Social Drugs and Pregnancy

The main social and illegal drugs commonly used, which can cause problems in and after pregnancy are:

• Smoking . Carbon monoxide and nicotine in tobacco both reach the baby very easily through the placenta . Both of these can cause problems with the baby's growth and development before birth. Carbon monoxide and Nicotine reduce the amount of oxygen available in the mother's blood, which can affect the development and size of the baby.
  Smoking can cause problems in pregnancy such as miscarriage , stillbirth , placental problems , bleeding during pregnancy and premature birth . Babies practise breathing movements while in the womb. It has been shown that cigarette smoking can disrupt these breathing movements. Research has also shown that babies of smokers are generally below the average birth weight and that these babies can develop complications such as infections and breathing problems during the first weeks of life. Some research has indicated that smoking may increase the risk of cot death . [ 1 ]
• Alcohol crosses the placenta to the baby. It can accumulate in the amniotic fluid surrounding the baby before the birth and cause problems such as miscarriage , stillbirth , bleeding during pregnancy and premature birth . There is evidence to suggest that if a woman drinks two or more standard drinks each day the baby can be affected and grow slowly. If a woman drinks six or more standard drinks each day the baby may have slow physical growth, poor coordination and movement and intellectual disability ( foetal alcohol syndrome ). The World Health Organisation suggests that there is really no safe level of alcohol consumption during pregnancy and that no alcohol at all is the safest approach. Babies of women who are heavily dependent on alcohol can suffer withdrawal after birth. The symptoms can include tremors, irritability, fits and bloated abdomen. [ 1 ]
• Cocaine . Considerable research into the effects of cocaine use in pregnancy indicates that cocaine may cause miscarriage , stillbirth , bleeding , abruptio placentae and premature birth . It also indicates that cocaine use may have an effect on the baby's growth and development before, and even after birth. Cocaine increases the heart rate in both the mother and baby and the supply of oxygen and blood to the baby is reduced, which makes it more likely that the baby will be small and grow slowly. Several cases of bleeding in the brain have been reported in babies whose mothers were dependent on cocaine. A number of foetal abnormalities have been reported concerning the use of cocaine during pregnancy. If cocaine is used close to the birth the baby may be born excessively active and appear distressed and restless. Withdrawal symptoms can occur in the babies of mothers who use cocaine regularly. These symptoms appear similar to those of adults experiencing withdrawal and can include sleepiness and lack of responsiveness. [ 1 ]
• Marijuana . Women who smoke marijuana often smoke it with tobacco and therefore there will be risks to the baby from tobacco smoke. THC ( Tetrahydrocannabinol ) is the active ingredient in marijuana and does cross the placenta. It is stored in the amniotic fluid that the baby lives in prior to birth. It is possible that marijuana use in pregnancy is associated with premature labour and small babies , with all the associated dangers of low birth weight including infections and breathing problems. [ 1 ]
• Caffeine . A stimulant found in colas, coffee, tea, soft candies, chocolate, cocoa, and over-the-counter and prescription drugs, caffeine has been a controversial topic in pregnancy nutrition for more than a decade. A 1980 study by FDA found that caffeine, when fed to pregnant rats, caused birth defects and delayed skeletal development in their offspring. At that time, although the human implications were unknown, FDA advised pregnant women to eliminate caffeine from their diets.
  Since then, more studies have been done to determine the effects of caffeine on the fetus. A study of women in Costa Rica, where coffee consumption is high, showed a significantly lower birth weight for infants and a lower concentration of iron in mothers who were coffee drinkers. This report indicated that maternal coffee intake may also contribute to maternal and infant anaemia . [ 2 ]

The information in this page is presented in summarised form and has been taken from the following source(s):
1. Australian Drug Foundation, Alcohol, Other Drugs and pregnancy: http://www.adf.org.au/adp/
2. The National Women's Health Information Center (NWHIC) FAQs: http://www.4woman.gov/faq/