Daily Tea Consumption Associated With a Lower Risk for Infertility

Female individuals who drink 0 to 2 cups of tea daily are at a lower risk for infertility, according to study results published in Reproductive Biology and Endocrinology.

In several countries, infertility is reported as high as 10% to 14%. Although previous research findings have suggested a link between caffeine intake and female fertility, these findings are inconsistent.  

To investigate the association between tea, coffee, and caffeine consumption and risk for female infertility, researchers conducted a cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES) between 2013 to 2018.

A total of 2099 nonpregnant female individuals aged 18 to 44 years were included and separated into fertile (n=1863) and infertile (n=236) groups. Inclusion criteria were sexual experience, sexual intercourse within the past 12 months, no infectious diseases of the reproductive system, and no history of bilateral oophorectomy and hysterectomy.

The researchers initially assessed participants’ tea, coffee, and caffeine consumption using the Dietary Data section of the NHANES, then followed up by telephone 3 to 10 days later for a second assessment. Participants’ age, body mass index (BMI), physical activity level, smoking/drinking status, and health history were also collected.

After adjustment for covariates, participants in the infertile vs fertile group were older (33.29 vs 30.01 years; P <.0006), had a higher BMI (32.12 vs 28.54 kg/m²; P =.0006), spent more time doing physical activity (1474.22 vs 1083.55 min/week; P =0.0365), were married and living with a partner (78.61% vs 58.41%; P <.0001), and had higher rates of hypertension (16.89% vs 9.87%; P =.0176) and diabetes (8.13% vs 2.59%; P <.0001).

Female individuals who consumed more than 0 but less than 2 cups of tea per day demonstrated a lower risk for infertility (odds ratio [OR], 0.55; 95% CI, 0.33-0.89; P =.0234). Additionally, the researchers reported no significant associations between coffee and caffeine consumption and infertility.

Using a 2-piecewise linear regression model, the researchers identified an inflection point value of 2. To the left of this inflection point, each additional cup of tea consumed was associated with further reduction in risk for infertility (OR, 0.73; 95% CI, 0.57-0.93; P =.0122). The association between tea consumption and infertility was not significant to the right of the inflection point.

Study limitations include the cross-sectional design, the exclusion of data from outside the United States, the inclusion of self-reported diet information, and the limited data on the quantity of water used to brew the tea.

“[W]e found a negative association between daily tea consumption ranging from more than 0 cups to less than 2 cups and infertility,” the researchers concluded. “Within this range, each additional cup of tea consumed was associated with a 27% reduction in the risk of infertility.”

This article originally appeared on Endocrinology Advisor