Alcohol
Alcohol is a known teratogen and its consumption has been reported to decrease fertility and increase the risk of miscarriage, although the level associated with risk is unclear. Alcohol consumption at extreme levels is known to be dangerous to the unborn child, but the effect at lower levels is less certain. However, levels as low as one drink per week have also been associated with reduced conception rates . The most vulnerable time for the unborn child is the first few weeks after conception, when often the pregnancy has not yet been detected.
WHO findings have established that small to moderate doses of alcohol during pregnancy may have an impact on children’s cognitive and socio-emotional development.
In men, alcohol consumption has been linked to testicular atrophy, decreased libido and decreased sperm count, volume and quality .
In women, amounts of alcohol ranging from one drink a week to five units per day can have various effects including anovulation, luteal phase dysfunction, delayed conception, abnormal blastocyst formation, risk of spontaneous abortion and foetal death.
Current evidence is inconclusive regarding what dose of alcohol may be safe to consume prior to and during pregnancy, making it difficult to predict the risk . With this understanding, the safest measure to take is to avoid all alcohol during, or when planning, a pregnancy.