Alcohol is widely consumed by adults worldwide in spite of its harmful effects on health. This blog describes the effect of alcohol on female and male fertility and also on the growing fetus during pregnancy.
Effect of alcohol on female fertility
It is quite unknown how exactly how alcohol affects fertility in female, but has been shown in various studies that women who drink alcohol take longer time to conceive.
Alcohol reduces ovarian reserve, especially for those who do binge drinking.
Quite a few studies have shown that alcohol consumption cause rise in the oestrogen level, which in turn can cause problems with ovulation and hence infertility.
Alcohol reduces ovarian reserve and can cause ovulatory problems.
Can alcohol cause infertility in a man?
Alcohol can affect sperm:
Alcohol consumption has an effect on spermatogenesis (sperm production). With continued alcohol intake, the first change seen is the changes in the shape of the sperm (teratozoospermia), followed by drop in the number and motility of sperm (oligoasthenozoospermia) and then complete absence of sperm (azoospermia), according to a 6-year follow up study.
Alcohol can cause DNA damage in the sperm:
Alcohol consumption in itself can increase the rate of DNA damage in the sperm. So even if the count and motility or morphology of the sperm are normal, they might not be functioning optimally in presence of DNA damage.
Alcohol can lower sexual function:
Chronic alcohol use can cause liver dysfunction, which in turn can lead to defective metabolism of oestrogen in men and lower the testosterone level, causing sexual dysfunction, difficulties in arousal, erection and also ejaculation.
Maternal alcohol consumption can lower sperm count in the male fetus:
Maternal alcohol intake during pregnancy has deleterious effect on sperm parameters of male offspring. Study have shown that men whose mothers consumed >4-5 units of alcohol per week during pregnancy had 32% lower sperm count than men whose mothers drank <1 unit of alcohol per week during pregnancy.
Alcohol can kill sperm and cause sexual dysfunction in men.
Mother's alcohol intake during pregnancy can cause sperm problem in the male foetus.
Effect of alcohol on IVF
Alcohol intake also lowers the chances of success of IVF treatment.
Alcohol lowers the success of IVF
Effect of alcohol on pregnancy and breastfeeding
Alcohol easily crosses placenta and reaches the developing foetus. The liver of foetus is not mature enough to break down alcohol. Hence your foetus and will end up having higher levels of alcohol than you are drinking.
Increased risk of miscarriage:
Alcohol can cause miscarriage in early pregnancy. The risk of miscarriage is almost doubled if the woman drinks 4 or more units of alcohol per week, according to a study.
Increased risk of low birth weight and preterm birth:
Moderate to heavy alcohol intake, including binge drinking has been found to increase the risk of low birth weight babies and preterm labour.
Increased risk of stillbirth:
With five or more units of alcohol per week there is increased risk of stillbirth.
Increased risk of Fetal alcohol syndrome:
All the different organs are developed in the foetus in first 3 months of pregnancy. Hence alcohol consumption during early pregnancy can affect baby’s development. It can cause Fetal Alcohol Spectrum Disorder (FASD), characterised by facial abnormalities, growth deficiency and delayed development of nervous system of the baby. It can also cause alcohol-related neurodevelopmental disorder (ARND) and alcohol-related birth defects.
Alcohol increases risk of miscarriage, preterm and stillbirth and developmental defects in the baby.
Alcohol can pass through breast milk. It can affect baby’s development, sleep pattern. Hence it would be advisable to avoid if you are breastfeeding.
How much alcohol can I take when I am trying for pregnancy?
The recommended alcohol intake for women trying to conceive is no more than 1-2 units once or twice per week as per the NICE guideline.
The recommended allowance for men trying for pregnancy is no more than 3-4 units of alcohol per day as per the NICE guideline.
However, the effect of alcohol will depend on various factors like age, weight, metabolism, and food taken along with alcohol and also any existing medical conditions and medicines.
Taking into account the wider implication of alcohol on health, including cancer risk, there is no safe limit and it is better to avoid alcohol completely.
The UK Department of Health has also published a guideline on alcohol intake, where four UK Chief Medical Officers have confirmed that there is no safe level of alcohol intake.
There are no safe limits of alcohol
What is an unit of alcohol?
1 unit of alcohol is 10 mls or 8 gms of pure alcohol, which your body takes one hour to break down.
The number of unit would depend on the size of the drink and also on the alcohol strength, (which would be written on the alcohol bottle as alcohol volume or ABV and expressed as %).
It can be calculated as:
amount of the drink (ml) x alcohol strength (%, written on the bottle) ÷1000
A rough guide is as follows:
Small glass of spirit (25 mls) (Vodka, gin, baijiu, tequila, rum, whisky, brandy, singani and soju) with 40% alcohol – 1 unit
Small glass of red/white/rose wine (125 mls) with 12% alcohol- 1.5 units.
Standard glass of red/white/rose wine (175 mls) with 12% alcohol - 2.1 unit
Bottle of beer/lager/cider (330 mls) with 5% alcohol- 1.7 units
1unit of alcohol is 10 mls of pure alcohol. It depends of size of the drink and its alcohol strength.
Is alcohol effect reversible?
The good news is that the effect of alcohol is not permanent.
The sperm production takes 3 months. Hence fast and drastic improvement in semen parameters can be seen within 3 months of abstinence. This has been shown in a follow up study.
Effects of alcohol in pregnancy are 100% preventable if alcohol is avoided completely. There are no safe limits of alcohol in pregnancy.
By the time the woman known that she is pregnant, the development of vital organs of the foetus has already started. Hence it is advisable to avoid alcohol pre-pregnancy.
Baby’s brain keeps growing throughout the pregnancy. Hence it would be advisable to stop anytime during pregnancy, sooner the better.
Alcohol effects are reversible
Where to seek help if you wish to cut down or stop drinking?
It can be sometimes quite difficult to stop suddenly. If you are thinking of cutting down or giving up alcohol, you have got the awareness and already taken the first step.
First of all you should talk to your midwife or doctor. There are various charities, which are there to help.
Written by Dr Anupa Nandi