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Your Pregnancy Matters

Drinking while pregnant: What we know and what we don’t

Your Pregnancy Matters

A group of friends raising their glasses in a toast at an outdoor gathering.
Will an occasional drink during pregnancy harm a baby? While we’ve long known that heavy alcohol consumption during pregnancy can cause these problems, the effects of an occasional glass of wine is less understood.

“It’s our anniversary Saturday. Would it be OK to have a glass of wine?” “Can I have an occasional beer with dinner?” “I just found out I’m pregnant – but I had a couple drinks last weekend. Is my baby going to be OK?”

Pregnant women often have questions like these. Unfortunately, the advice they get can be confusing. Almost all national health organizations recommend complete abstinence when it comes to drinking during pregnancy, while some obstetricians – including myself – say it’s OK to have a drink now and then.

Still, we can’t ignore the potentially devastating effects of fetal alcohol spectrum disorders (FASDs): low birthweight, developmental delays, behavioral problems, and health problems such as seizures and visual or hearing impairment. Statistics show that as many as 2-5% of children born in Texas may have an FASD, and a 2017 study suggests that number is most likely underreported.

While we’ve long known that heavy alcohol consumption during pregnancy can cause these problems, the effects of an occasional glass of wine is less understood. Because we’re just not sure, there has been a push for women to refrain from consuming any alcohol while trying to get pregnant and during pregnancy.

Pregnancy, drinking, and the COVID-19 pandemic

During the pandemic, people in the U.S. purchased markedly higher amounts of alcohol. A report out of Columbia University found that Americans bought nearly $42 billion worth of alcohol from March to September 2020 – an increase of 20% compared to the same seven months in 2019.

The CDC reports that there was no change in the number of pregnant patients who report drinking from 2019 (pre-pandemic) to 2020 (the first year of pandemic). In both years, approximately 14-15% of pregnant women reported consuming alcohol and 6% reported binge drinking.

A report from Canada describes similar results, but a smaller percentage (6.7%) of women consuming alcohol in pregnancy. However, they also observed an increased rate of cannabis and tobacco use, as well as increased depressive symptoms and financial difficulties in patients who consumed cannabis or tobacco during pregnancy.

While it is good to know that women did not use alcohol to deal with the stress of pandemic, the number of people consuming alcohol during pregnancy is concerning. And, with the national uptick in drinking, patients may have more questions about alcohol use and overuse before, during, and after pregnancy.

What studies say about drinking while pregnant

The research is conclusive: Binge drinking and heavy consumption of alcohol in pregnancy pose a definite risk to the developing fetus. The CDC defines binge drinking as four drinks or more in two hours for women (five drinks or more for men). However, we just don’t have the same level of conclusive information when talking about low-level alcohol consumption.

A woman sitting by a window at night, holding a glass of wine and looking at her smartphone.
Broader studies are needed to investigate the effects of low and moderate alcohol consumption during pregnancy.

For example, a 2012 Danish study examined the effects on 5-year-olds whose mothers drank alcohol during pregnancy, categorized as follows:

  • Low consumption: One to four drinks a week
  • Moderate consumption: Five to eight drinks a week
  • High consumption: Nine or more a week
  • Binge drinking: Five or more drinks during a single occasion

Researchers who knew nothing about the maternal consumption of alcohol during the pregnancy examined the 5-year-old children of those pregnancies. They performed tests on IQ, attention span, and executive functions such as planning, organization, and self-control. They were unable to tell any difference between children whose mothers drank low to moderate amounts of alcohol and those who abstained completely during pregnancy.

While this would seem to suggest that low-level alcohol consumption is safe during pregnancy, there are other factors to consider. First, while the study included 1,600 women, that’s still a relatively small sample size. Second, children’s brains are still developing at age 5, and the full effects that alcohol may have had on them may not yet be measurable.

The authors of the study concluded that more large-scale studies are needed to investigate the effects of low and moderate alcohol consumption during pregnancy – and that for now it’s best for pregnant women to avoid alcohol.

National health organizations advise abstaining from alcohol

There have been a number of publicized statements on alcohol use and pregnancy in the past year.

In November 2015, the American Academy of Pediatrics (AAP) published a report that focused on recognizing, diagnosing, and treating FASD. The AAP reaffirmed their recommendation that no amount of alcohol should be consumed during any trimester of pregnancy with a video series in 2019. 

This follows the advice of most health organizations focused on pregnancy, such as the American College of Obstetricians and Gynecologists.

The CDC caused controversy in February 2016 when it published a report intended to raise awareness of the risk of FASD due to drinking before a woman realizes she is pregnant. The report recommended that women who are sexually active and want to get pregnant should avoid alcohol, and women who are sexually active and don’t want to get pregnant should use an effective birth control method. The report noted that half of pregnancies are unplanned, and even for women trying to conceive, most won’t know they’re pregnant until four to six weeks into the pregnancy.

In a press release announcing the report, a CDC official was quoted as saying: “It is critical for healthcare providers to assess a woman’s drinking habits during routine medical visits; advise her not to drink at all if she is pregnant, trying to get pregnant or sexually active and not using birth control; and recommend services if she needs help to stop drinking.”

In January 2022, the CDC released a Frequently Asked Questions article about alcohol use and pregnancy, reaffirming that, “The best advice is to avoid any alcohol use when you start trying to get pregnant.”

Managing risks while preserving rights

Some pregnant women tell me they feel judged when they have a drink. I am not sure how we got to the point that in May 2016, New York City had to clarify guidelines prohibiting bars and restaurants from refusing to serve alcohol to pregnant women. The guidelines – which also apply to selling and serving foods such as soft cheeses and raw fish – are intended to discourage discrimination against pregnant women.

I understand the messages can seem mixed. For example, venues in New York City that serve alcohol are required by law to post a sign warning of the dangers that alcohol can pose to a developing fetus, but employees of that bar or restaurant must serve pregnant women alcohol if they order it.

Obviously, this is a complex issue. The debate that the New York City guidelines renewed over the risks of drinking while pregnant and preserving a woman’s right to make her own decisions followed the backlash a few months before to the CDC recommendation that women avoid drinking unless they were using birth control. Some women felt that the CDC was being condescending and interfering in their right to make decisions about how they live their lives.

Having a drink during pregnancy is a personal decision

We know drinking heavily during pregnancy is not safe for the baby. We are less sure about the risks of low to moderate drinking, and until we have better information, it’s understandable that health organizations and providers would advise complete abstinence from alcohol.

Women make decisions about risks and outcomes for our health and the health of our children all the time. We decide what contraception to use based on our acceptance of the risk of an unintended pregnancy. We weigh risks and benefits of using anti-nausea medications or other drugs during pregnancy.

Healthcare providers must educate women about what we know regarding alcohol consumption during pregnancy. Women must be allowed to make their own decisions based on the amount of risk they are willing to accept. Many will say, “If there is any risk, I will follow the guidelines and not drink at all.” Others may examine the risks and choose to have an occasional drink.

The trouble with guidelines that recommend total abstinence is they don’t involve nuance. There are certainly women who truly have a problem with alcohol and whose drinking puts their babies at risk. We need to identify those women early and get them help. For women who do not have an unhealthy relationship with alcohol and who want to have a drink on a special occasion, they shouldn’t fear being judged or have others make that decision for them. However, pregnant patients who choose to drink should understand that any alcohol consumption – not just binge drinking – increases specific risks during pregnancy.

Proven risks of any alcohol consumption in pregnancy

Two studies from 2021 support the idea that alcohol consumption during pregnancy isn’t a good idea – both for the overall outcome of the pregnancy and for fetal neurodevelopment.

Increased risk of miscarriage is associated with any alcohol use in the first trimester. A study published in January 2021, which recruited patients prior to becoming pregnant and patients up to 7 weeks of pregnancy, showed an 8% increased risk of pregnancy loss each week between 5 and 10 weeks of gestation in patients who consumed alcohol compared to those who abstained.

To reduce the risk of miscarriage, women who are trying to conceive should consider avoiding alcohol. For those unwilling to do that or those with an unplanned pregnancy, stopping drinking as soon as a pregnancy test is positive may improve the likelihood of successful outcomes.

Stillbirth and fetal growth restriction also are associated with prenatal alcohol exposure. Results from a December 2021 study suggest that alcohol consumption in pregnancy leads to smaller placentas with abnormal blood vessels and abnormal function on the molecular level.

What if I drank before I realized I was pregnant?

Women frequently come to us worried because they had a few drinks before they noticed a missed period. I assure them there is little evidence to suggest that they harmed their pregnancy.

And I emphasize that stopping now that they’ve found out they’re pregnant can still improve pregnancy and fetal outcomes.

I also use this opportunity to discuss how much they normally drink and to educate them about the risks of drinking during pregnancy. If they don’t want to stop drinking entirely, we discuss what might be a reasonable limit. I tell patients I think one to two drinks a week is unlikely to be harmful – but that I can’t guarantee that there are no possible risks. Most of the time, patients just want to know it’s OK to have a glass of wine to celebrate a special occasion.

If you have a problem with alcohol, don’t be ashamed to ask for help. Addiction is a disease, and most people can’t manage it on their own. Your doctor can refer you to a therapist or program that may be able to help. We are here to help you, and we will not judge you. The sooner you get help, the better life will be for you and your baby.

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