Will coffee cause infertility or harm fetal development? More than 10% reproductive age couples in America are experiencing fertility issues. As coffee is one of the most consumed beverages of American, the role of caffeinated beverages consumption on infertility has been widely concerned and studied.
Caffeine intake affects human hormone levels
Caffeine is an adenosine receptor antagonist and stimulant of the central nervous system. It provides short-term physiologic effects in the human body.
For women, Caffeine intake may lower luteal phase levels of estrogen and progesterone, increase the risk of short menstrual cycles, and has also been found to stimulate ovulation.
Male coffee/caffeine consumption has been associated with high levels of plasma testosterone and sex hormone binding globulin (SHBG). The elevated testosterone level could disrupt the endocrine system and have a negative effect on sperm production
Female reproductive health and caffeine intake
The relation of women caffeine intake and female reproductive health has been studied extensively. Researchers discovered inconsistent findings about infertility, but negative results on pregnancy outcomes.
The relation between female fertility and caffeine intake is not clear
Some prospective epidemiologic studies have found little relation between female caffeine intake and fertility. A 2016 study of caffeine and caffeinated beverage consumption and fecundability found caffeinated tea intake was associated with slight reductions in fecundability among females.
Caffeine intake negatively affects pregnancy outcomes and childhood health
· Miscarriage and stillbirth are related to caffeine intake.
Caffeine intake was found to increase the risk of miscarriage with daily consumption amount >100mg in some studies. Both Spontaneous abortion and recurrent miscarriage are found to inversely relate to caffeine intake.
It is reported that maternal caffeine intake during the first trimester was significantly associated with an increased stillbirth at ≥300 mg/day;
· Birth defects associated with maternal caffeine intake
Scientific studies found that caffeine intake increases the risk of birth defects and underlying etiologies.
· Caffeine intake may increase the risk of childhood acute leukemia
A 2014 study found maternal coffee consumption during pregnancy may be associated with childhood acute leukemia.
· Maternal caffeine raises the risk of childhood behavioral disorders
A 2017 study examined the association between maternal caffeine consumption from coffee and tea during pregnancy and offspring behavioral disorders. In their study, Maternal coffee consumption ≥8 cups/day at 15 weeks of gestation was associated with increased risk of hyperactivity-inattention disorder, conduct-oppositional disorders, and any psychiatric disorder. Maternal tea consumption ≥8 cups/day at 15 weeks of gestation was associated with increased risk of anxiety-depressive disorders and any psychiatric disorder.
· Child IQ/offspring brain development may be negatively affected by maternal caffeine intake
A 2016 published paper studied caffeine intake by women during pregnancy is associated with impaired cognitive development in offspring at age 5.5 years. Researchers found an association between caffeine intake during pregnancy and impaired cognitive development in offspring.
The 2017 behavioral disorder study mentioned above also concluded that maternal caffeine exposure may affect the fetal brain and later development.
· Maternal caffeine intake may raise the risk of childhood obesity
Maternal caffeine intake during pregnancy and risk of obesity in offspring was studied in a 2014 paper. A prospective study of pregnant women with 15 years follow-up of their offspring was conducted to examine the impact of in-utero exposure to caffeine on the risk of childhood obesity. An association of in-utero exposure to caffeine with an increased risk of childhood obesity was observed.
Male reproductive health negatively associates with caffeine intake
· Caffeine may cause sperm DNA damage
A paper reviewed 22 articles of male coffee/caffeine intake and reproductive outcomes. caffeine intake associated with aneuploidy and DNA breaks which lead to sperm DNA defects. Sperm DNA damage may negatively affect the male reproductive function
· Caffeine intake lower fecundability
The 2016 caffeine and caffeinated beverage consumption and fecundability study found that total caffeine intake among males was inversely associated with fecundability when comparing the total caffeine intake of 300 mg/day vs 100 mg/day. Caffeinated soda and energy drink intakes associated with reduced fecundability among males.
A review of 35 scientific papers concluded that caffeine intake detrimentally associates with male semen quality, and lower fecundability.
Limiting Caffeinated beverage intake for conception and pregnancy
As discussed above, scientific studies have shown sufficient evidence on the negative effects of caffeine intake on human reproductive health and childhood development in offspring. We recommend quitting caffeinated beverage for adults (both male and female) who are preparing conception and women during pregnancy. However, caffeine’s is a serious addiction. If it is too difficult for you to quit caffeinated beverage, a limited amount of 100 mg /day total caffeine intake is recommended, that is an 8-oz cup of coffee.