Caffeine has long been on the list of substances that women who are pregnant should not consume. Regardless of the source, be it coffee, soft drinks, or even hot chocolate, caffeine has seemingly always been associated with pregnancy problems. For years though, studies that looked at the impact of caffeine on a woman’s body during pregnancy failed to account for several variables and symptoms that often disguised the true effects of caffeine on a pregnant woman’s body, in particular as its effects relate to miscarriage.
A 2008 study conducted by Kaiser Permanente Division of Research successfully controlled for these variables, specifically nausea, vomiting, and caffeine aversion, and successfully found a considerable link between caffeine and miscarriage. Unlike previous studies, the once conducted by Kaiser successfully controlled the factors that inspire women to avoid caffeine during pregnancy. As a result, the long-suspected correlation between caffeine and miscarriage was strengthened, especially since it has long been speculated that any correlation was the result of reduced caffeine consumption.
In looking at more than one thousand members, Kaiser found that women who consumed more than 200 milligrams of caffeine or more a day actually increased their risk of miscarriage. This amount, which represents about two cups of coffee or five cans of soda, made consumers twice more likely to miscarry than women who did not consume caffeine during their pregnancy.
By considering other sources of caffeine, including soft drinks, tea, and hot chocolate, researchers were able to establish that the increased risk of miscarriage were in fact due to the consumption of caffeine and not to any other sources. For years, the association between caffeine and miscarriage had been related to caffeine avoidance on the part of healthy women. However, the study clearly indicates that for pregnant women, or women looking to become pregnant, the consumption of caffeine should definitely be eliminated or avoided during pregnancy, especially if they want to avoid a potential miscarriage.
Researchers have long looked at the specifics of how caffeine can affect a developing fetus, and the answers are relatively simple. Caffeine can actually cross from the placenta to the fetus, and when it enters the body, the fetus and its underdeveloped metabolism are not able to break down the caffeine the way adults and older children can. In addition, caffeine might also play a role in improper cell development and a lack of blood flow to the placenta, both of which can increase the risk of miscarriage.
Despite the potential for miscarriage, researchers understand that oftentimes, women who are pregnant need a way of fighting the stress and fatigue that often come with a pregnancy. Their recommendation is to limit the intake of caffeine to no more than a cup or less a day, though they again stress that caffeine should be avoided altogether. One Kaiser representative encouraged women to seek other methods of cheering up and fighting stress, including walking, doing yoga, or snacking on healthy dried fruits.
- Kaiser Permanente Division of Research. “Caffeine is linked to miscarriage risk, new study shows.” ScienceDaily. ScienceDaily, 22 January 2008. Retrieved from www.sciencedaily.com/releases/2008/01/080121080402.htm
Hethir Rodriguez is the Founder and President of Natural Fertility Info.com. She has been a Certified Herbalist for over 19 years, holds a Bachelors degree (BS) in Nutrition Sciences and is a Certified Birth Doula. Since founding Natural Fertility Info.com in 2007, Hethir has written and co-authored over 1200+ articles on Fertility; and her research, articles, and guides have been read by over 40,000,000 people. Hethir has dedicated her life to helping provide a source for high quality, research based information and support for those on their journey to becoming parents.
Hello,
I was wondering if any studies have looked at tea, specifically green tea, and whether or not there is a correlation between consuming tea and miscarriage. I feel like there are hardly any studies that have looked at that.
Dear Hyatt,
We offer two guides on green tea:
Green Tea Consumption May Lower the Body’s Ability to Absorb Folic Acid
Green Tea – Do I Really Have to Avoid it in Pregnancy?
I don’t know of conclusive studies linking green tea directly to miscarriage for every woman. I just can not believe that would be a cause (my opinion). This wasn’t the case for me personally (I drink green tea daily and did through two healthy pregnancies), or that it could be cause given so many growing cultures consumes green tea regularly.