BACKGROUND AND PURPOSE:

• Data is limited regarding timing of alcohol cessation and impact on spontaneous abortion
• Sundermann et al. (AJOG, 2020) evaluated the association between week-by-week alcohol consumption in early pregnancy and spontaneous abortion

METHODS:

• Prospective cohort study (2000 to 2012)
  • Right from the Start study
• Participants
  • Pregnant participants from 8 metropolitan areas of the US
• Study design
  • In the first trimester participants provided information about alcohol consumed in the prior 4 months, including
    • Whether they altered their alcohol use
    • Date of change in use
    • Frequency, amount, and type of alcohol consumed before and after change
• Authors assessed
  • Association between spontaneous abortion and week of alcohol use
  • Cumulative weeks exposed
  • Number of drinks per week
  • Beverage type
  • Binge drinking (>4 drinks per episode)

RESULTS:

• 5353 participants
  • Reported alcohol use during early pregnancy: 49.7%
  • Miscarried: 12.0%
• Change in alcohol use
  • 2926 women reported a change in alcohol exposure within the month before conception or during the first trimester
  • 91.5% quit using alcohol | 8.0% decreased use | 0.5% increased use
  • Median gestational age at change in alcohol use: 29 days (IQR 15 to 35 days)
• Alcohol use during gestational weeks 5 through 10 was associated with an increased spontaneous abortion risk
  • The risk peaked for use in week 9
• For every successive week of alcohol use there was an 8% increase in spontaneous abortion, compared to those who did not drink
  • Adjusted hazard ratio: 1.08 (95% CI, 1.04 to 1.12)
• Risk was not related to number of drinks per week, beverage type, or binge drinking

CONCLUSION:

• First trimester alcohol exposure increases the risk of spontaneous abortion
  • Each successive week of exposure increases the risk of miscarriage
  • The risk is significant even with low levels of alcohol consumption
• The authors conclude

Because home pregnancy testing reliably detects pregnancy as early as 4 weeks’ gestation and alcohol use in weeks 5 through 10 is most concerning for risk, there is a window of opportunity

Therefore, efforts to promote early pregnancy recognition and cessation of alcohol use are warranted to curtail risk of spontaneous abortion

Learn More – Primary Sources:

Week-by-week alcohol consumption in early pregnancy and spontaneous abortion risk: a prospective cohort study

Related ObG Topics:

Safe Passage Study: What is the Risk of Combined Alcohol and Cigarette Exposure During Pregnancy for SIDS?

Does Alcohol Consumption Increase Risk for Preterm Delivery?

Safe Passage Study: Prenatal Alcohol Exposure and Cognitive Abilities at 4 years of Age