08/09/2017 03:58 SAST | Updated 08/09/2017 03:58 SAST

Severe Adverse Effects Of Excessive Alcohol During Pregnancy Are Not Limited To Fetal Alcohol Syndrome

Recent research indicated that the severe effects of smoking are enhanced by the use of alcohol and also the other way around.

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'Fetal alcohol spectrum disorders' is the summary term to describe physical and neurobehavioural problems in children exposed to alcohol in utero. It consists of fetal alcohol syndrome (FAS), partial FAS, alcohol-related birth defects and alcohol-related neurological disorders.

However, there are also other severe effects of alcohol on pregnancy outcome such as fetal growth restriction, preterm birth and possibly also stillbirth. Cigarette smoking is also strongly associated with these three common complications. Recent research indicated that these severe effects of smoking are enhanced by the use of alcohol and also the other way around.

Placental abruption is another severe complication of pregnancy. It is the main cause of stillbirth in the Western Cape and also in many other populations, including high-income countries. Smoking is a well-known risk factor for placental abruption, but it now seems that the use of alcohol increases this risk.

Preterm birth and fetal growth restriction could have permanent effects on future health as these conditions are associated with hypertension, diabetes and coronary heart disease. The severe adverse effects of excessive alcohol during pregnancy is therefore not limited to FAS only.

Reduced growth features such as height, weight and head circumference in combination with the facial features of short palpebral fissures [indicating a smaller eye], smooth and long upper lip and thin upper lip are used for diagnosis of FAS and partial FAS. Congenital organ defects include cardiac and renal anomalies.

High-risk pregnant women populations included the American Indians in the United States and the Coloured women in Cape Town.

Intellectual function is variable among the spectrum, with a wide IQ range of 20 to 100 in the literature. The average IQ of a child with FAS seems to be 70, but their functioning seems to be well below their intellectual potential.

The Safe Passage Study, conducted by the Prenatal Alcohol in Sudden Infant Death Syndrome (SIDS) and Stillbirth (PASS) Network investigated the role of prenatal drinking, modified by prenatal smoking, on poor peri- and postnatal outcomes, particularly SIDS and stillbirth, in populations at high risk for drinking and smoking during pregnancy.

More than 12,000 pregnancies were examined and infants were followed up until the age of one year. The high-risk pregnant women populations included Native Americans in the US and coloured women in Cape Town, South Africa.

Prenatal alcohol exposure and cigarette smoke information was collected carefully up to four times during pregnancy. Binge drinking was defined as four or more drinks per occasion. Heavy smoking was defined as 10 or more cigarettes per day.

For the 11,692 pregnancies, drinking and smoking exposure information was successfully obtained at nearly 100 percent of eligible prenatal visits. Women reported drinking during pregnancy in 61.2 percent of the 11,692 pregnancies, smoking in 56.3 percent and dual exposure in 37.4 percent. The proportion of pregnancies exposed, as well as the quantity of exposure, decreased over the course of pregnancy.

The combination of smoking and drinking is more harmful in pregnancy than smoking or drinking only.

In the third trimester of pregnancy, 15.3 percent of women still reported drinking (6.1% binged), 40.0 percent reported smoking (6.1 percent smoked ≥ 10 cigarettes/day) and 11.2 percent reported both (1.1 percent binged and smoked ≥ 10 cigarettes/day). Continuous drinkers were more likely to smoke and to smoke higher quantities.

Restricting the sample to women who enrolled exactly twice with singleton pregnancies for both (n=1,345), 26.3 percent increased drinking, 22.8 percent decreased drinking and 50.9 percent did not change drinking patterns or trajectory group assignment in the second pregnancy as compared to the first. Of these 1,345 women, 17.0 percent increased, 14.0 percent decreased and 69.0 percent remained unchanged with respect to smoking trajectories in the second as compared to the first.

The prevalence rate of FAS in certain communities is in South Africa is high. Some of these communities are remote from wine producing areas. In addition, the drink most commonly consumed is beer and not wine.

The high level of drinking and smoking we exposed in the Safe Passage Study is of great concern. It is disappointing that many pregnant women do not quit smoking and drinking during pregnancy, in spite of regular warnings about the harmful effects. The combination of smoking and drinking is more harmful in pregnancy than smoking or drinking only.