Alcohol, nicotine and cannabis when trying for a baby, during pregnancy and while breastfeeding

Three stages with different questions

Perhaps you are a sperm donor wanting to improve your results. Perhaps you have just had a positive pregnancy test and are thinking about last weekend. Or you may be breastfeeding and wondering what could still pass into your milk after using a substance. These situations are related, but the same rule cannot answer all three.

Before pregnancy

This stage concerns fertility, sperm, hormones and sexual function, as well as a pregnancy that might already have started. The person hoping to become pregnant and your shared surroundings also need to be included in the planning.

During pregnancy

Some substances can reach the baby through the placenta. The health of the pregnant person, the supply of nutrients and oxygen through the placenta, and additional exposure to smoke also matter.

During breastfeeding

The concerns are substances in breast milk, smoke in the environment and safe care of the baby. How quickly a substance leaves the body and which feeding arrangement is appropriate depend on the substance.

A finding about the future father's drinking therefore cannot establish that alcohol is safe in pregnancy. Equally, one evening before conception cannot provide a reliable prediction of a child's health.

What substance use can tell us about sperm and fertility

Sperm are produced and mature over several weeks. A semen analysis therefore does not simply reveal whether yesterday was a healthy day. Fever, the period without ejaculation before the sample, incomplete collection and variation between tests can affect the findings. Sleep, illness and your longer-term circumstances should also be discussed.

Normal results are not an all-round certificate of health. The reference values in the WHO laboratory manual do not create a clear dividing line between fertile and infertile. When findings are abnormal, a clinician's assessment determines whether and when a repeat test is needed.

For research into substance use, it matters what was measured: sperm count and movement are different outcomes from pregnancy or live birth. Other substances, illnesses and accompanying factors can influence the associations. Improved semen results therefore do not guarantee a pregnancy.

Alcohol in men: consider both quantity and drinking pattern

Sustained heavy alcohol use is particularly relevant to male fertility. It can be associated with altered hormone regulation and testicular function. Findings for small or occasional amounts are less conclusive. Saying that a single beer destroys sperm would be as misleading as giving blanket reassurance about regular binge drinking.

Drinking can also make trying for a baby harder in practical ways, for example through its effects on sleep, sex drive, erections or keeping agreed appointments. A review of lifestyle and male fertility discusses these hormonal, sexual and reproductive links.

At a medical appointment, the actual pattern helps more than describing drinking as occasional: on how many days, roughly how much, and whether intoxication happens repeatedly. If you want to reduce drinking substantially, plan a period of several weeks and observe how daily life and symptoms change. Where dependence is involved, this step requires medical support.

Smoking, nicotine and fertility

There is evidence linking cigarette smoke to poorer sperm count, movement and shape, as well as damage to sperm DNA. This does not mean every man who smokes is infertile. Stopping smoking is nevertheless a useful starting point for reducing avoidable exposures.

Tobacco smoke should not be equated with nicotine. Cigarettes also expose you to carbon monoxide and many products of combustion. There is less evidence about vapes and nicotine pouches in relation to human fertility; the absence of long-term data is not proof that they are harmless. The ASRM statement on tobacco, nicotine and cannabis explains these differences.

Smoking matters for the person who wants to become pregnant too: in women, tobacco use is associated with reduced fertility and poorer outcomes from fertility treatment. Stopping smoking is therefore relevant to both people, including in private sperm donation. Smoke-free surroundings also reduce exposure to passive smoke.

Cannabis when trying for a baby: evidence without simple limits

Research into cannabis and male fertility is inconsistent. Some studies find changes in semen parameters or hormones, while others find no clear association with the time it takes to conceive. THC concentration, frequency, method of use and accompanying tobacco use vary considerably. ASRM therefore assesses these links more cautiously than the established risks of smoking.

When you are actively trying for a baby or have abnormal results, it is sensible to discuss cannabis openly and plan to stop using it. This reduces a possible exposure without promising that everything will be normal after a particular number of days without use. If cannabis is mainly used for getting to sleep or managing anxiety, the plan needs appropriate help for these symptoms as well.

Anyone who could become pregnant should not rely solely on studies of sperm. Advice to avoid cannabis in a possible early pregnancy applies before a positive test too.

Testosterone and anabolic steroids need a separate assessment

Testosterone supplied from outside the body can suppress the hormonal signals that the testes need for sperm production. Sperm numbers may fall markedly or production may stop altogether. More muscle, a stronger sex drive or a high testosterone level therefore does not necessarily mean greater fertility.

The AUA/ASRM guideline on male infertility advises against testosterone on its own for people who want children now or in the future. This concerns prescribed treatment as well as steroid cycles and self-medication for gym or fitness purposes.

Discuss the preparation, dose and duration with a urologist or andrologist. Recovery may take months and sometimes longer; there is no fixed recovery deadline. Do not stop prescribed treatment yourself or attempt to restart sperm production using your own combinations of hormone products.

Opioids, cocaine and other substances

The subject of drugs and sperm extends beyond cannabis. Opioids can affect the hormonal system and consequently libido and sexual function. Cocaine and other stimulants also carry substantial risks for the heart, circulation and mental health. Research cannot provide a reliable ranking of doses that are safe for conception.

Prescribed pain relief or treatment for opioid dependence differs from uncontrolled use. For opioid dependence in pregnancy, methadone or buprenorphine may be part of recommended treatment. Do not stop without medical advice: the CDC guidance on opioid dependence during pregnancy highlights the benefit of coordinated care. Newborn babies may develop withdrawal symptoms following opioid exposure, so the birth team should know early. This risk is not a reason to leave out necessary treatment.

Severe drowsiness, slowed breathing, chest pain, seizures or loss of consciousness require urgent medical care. These symptoms should not wait until the next fertility appointment.

Understanding sugar and using substances together

Sugar does not fall into the same risk category as tobacco smoke or anabolic steroids. Having a dessert does not suddenly make sperm unusable. A consistently very energy-dense diet can affect weight and metabolism; that is a different issue from a direct drug effect. Significant tiredness or loss of libido should not therefore be attributed to sugar alone without further consideration.

Using several substances together is directly relevant, however. Alcohol, tobacco and cannabis can overlap in everyday life and make abnormal findings harder to explain. Combining alcohol with opioids or sedating medicines such as benzodiazepines is especially dangerous: their depressant effects can reinforce each other and impair breathing. This is covered in the FDA warning about opioids and sedating substances.

Record medicines too, along with the reasons for taking them, such as poor sleep or anxiety. Help to stop using substances should go hand in hand with treatment of these symptoms. Supplements cannot cancel out the effects of substance use or replace that treatment; read the guide to supplements when trying for a baby.

Alcohol in pregnancy: no proven safe threshold

Alcohol can pass through the placenta to the embryo or foetus. No safe amount, safe stage or safe type of alcoholic drink has been established during pregnancy. The recommendation is therefore to avoid alcohol throughout pregnancy. This also applies if you are trying for a baby and pregnancy is already possible. The CDC information on alcohol in pregnancy explains the advice.

A safe limit cannot be established by experimenting on pregnant people. Research therefore depends mainly on observational studies, in which quantities and accompanying factors are not always fully recorded.

Drinking a lot within a short time produces high alcohol levels in the blood. Binge drinking is particularly concerning, but repeated smaller amounts are not automatically safe either. Beer, wine, sparkling wine and spirits differ in their alcohol content, not in whether that alcohol can reach the baby.

Organs begin to form in the early weeks, whereas the brain continues developing throughout pregnancy. There is no later stage from which drinking is reliably harmless. At the same time, previous exposure does not mean damage has definitely occurred.

FASD and other possible consequences of alcohol

Fetal alcohol spectrum disorders, or FASD, is the umbrella term for different possible effects of alcohol exposure before birth. Growth, physical development, learning, memory, attention, planning and impulse control may be affected. Difficulties with behaviour and regulating emotions sometimes only become noticeable as everyday demands increase.

Physical features can include a smaller head circumference or problems with growth. Some affected people have characteristic facial features, such as short eye openings, a smooth groove between the nose and upper lip, and a thin upper lip. The absence of these features does not rule out alcohol-related developmental difficulties.

FAS and pFAS

Fetal alcohol syndrome and partial fetal alcohol syndrome are diagnostic terms within this spectrum.

ARND and ARBD

These terms refer to alcohol-related neurodevelopmental disorders and alcohol-related birth defects respectively. The diagnostic categories used vary between guidelines.

The CDC overview of FASD explains this terminology. For diagnosis in Germany, the AWMF guideline on FASD in children and adolescents is relevant. Diagnosis needs experienced professionals and cannot be based on an amount of alcohol consumed or a single physical feature.

Drinking in pregnancy is also associated with miscarriage, preterm birth and other adverse pregnancy outcomes. A scan without concerning findings is useful, but cannot exclude every later learning or developmental effect. An adverse outcome likewise does not automatically mean that previous drinking caused it.

Use before a positive test: what to do now

Many pregnancies are not recognised until several weeks have passed. If you drank alcohol, smoked or used cannabis beforehand, the first task is to avoid further exposure and discuss it during antenatal care. An isolated past exposure does not prove permanent harm.

Note the timing, approximate amounts, repeated use or binge drinking, and any other substances involved as honestly as possible. You do not need to reconstruct every millilitre perfectly. These details are there to support advice, rather than start an endless search for a guarantee about the past.

A useful question at the appointment is which checks and support are appropriate now. If alcohol dependence or a history of severe withdrawal is possible, arrange medical help that same day to withdraw safely. This particular situation must not be mistaken for advice to carry on smoking cigarettes.

Smoking in pregnancy and after birth

Several exposures combine when you smoke. Carbon monoxide reduces the blood's ability to carry oxygen; nicotine and other smoke constituents affect the pregnant person's body and the child's development. Established risks include problems with growth, low birth weight and preterm birth. Placental complications are also a risk.

Smoke still matters after birth: among other effects, passive smoke raises infants' risks of sudden infant death syndrome, lower respiratory tract illnesses and middle ear problems. The CDC overview of smoking and maternal and infant health brings these findings together.

It is best to stop before pregnancy. Stopping later is still worthwhile because it prevents further exposure. One cigarette or a relapse does not make your previous smoke-free time worthless. The priority is to become smoke-free again and address what triggered the lapse.

Vapes, shisha, snus and nicotine pouches

The absence of combustion does not automatically mean there is no risk. It would also be inaccurate to describe every product as equally harmful. To make a decision, consider smoke constituents, nicotine, additives and the evidence for each product separately.

E-cigarettes and vapes

These avoid some combustion products from cigarettes, but can deliver nicotine and other substances in their aerosol. They are not an alternative with established safety in pregnancy. Nicotine-free liquids have not been reliably tested as pregnancy-safe products either.

Shisha

Water does not reliably filter out the harmful exposure. Smoke and carbon monoxide remain concerns, and long sessions can involve considerable exposure.

Snus and nicotine pouches

Snus contains tobacco; nicotine pouches may be tobacco-free. Both can deliver nicotine. Being smoke-free does not make them safe options in pregnancy or an equivalent replacement for medically planned support to stop.

The CDC information on the health effects of vaping describes the risks and gaps in knowledge. If you have already moved to another product, discuss a realistic next step. Returning to cigarettes is not the answer. The aim is to be smoke-free and, where possible, nicotine-free, with support you can put into practice.

Passive smoke: keep your home and car smoke-free

Regular smoke in your surroundings matters even if you do not smoke. Risks from passive tobacco smoke during pregnancy and infancy are established. Cannabis smoke is also unsuitable around pregnant people or babies; mixing cannabis with tobacco combines both exposures.

An open window, moving to another corner or briefly airing a room does not make a smoky indoor space reliably protective. Space is particularly limited in a car. A practical rule is therefore no smoking in the home or car, including when the baby is not currently there.

Partners, family and visitors can follow this rule without daily negotiations about exceptions. Further practical advice is available in Kindergesundheit-Info's information on passive smoking.

Nicotine replacement and medicines to help you stop

Advice and day-to-day support are the basis of stopping smoking in pregnancy. If they are insufficient, nicotine replacement with medical guidance may be considered, for example gum or patches. It avoids cigarette combustion products, but needs to be chosen and used appropriately. The IQWiG information on nicotine replacement therapy explains this assessment.

NICE NG209 also includes nicotine replacement alongside behavioural support. Your clinician must assess which products suit your circumstances during pregnancy or breastfeeding; advice for adults who are not pregnant cannot simply be applied. This includes prescription stop-smoking medicines.

Cutting down may be a step towards stopping, but does not amount to being smoke-free. Exposure to harmful substances may not fall in direct proportion to cigarette numbers if inhalation becomes stronger or deeper. A relapse is therefore a reason to review your support and triggers.

Cannabis in pregnancy: what the research shows

THC, the main intoxicating constituent of cannabis, can cross the placenta. No safe dose has been established for pregnancy. Being plant-based or used only at weekends is therefore not enough to establish safety.

A meta-analysis published in JAMA Pediatrics in 2025 found adverse associations even after taking important confounding factors, such as tobacco use, into account. The adjusted statistical comparisons, known as odds ratios, were 1.75 for low birth weight, 1.52 for preterm birth and 1.57 for a baby being small for gestational age. These figures are not percentages of affected children and do not predict an individual's outcome.

An overview of evidence by Munn and colleagues including 89 studies and reviews also describes adverse associations with several growth and neonatal outcomes, including intensive care. Evidence on later development, learning, behaviour and mental health is less consistent in some respects.

These mainly observational studies do not prove that cannabis caused every difference identified. Amount used, timing, assessment by questionnaire or testing, and accompanying tobacco use influence the conclusions that can be drawn. A single study with no concerning findings cannot answer every question either. Professional bodies therefore recommend avoiding cannabis during pregnancy and breastfeeding.

Cannabis products: flowers, hashish, vapes, edibles and CBD

Cannabis includes very different products. Alongside frequency, discuss THC strength, how it is used, potential additives and whether it is mixed with tobacco. A label that appears medical does not establish suitability for pregnancy or breastfeeding.

Flowers and hashish

The form and active ingredient content differ, but both can supply THC. Smoking adds exposure to combustion products; mixing with tobacco brings tobacco's risks too.

Vapes, dabbing and concentrates

Reducing conventional combustion does not remove THC exposure. Concentrates can contain high amounts of active substances; additives and the actual ingredients create further uncertainty.

Edibles, drinks and capsules

After eating or drinking cannabis, effects may start later and last longer. This makes it easier to take another dose before the first has fully worked. An unexpectedly strong effect can contribute to anxiety, a racing heart and accidents. The CDC information on cannabis explains these acute risks. Avoiding smoke does not mean avoiding risk here either.

Oils, drops and CBD

CBD does not cause the same intoxication as THC, but has not been studied enough to establish safety in pregnancy or breastfeeding. Products sold without prescription can also contain unexpected THC or contaminants.

The FDA information on cannabis and CBD explains why CBD is not a proven safe substitute. Product form changes particular risks, but cannot replace safety evidence.

Nausea, sleep problems and medical cannabis

If you use cannabis for nausea, pain, anxiety or insomnia, those symptoms need an effective solution. Feeling temporarily better does not, however, prove that treatment is safe or appropriate in pregnancy. The 2025 ACOG recommendation advises using alternatives that have been studied more thoroughly.

This includes prescribed medical cannabis. Discuss plans for a baby or an existing pregnancy early with the prescribing clinician and your pregnancy care team, so that the underlying illness can continue to be treated. A prescription does not provide general proof of safety during pregnancy and breastfeeding.

If you can hardly keep fluids down, are losing weight, pass very little urine or feel faint, seek prompt medical assessment. Severe pregnancy sickness should not be managed by experimenting with edibles or vapes.

When cannabis causes vomiting: cannabinoid hyperemesis

Regular cannabis use can cause cannabinoid hyperemesis syndrome, or CHS: repeated episodes of severe vomiting and abdominal pain, which can be confused with pregnancy sickness. Some people get temporary relief from hot showers or baths. A case series of CHS during pregnancy describes this pattern.

Hot water is not a reliable home test or a recommended treatment. Ongoing vomiting needs assessment for dehydration and other causes. Stopping cannabis is central to CHS management; using more for what seems to be nausea can perpetuate the problem. Feeling better after stopping does not remove the need for acute care.

Breastfeeding: assess alcohol, nicotine and THC separately

After birth, the questions change. Breast milk is one consideration; smoke-free surroundings and a consistently sober carer matter too. Using a substance does not lead to the same breastfeeding decision in every case.

Alcohol and breast milk

Avoiding alcohol is safest. Alcohol enters breast milk, and its concentration in milk falls as the level in the blood falls. Expressing and discarding milk does not speed its removal. You can express for comfort or to maintain milk production if needed, but that does not make it possible to breastfeed sooner.

As a guide, the US public health agency CDC gives a minimum interval of two hours per standard drink. Here a standard drink means 14 grams of alcohol, approximately 150 millilitres of wine at 12% alcohol by volume; a large glass may contain substantially more. More alcohol requires more time, and actual clearance varies. Arrange previously expressed milk or suitable infant formula if needed. Premature babies, unwell babies or repeated drinking require individual advice. These timings do not apply to cannabis or other drugs.

Smoking, nicotine and breastfeeding

Nicotine and other substances can pass through milk; smoke exposes the baby through the environment as well. If you have not yet managed to stop smoking, breastfeeding is not automatically ruled out on that basis alone. Practical help and reducing exposure matter: smoke outside, keep your home and car smoke-free, and wash your hands and change smoke-exposed clothes before contact with the baby. The CDC advice on tobacco and breastfeeding stresses this distinction.

Cannabis, THC and breastfeeding

THC dissolves in fat and can enter breast milk. Clearance varies greatly; a urine test measures neither the THC content of milk nor whether breastfeeding is safe. A fixed waiting time or one session of expressing cannot therefore reliably ensure safety. ACOG recommends avoiding cannabis but does not regard continued use as an automatic reason to stop breastfeeding. Discuss the product, frequency, last use and your baby's feeding with your clinician.

Other drugs and prescribed treatment

During current non-prescribed use of opioids, stimulants such as cocaine or sedating sleeping medicines, the Academy of Breastfeeding Medicine recommends temporarily avoiding breastfeeding. Ensure that the baby has suitable feeds and get advice about when breastfeeding can restart. Stable, medically supervised substitution treatment, for example with methadone, needs a different assessment and may be compatible with breastfeeding. The medicines, dose, other substances used and the baby's condition all inform this decision.

Sober care and preventing accidental ingestion

A person who is intoxicated or very drowsy cannot safely look after a baby alone. Arrange for a sober adult to help. After alcohol, cannabis or medicines that make you sleepy, do not sleep in the same bed as the baby or with the baby on a sofa. A separate cot is also important if a carer smokes. The BIÖG advice on sleeping environments explains these risks.

Store cannabis products, e-liquids and medicines locked away, out of children's sight and reach. Cannabis edibles in particular may be mistaken for sweets; nicotine-containing liquids can also cause serious poisoning. Read more about feeding choices in Breastfeeding or not breastfeeding.

Testing, private sperm donation and medical assessment

A period without substance use does not replace a semen analysis or infection testing. A home sperm test likewise cannot establish that a donation is medically safe. In private sperm donation, verifiable health records, appropriate examinations and clear agreements remain separate requirements.

Semen analysis and, where appropriate, further investigations are useful if pregnancy has not occurred, there are known risks or the history raises concerns. The WHO guideline on infertility describes a structured diagnostic approach. Abnormal results should not be attributed solely to lifestyle without due assessment.

After anabolic steroid use, with ongoing erection difficulties, substantial loss of libido or abnormal testicular findings, an early assessment by a urologist or andrologist is sensible. Sudden severe testicular pain, swelling, or pain with fever need rapid assessment. A new lump or repeated blood in semen should also be investigated. The guide to semen and sperm explains the basic terminology.

A realistic plan for the weeks ahead

For men preparing to conceive, eight to twelve weeks can be a manageable time to change habits and plan a follow-up appointment. It is not a biological guarantee or advice to delay a necessary investigation. In pregnancy, the priority is to avoid further exposure as soon as possible, with medical help where dependence is involved.

1. Write down substance use, medicines and the situations in which you use them. Include vapes, nicotine pouches, cannabis oils, steroid cycles and using substances together.
2. Choose practical next steps: help to stop smoking, an assessment appointment, or treatment for poor sleep, anxiety, pain or nausea.
3. Agree on smoke-free rules at home and in the car, and arrange support from those around you. Plan suitable drinks for celebrations and ways of managing triggers.
4. Choose alternative actions for recurring triggers, such as the coffee break, a car journey or an evening after an argument.
5. Set a date to review what is working and what further help is needed. Include relapses in that review without giving up the whole plan.

A booked advice appointment or a plan for the next difficult moment is more helpful than promising to do everything perfectly from now on.

Celebrations, alcohol-free drinks and support around you

At social occasions, order a suitable drink straight away or take one with you. Ask people you trust not to refill your glass or suggest exceptions. A brief refusal is enough; you need not explain a pregnancy or your health history in public.

A drink labelled alcohol-free is not necessarily entirely without alcohol in every product category. Check the actual label. If beer-like or wine-like drinks trigger cravings, choose a different drink.

Partners, relatives and friends can avoid pressuring you to use substances, help with tasks and uphold smoke-free rules. Blaming or downplaying comments make honest conversations harder. Support remains valuable after birth, when tiredness and stress can bring old habits back.

When to seek help and where to start

Seek support if you continue using despite intending to stop, lose control of amounts, use secretly, or need alcohol or cannabis to sleep or cope with the day. Severe agitation, panic, depressive symptoms or repeated vomiting also require medical assessment.

If alcohol dependence is possible, withdrawing without supervision is dangerous, particularly after previous shaking, sweating or seizures. The WHO recommendations on alcohol withdrawal emphasise supported treatment. Benzodiazepines taken regularly should also not be stopped suddenly, because severe withdrawal is possible. For seizures, breathing difficulties, confusion or reduced consciousness, call 112 in Germany.

A GP, gynaecology practice, midwife or addiction advice service can help you take the first step. In Germany, the BIÖG addiction and drugs helpline offers initial guidance, and rauchfrei-info supports stopping smoking in pregnancy.

Four details are useful in the discussion: what you take, how often, why you use it and what happens if you pause. Also explain whether you are pregnant, breastfeeding, or planning sperm donation or treatment. This helps turn general advice into a specific treatment plan.

The law cannot replace a health assessment. Germany's Consumer Cannabis Act has been in force since 1 April 2024; the German Federal Ministry of Health information on the Cannabis Act explains the legal framework. Legal permission is not medical approval for use during pregnancy or breastfeeding.

Common myths that make choices harder

One episode of use proves that everything is already damaged.

Exposure does not prove harm. An honest assessment, avoiding further exposure and getting appropriate help are what count.

Normal semen analysis results make further substance use harmless.

The test assesses particular semen parameters. It is not a comprehensive health check or a statement about the safety of a later pregnancy.

Plant-based, smoke-free or prescribed always means safe.

These features answer different questions. None replaces evidence for the particular use when trying for a baby, during pregnancy or while breastfeeding.

A few cigarettes or using only at weekends is guaranteed harmless.

Reduced exposure can be progress, but is not an established safe limit. Amount, product and circumstances remain relevant.

Testosterone boosts masculinity, so it also increases sperm production.

Testosterone introduced from outside the body can suppress sperm production. Plans to have children therefore belong early in discussions about treatment.

Expressing milk removes alcohol or THC from the body faster.

Expressing does not speed up alcohol clearance or make THC elimination reliably predictable.

A relapse means there is no point trying to stop.

A relapse shows where additional support is needed. The next step without smoking or substance use is still worthwhile.

Conclusion

Alcohol, nicotine and cannabis call for different answers at different stages. Starting to stop early, avoiding further exposure and getting specialist support for dependence are sensible steps. Previous use is not proof of harm, and an unremarkable test does not establish that further use is safe. What matters is a practical plan and suitable support.