoid STIs. Aging does plays a role in male fertility, though less clearly defined.
For more information on educating your patients to reduce their risk of infertility, please visit the ASRM sponsored website, http://www.protectyourfertility.com as well as their home page on human reproduction, http://www.asrm.org.
