Staying Healthy Effects of Drinking in the First Few Weeks of Pregnancy By Buddy T facebook twitter Buddy T is an anonymous writer and founding member of the Online Al-Anon Outreach Committee with decades of experience writing about alcoholism. Learn about our editorial process Buddy T Medically reviewed by Medically reviewed by Steven Gans, MD on September 05, 2015 Steven Gans, MD is board-certified in psychiatry and is an active supervisor, teacher, and mentor at Massachusetts General Hospital. Learn about our Review Board Steven Gans, MD Updated on September 01, 2020 Print Your Pregnancy Week by Week Overview First Trimester Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Week 9 Week 10 Week 11 Week 12 Week 13 Second Trimester Week 14 Week 15 Week 16 Week 17 Week 18 Week 19 Week 20 Week 21 Week 22 Week 23 Week 24 Week 25 Week 26 Week 27 Third Trimester Week 28 Week 29 Week 30 Week 31 Week 32 Week 33 Week 34 Week 35 Week 36 Week 37 Week 38 Week 39 Week 40 Westend61 / Getty Images If you were consuming alcohol in the weeks before you learned that you were pregnant, you might be worried about the possible consequences. The early weeks of pregnancy are critical to embryo development but the research on the effect of drinking alcohol during this period is conflicting. Research on Alcohol in Early Pregnancy Some studies have suggested that consuming alcohol during the first few weeks of pregnancy can harm the development of the fetus. However, other studies have suggested that drinking during the early days of pregnancy does not harm a developing fetus. Research has also provided evidence that it's a person's pattern of drinking (for example, having one drink per day as opposed to binge drinking) that wields the most influence on the effect alcohol consumption has on fetal development. The Centers for Disease Control and Prevention (CDC) states that no amount of alcohol is safe during pregnancy. Key Time of Development Body systems and organs are developing during the embryonic stage of pregnancy which begins at fertilization and lasts through week 8. The heart, central nervous system, eyes, arms, and legs of the fetus are developing during the first four weeks of pregnancy—when many people are not yet aware that they are pregnant. These developing organ systems are more vulnerable to damage during the early stages of development. Drinking Pattern Is Significant Over the years, studies of fetal alcohol syndrome have found that a pregnant person's pattern of drinking has the greatest effect on a fetus. The most dangerous drinking patterns are chronic drinking, heavy drinking, and binge drinking. The pattern and timing of prenatal alcohol use can greatly influence the impact of adverse effects on the fetus, according to the CDC. Study Finds No Adverse Effects A study of 5,628 pregnant women in England, Ireland, New Zealand, and Australia found that women who drank during the early weeks of pregnancy were not at an increased risk for premature birth or low birth weight babies. The women also did not have an increased risk for high blood pressure complications during pregnancy. This study was met with a great deal of controversy when it was published in October 2013. The rates of premature birth and low-birth-weight babies for women who reported having seven or more drinks per week (about 15% of the group) were the same as the rates in women who did not drink. Is Low-Level Drinking Dangerous? A study of 1,264 pregnant women conducted a year later by the University of Leeds in England found that women who drank even low-level amounts of alcohol during the first weeks of pregnancy were at risk for having premature or unexpectedly small babies. Women who drank as few as two drinks a week had a greater risk of premature birth and low-weight birth than women who did not drink. A Word From Verywell It's unclear how alcohol consumed during early pregnancy will affect a fetus, but most health organizations advise people to stop drinking alcohol as soon as they intend to become pregnant or as soon as they find out that they are pregnant. Was this page helpful? Thanks for your feedback! Get diet and wellness tips to help your kids stay healthy and happy. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Johns Hopkins Medicine. The first trimester. Nykjaer, C. et al Maternal Alcohol Intake Prior to and During Pregnancy and Risk of Adverse Birth Outcomes: evidence from a British cohort. J Epidemiol Community Health. 2014;68:542-549. doi:10.1136/jech-2013-202934 The Centers for Disease Control and Prevention (CDC). Alcohol Use in Pregnancy. Updated April 30, 2020. Centers for Disease Control and Prevention. Fetal development chart. McCarthy, FP, et al Association Between Maternal Alcohol Consumption in Early Pregnancy and Pregnancy Outcomes. Obstet Gynecol. 2013;122(4):830-837. doi:10.1097/AOG.0b013e3182a6b226 Additional Reading Alcohol Use in Pregnancy. Centers for Disease Control and Prevention.