Taking street drugs is inadvisable when pregnant because it exposes you and your baby to a range of hazards. You also risk contracting the HIV virus if you inject drugs with shared needles.
Cause low birth weight.
Causes premature labour. There is a possible risk of chromosomal abnormality.
Causes miscarriage, premature labour, stillbirth, serious placental bleeding, low birth weight baby and increased risk of Sudden Infant Death Syndrome.
Apart from the possible effects on you, such as dehydration and personality changes, taking ecstasy may increase the risk of serious bleeding from the placenta.
Heroin and Methadone
Causes low birth weight, premature labour, higher rate of twins. After delivery, baby suffers withdrawal symptoms, higher risk of fits, increased risk of cot death (sudden infant death syndrome - SIDS).
Causes birth defects.
Even if you take marijuana infrequently throughout pregnancy, you risk gaining insufficient weight and hence delivering a low-birthweight baby, severe vomiting, complicated labour and causing distress to the baby.