Presumptive Advice Ignores Science on Salutary Effects of Moderate Consumption and May Yield Unintended Consequences

On February 2, 2016, the Centers for Disease Control issued a new pronouncement through its published CDC Vital Signs advising women of child-rearing age to avoid any consumption of alcohol unless they are on birth control.  The CDC addressed its guidance to all women between the ages of 15 and 44, with a focus on the 3.3 million women that the agency estimates are at risk of exposing a developing baby to alcohol because they are drinking, sexually active, and not using birth control to prevent pregnancy.  The CDC’s press release announcing this guidance is accessible online at:    

Focusing on the risk of alcohol-imperiled pregnancies, the CDC defined a woman considered to be at risk for an alcohol-exposed pregnancy “if in the past month she was not sterile, her partner was not known to be sterile, she had vaginal sex with a male, drank any alcohol, and did not use birth control.”  The CDC’s press release announcing the guidance also included a statement from Coleen Boyle, Ph.D., director of CDC’s National Center on Birth Defects and Developmental Disabilities, declaring that:

“Every woman who is pregnant or trying to get pregnant – and her partner – want a healthy baby. But they may not be aware that drinking any alcohol at any stage of pregnancy can cause a range of disabilities for their child,”1

Why the agency felt compelled to issue this guidance is unclear.  However, given the breath of the targeted population (women aged 15 - 44 not using birth control), as well as the current state of scientific research on the subject of pregnancy and alcohol consumption, knowledgeable observers reasonably can question whether the authors of this recent guidance either are: (i) well-intention but extremely naïve (and perhaps not fully informed for the reasons explained below), or (ii) just plain Prohibitionist in their true objectives. 

As for being fully informed, the CDC’s new guidance ignores without comment or any reference numerous scientific studies indicating that carefully limited, moderate consumption of alcohol may not produce negative effects on a pregnancy, and may yield positive effects for the mother (such as stress-reduction).  Public coverage of these studies goes back several years.  Examples include:

ARTICLE:  Holohan, Meghan, “New study shows no harm from moderate drinking in pregnancy, but experts urge caution,” TODAY Parents (January 3, 2014); this article is accessible online at:

CITED RESEARCH: Janni Niclasen, “Drinking or Not Drinking in Pregnancy: The Multiplicity of Confounding Influences,” Alcohol and Alcoholism, vol. 49, no. 3 (2014) DOI: (Studies investigating associations between prenatal exposure to low-moderate doses of alcohol and mental health development in childhood are inconsistent. The aim of the present study was to compare women who drink and who do not drink alcohol in pregnancy on a number of potential confounding variables, and to investigate whether any latent variables could be identified among these.  Conclusions are that some scientific alcohol-pregnancy studies have reported a J-shaped (i.e. curvilinear) function, suggesting that exposure to moderate amounts of alcohol do not present negative affects, and apparently can act as a protective factor for the developing fetus).  The text of this published study is accessible online through the Journals Website of the Oxford University Press at

ARTICLE:  Szalavitz, Maia, “Light to Moderate Drinking in Pregnancy May Be Safe, Study Says,” Time Magazine (June 20, 2012); this article is accessible online at:

CITED RESEARCH: “Danish studies suggest low and moderate drinking in early pregnancy has no adverse effects on children aged five,” BJOG: An International Journal of Obstetrics and Gynecology (BJOG) (published on June 20, 2012) (referencing the following five scientific papers which, ironically, were “supported primarily by the Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA.”).

  • Paper 1:   Kesmodel U, Bertrand J, Støvring H, Skarpness B, Denny C, Mortensen E, “The Lifestyle During Pregnancy Study Group: The effect of different alcohol drinking patterns in early to mid-pregnancy on the child’s intelligence, attention, and executive function,” BJOG (2012); DOI: 10.1111/j.1471-0528.2012.03393.x.
  • Paper 2:   Falgreen Eriksen H, Mortensen E, Kilburn T, Underbjerg M, Bertrand J, Støvring H, Wimberley T, Grove J, Kesmodel U, “The effects of low to moderate prenatal alcohol exposure in early pregnancy on IQ in 5-year-old children,” BJOG (2012); DOI: 10.1111/j.1471-0528.2012.03394.x.
  • Paper 3:   Kesmodel U, Falgreen Eriksen H, Underbjerg M, Kilburn T, Støvring H, Wimberley T, Mortensen E., “The effect of alcohol binge drinking in early pregnancy on general intelligence in children.” BJOG (2012); DOI: 10.1111/j.1471-0528.2012.03395.x.
  • Paper 4:   Underbjerg M, Kesmodel U, Landrø N, Bakketeig L, Grove J, Wimberley T, Kilburn T, Sværke C, Thorsen P, Mortensen E., “The effects of low to moderate alcohol consumption and binge drinking in early pregnancy on selective and sustained attention in 5-year-old children,” BJOG (2012); DOI: 10.1111/j.1471-0528.2012.03396.x.
  • Paper 5:   Skogerbø A, Kesmodel U, Wimberley T, Støvring H, Bertrand J, Landrø N, Mortensen E., “The effects of low to moderate alcohol consumption and binge drinking in early pregnancy on executive function in 5-year-old children,” BJOG (2012); DOI 10.1111/j.1471-0528.2012.03397.x.

ARTICLE:  Sohn, Emily, “Light Drinking Said OK for Pregnant Women,” Discovery News Online (October 6, 2010); this article is accessible online at:

CITED RESEARCH:  Yvonne J Kelly, Amanda Sacker, Ron Gray, John Kelly, Dieter Wolke, Jenny Head, Maria A Quigley, “Light drinking during pregnancy: still no increased risk for socioemotional difficulties or cognitive deficits at 5 years of age?” Journal of Epidemiology Community Health (Accepted for publication on June 25, 2010; published online October 5, 2010) (This study examines the relationship between light drinking during pregnancy and the risk of socioemotional problems and cognitive deficits at age 5 years; Conclusions are at age 5 years cohort members born to mothers who drank up to 1–2 drinks per week or per occasion during pregnancy were not at increased risk of clinically relevant behavioral difficulties or cognitive deficits compared with children of mothers in the not-in-pregnancy group). The full text of this published study is accessible online at:

As if this research itself is not enough to cause reconsideration of the CDC’s latest pronouncement, a recent blog post draws a timely connection between wine-based studies and consideration of craft beer consumption by women during pregnancy. See  Rasanen, Vanessa, “Pregnant Women Should Treat Craft Beer Like Wine: Some doctors and midwives still recommend wine for pregnant women, while giving craft beer the cold shoulder,” The Federalist (Online) (posted January 8, 2016) and accessible at: (informative blog post equating wine and beer consumption for pregnant women).

There is no debate that the consumption of any alcohol by pregnant women is a serious issue, meriting careful consideration by every woman who is pregnant or contemplating pregnancy.  Individual physiology has a lot to do with any recommendation on alcohol consumption or abstention.  Some women (as well as men) have a high tolerance for alcohol and can benefit from carefully limited, moderate consumption; others have a physiology that affords very little tolerance, and should abstain from alcohol altogether.  The literature, including a number of the studies cited above, affirm this point.

The challenge presented by the CDC’s recent recommendation is that if the government tells all women between the ages of 15 and 44 that they should not consume any alcohol beverage unless they are on birth control, it could prove counter-productive in a number of ways.  Despite the best of intentions, the presumptive guidance offered by CDC is extreme to a point that calls into question its efficacy. 

Scientific American actually hit the nail on the head in a 2013 article on the subject of alcohol consumption during pregnancy.  An excerpt from that article, entitled “How Much Alcohol Is Safe for Expectant Mothers? An occasional drink during pregnancy is unlikely to harm most children, but we lack the tools to fully measure alcohol's effects on the developing brain,” states:

Nobody questions the notion that heavy drinking during pregnancy is harmful. It can cause facial abnormalities, central nervous system problems and stunted growth. But evidence regarding the effects of light or occasional drinking is mixed. In five epidemiological studies published in 2012, medical psychologist Erik Mortensen of the University of Copenhagen and his colleagues found that five-year-old children born to women who had one to four drinks a week during pregnancy displayed no deficits in general intelligence, attention or other types of higher-order thinking. On the other hand, in 2011 psychiatrist Nancy Day of the University of Pittsburgh and her colleagues reported that teens born to women who averaged more than one drink a week during pregnancy were twice as likely as those born to nondrinkers to have conduct disorder, a condition characterized by theft, deceit or violence.

The truth is hard to discern because research on the issue is fraught with problems. The ideal type of experiment is not ethical: scientists cannot randomly assign one group of women to drink during pregnancy and compare the outcome with those instructed to abstain. As a result, they must compare what happens to women who choose to drink during pregnancy with those who do not, and these women often differ in important ways. All things considered, having an occasional drink during those nine months—say, one or two a week—probably poses little, if any, harm. Still, some experts warn, light or sporadic drinking may have effects we do not know how to measure. . .

Because of such findings and all the other uncertainties, policy makers are unlikely to ever give the green light to occasional drinking during pregnancy. “We will never, ever, ever know how much is safe for every individual,” says biologist Kathleen K. Sulik of the University of North Carolina at Chapel Hill. What is harmless for a woman of one race, weight, nutritional status and genetic background may be dangerous for another. That said, the literature is reassuring to the many women who socially drank before realizing they were pregnant and to those who, like me, had one celebratory glass.

The full text of this Scientific American article is accessible at:

Aside from the uncertain scientific underpinnings of the CDC’s expansive advice, additional cause for concern arises from its propensity to produce unintended consequences.  The unforeseen result of the agency’s expansive guidance may be to push more young women (ages 15 – 21) who are determined to drink for social reasons towards birth control.  This might be a salutary outcome in the view of many folks who advocate both greater access to, and use of, safe methods of birth control.  However, it likely will not be warmly received by others, e.g., people of faith whose religion precludes the use of birth control products, concerned parents who feel that premature usage of birth control will lead their daughters to accelerated sexual activity, etc.

Another concern is that the CDC’s recent guidance may increase the risk that women generally, and pregnant mothers in particular, will questioning other, less controversial guidance on alcohol issued by the federal government and similar authorities, because they cannot in their common sense believe one beer during one weekend will affect their unborn child?  Lest it be forgotten: One of the principal lessons of Prohibition was that regulators should avoid taking a position on guiding the public’s behavior that either is unenforceable or just so questionable that it causes the citizenry to lose faith in the integrity or judgment of their government.

A balanced and arguably more credible approach would have been for the CDC to raise its concerns associated with alcohol consumption during pregnancy, and then recommend that women consult with a doctor on these issues.  Presumably the doctor would have a better knowledge of the individual patient s/he is consulting with, and could provide more specific and appropriate advice tailored to that patient.

Advising women to consult their physicians regarding issues relating to pregnancy and alcohol?  Clearly a smart piece of advice.  Telling all women aged 15 – 44 who are capable of conception that they should not drink unless they are on birth control?  Not so clear.