A Closer Look at Alcohol and Fertility: How Much Is Too Much?
We have all been warned against drinking alcohol during pregnancy. After you drink your glass of wine, the alcohol can travel through the placenta, which supplies the fetus with the oxygen and nutrients it needs to grow. The alcohol then enters the fetus’ bloodstream. Our bodies have the capacity to process alcohol and eliminate it from our bodies through metabolism, but the fetus is not quite up to the task. As a result, some unstable compounds accumulate and can interfere with fetal head and brain development at each stage of pregnancy. (1) This can lead to an array of physical, cognitive, and behavioral issues -- and even stillbirth in severe cases. Think of it like an airport: when there are five security lines at JFK, travelers moves through security fairly seamlessly. But when there is only one line, the system gets overwhelmed and congested, and everyone starts getting flustered about missing their flight.
So, what about drinking alcohol before you get pregnant? The studies addressing this question have provided mixed results. Typically, moderate alcohol use is classified as one drink or less a day, whereas heavy alcohol use is classified as at least eight drinks a week. (2) Part of the issue, though, is that studies define levels of alcohol consumption differently from one another, and study participants generally report how many drinks they consume every day or every week themselves. This makes it hard to compare or really draw any definitive conclusions. We do know that chronic liver disease from alcohol use can impact fertility in a variety of ways, from causing irregular periods to hormone imbalances. (3) But for people who have a few drinks a week, the effects are less clear. One study, for example, found that people who are heavy or moderate drinkers are more likely to undergo a fertility evaluation and take longer to get pregnant. Other studies have found no difference in ovulatory dysfunction whatsoever. (4,5) Binge drinking might actually be more harmful than having a few drinks over the course of several days. (6,7)
Data for people undergoing fertility treatment are similarly mixed. Among individuals undergoing IVF, one study found that people who consumed at least four drinks a week had a 16% lower likelihood of achieving a live birth. (8) Another study showed a 13% decrease in the amount of oocytes that were retrieved. (9) Yet, other studies did not show any negative effects of moderate alcohol use on IVF outcomes. (10,11) Overall, it seems that drinking alcohol right before and during a treatment cycle may compromise your chances of a successful pregnancy. But a few alcoholic beverages a week, let’s say, in the year before starting a cycle probably does not play much of a role. (12) For partners, some studies have shown that excessive drinking in the month (and especially in the week) before sperm collection has been associated with lower chances of a successful pregnancy. (13)
So, long story short: it is hard to know what a “safe” amount of alcohol is during and even before pregnancy. Until we have more information, it is better to be thoughtful about alcohol consumption as you are attempting to conceive. Focusing on your health now can help you ensure that your pregnancy is as healthy as possible in the long run.
(1) Van Heertum, K., & Rossi, B. (2017). Alcohol and fertility: how much is too much?. Fertility research and practice, 3(1), 1-7.
(3) de Angelis, C., Nardone, A., Garifalos, F., Pivonello, C., Sansone, A., Conforti, A., ... & Pivonello, R. (2020). Smoke, alcohol and drug addiction and female fertility. Reproductive Biology and Endocrinology, 18(1), 1-26.
(4)Tolstrup, J. S., Kjær, S. K., Holst, C., Sharif, H., Munk, C., Osler, M., ... & GrØnbÆk, M. (2003). Alcohol use as predictor for infertility in a representative population of Danish women. Acta obstetricia et gynecologica Scandinavica, 82(8), 744-749.
(5) Chavarro, J. E., Rich-Edwards, J. W., Rosner, B. A., & Willett, W. C. (2009). Caffeinated and alcoholic beverage intake in relation to ovulatory disorder infertility. Epidemiology (Cambridge, Mass.), 20(3), 374.
(6) Maier, S. E., & West, J. R. (2001). Drinking patterns and alcohol-related birth defects. Alcohol Research & Health, 25(3), 168.
(7) Bailey, B. N., Delaney-Black, V., Covington, C. Y., Ager, J., Janisse, J., Hannigan, J. H., & Sokol, R. J. (2004). Prenatal exposure to binge drinking and cognitive and behavioral outcomes at age 7 years. American journal of obstetrics and gynecology, 191(3), 1037-1043.
(8) Rossi, B. V., Berry, K. F., Hornstein, M. D., Cramer, D. W., Ehrlich, S., & Missmer, S. A. (2011). Effect of alcohol consumption on in vitro fertilization. Obstetrics and gynecology, 117(1), 136.
Rossi BV, Berry KF, Hornstein MD, Cramer DW, Ehrlich S, Missmer SA
(9) Van Heertum, K., & Rossi, B. (2017). Alcohol and fertility: how much is too much?. Fertility research and practice, 3(1), 1-7.
(10) Abadia, L., Chiu, Y. H., Williams, P. L., Toth, T. L., Souter, I., Hauser, R., ... & EARTH Study Team. (2017). The association between pre-treatment maternal alcohol and caffeine intake and outcomes of assisted reproduction in a prospectively followed cohort. Human Reproduction, 32(9), 1846-1854.
(11) Lyngsø, J., Ramlau-Hansen, C. H., Bay, B., Ingerslev, H. J., Strandberg-Larsen, K., & Kesmodel, U. S. (2019). Low-to-moderate alcohol consumption and success in fertility treatment: a Danish cohort study. Human Reproduction, 34(7), 1334-1344.
(12) Mínguez-Alarcón, L., Chavarro, J. E., & Gaskins, A. J. (2018). Caffeine, alcohol, smoking, and reproductive outcomes among couples undergoing assisted reproductive technology treatments. Fertility and sterility, 110(4), 587-592.
(13) Van Heertum, K., & Rossi, B. (2017). Alcohol and fertility: how much is too much?. Fertility research and practice, 3(1), 1-