Fertility and Miscarriage

According to statistics compiled by the Centers for Disease Control, 6.1 million women in the US between the ages of 15 and 44 have an impaired ability to have children. More than nine million women utilitze infertility services to increase their chances of becoming pregnant. Caffeine and coffee negatively affect fertility through more than one mechanism, particularly in caffeine senstive women.

Caffeine and Coffee Increases Inferility

• While many factors affect fertility, cigarette smoking, alcohol drinking and caffeine consumption are linked to decreased ability to get pregnant and carry a fetus to term. (Jensen, et al, 1998) (Florack, et al, 1994) (Wilcox, et al, 1998)
• Additionally, caffeine has been shown to interfere with the ability of the fertilized egg to implant in the uterus,  a process that is necessary for pregnancy to progress. (Pollard, et al, 1999)

Caffeine Consumption Increases The Risk of Miscarriage

• Caffeine intake during the first trimester has shown a strong association with late miscarriage and stillbirth with more than 100 mg of caffeine per day (1 cup of coffee)  in a group of more than 2,000 women studied in the U.K. (Greenwood, D.C., et al, 2010)
• Higher amounts of caffeine consumed during pregnancy increase the risk of miscarriage according to another study conducted at Kaiser Permanente in Northern California and published in the American Journal of Obstetrics and Gynecology. This is unrelated to the presence of symptoms such as nausea. (Weng, et al, 2008)
• Genetic differences affect the rate of metabolism of caffeine in the liver. Some investigations suggest that these differences in genetics may increase the risk of miscarriage in people with the slow caffeine metabolizing gene when combined with higher caffeine intake. (Karypidis, A.H., et al, 2006).

References (by alphabetical order)

Florack, E.I., Zielhuis, G.A and Rolland, R. 1994. Cigarette smoking, alcohol consumption, and caffeine intake and fecundability. Preventative Medicine. 23(2):175-80.

Greenwood, D.C., Alwan, N., Boylan, S., Cade, J.E., Charvil, J., Chipps, K.C., Cooke, M.S., Dolby, V.A., Hay, A.W., Kassam, S., Kirk, S.F., Konje, J.C., Potdar, N., Shires, S., Simpson, N., Taub, N., Thomas, J.D., Walker, J., White, K.L., Wild, C.P. 2010. Caffeine intake during pregnancy, late miscarriage and stillbirth. European Journal of Epidemiology. March 21.

Jensen, T.K., Henriksen, T.B., Hjollund, N.H., Scheike, T., Kolstad, H., Giwercman, A., Ernst, E., Bonde, J.P., Skakkebaek, N.E. and Olsen, J. 1998. Caffeine intake and fecundability: a follow-up study among 430 Danish couples planning their first pregnancy. Reproductive Toxicology. 12(3):289-95.

Karypidis, A.H., Söderström, T., Nordmark, A., Granath, F., Cnattingius, S., Rane, A. 2006. Association of cytochrome P450 1B1 polymorphism with first-trimester miscarriage. Fertility and Sterility. 86(5): 1498-503.

Pollard, I., Murray, J.F., Hiller, R., Scaramuzzi, R.J. and Wilson, C.A. 1999. Effects of preconceptual caffeine exposure on pregnancy and progeny viability. The Journal of Maternal-Fetal Medicine. 8(5):220-4.

Weng, X., Odouli, R., Li, D.K. 2008. Maternal caffeine consumption during pregnancy and the risk of miscarriage: a prospective cohort study. American Journal of Obstetrics and Gynecology. 198(3): 279:e.

Wilcox, A., Weinberg, C. and Baird, D. 1998. Caffeinated beverages and decreased fertility. Lancet. 2(8626-8627):1453-6.