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The effects of caffeine on reproductive outcomes in women

Vicki Nisenblat, MD
Robert J Norman, MD
Section Editor
Charles J Lockwood, MD, MHCM
Deputy Editor
Kristen Eckler, MD, FACOG


Caffeine is the most popular pharmacologically active substance consumed and one of the most heavily researched commodities in the world. It is a stimulant, and is often used to enhance mental alertness.

Although there is no high quality evidence that a modest level of caffeine consumption has adverse effects on fertility or pregnancy outcome, putative beliefs about a relationship between caffeine intake and adverse reproductive outcomes are common, and caffeine consumption is often perceived to be an unhealthy habit. The consumption of caffeinated beverages has been implicated in fertility problems, while consumption during pregnancy has been associated with an increased risk of miscarriage, congenital malformations, fetal growth restriction, stillbirth, and long-term behavioral effects in offspring. The biologic rationale for these associations is caffeine's ability to accumulate in fetal tissues and produce diverse pharmacologic effects that could interfere with fetal growth and development [1,2].

This topic will review the relationship between caffeine intake and reproductive issues in women. The physiological effects of caffeine and caffeinated beverages and the effects of caffeine on specific disease processes, including insulin resistance, cancer, cardiovascular disease, and mortality are discussed separately. (See "Cardiovascular effects of caffeine and caffeinated beverages" and "Benefits and risks of caffeine and caffeinated beverages".)


Caffeine originates in more than 60 plants, occurs naturally in various food products and beverages (including coffee, tea, chocolate, cocoa products, colas), and is added to some soft drinks and most "energy" drinks. Caffeine is also present in some prescription and over-the-counter medications, such as cold and flu remedies, allergy and headache treatments, diet pills, diuretics, and stimulants. Increasingly, caffeine is now present as an additive in snack foods, sports performance supplements, and dietary supplements. Examples of the caffeine content of various products can be found online (eg, http://www.cspinet.org/new/cafchart.htm) and in the table (table 1).

Coffee, tea, cocoa and carbonated soft drinks are the main sources of caffeine intake. Consumption varies throughout the world, and is influenced by culture, individual preferences, availability, and advertising. Coffee contains 50 to 70 percent more caffeine than tea and other products, accounting for the main source of caffeine in many populations.

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Literature review current through: Nov 2017. | This topic last updated: Aug 25, 2017.
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