Alcohol, nicotine and cannabis when planning a pregnancy, during pregnancy and while breastfeeding

Three stages, three different questions

You might be a sperm donor who wants to improve your test results. You might have a positive pregnancy test and be thinking about last weekend. Or you may be breastfeeding and wondering what can still enter your milk after substance use. These situations are connected, but they cannot all be addressed with the same rule.

Before pregnancy

This is about fertility, sperm, hormones and sexual function, as well as a pregnancy that may already have started. Planning should include the person hoping to become pregnant and your shared environment too.

During pregnancy

Certain substances can reach the baby through the placenta. The pregnant person's health, the baby's supply through the placenta and additional exposure to smoke are also important.

While breastfeeding

Substances in breast milk, smoke in the surroundings and safe infant care all matter. How quickly something clears from the body and what feeding plan is appropriate depend on the substance.

A finding about a future father's drinking therefore does not show that alcohol is safe during pregnancy. Conversely, one evening before conception cannot reliably predict a child's health.

What substance use can reveal about sperm and fertility

Sperm form and mature over weeks. A semen analysis does not simply show whether yesterday was a healthy day. Fever, the time without ejaculation before collection, collecting an incomplete sample and differences between tests can affect the results. Sleep, medical conditions and your circumstances over the longer term should also be discussed.

Normal results are not a complete health clearance. The reference values in the WHO laboratory manual do not create a sharp boundary between fertile and infertile. When findings are abnormal, a clinician's assessment determines if and when testing needs to be repeated.

In substance-use research, the outcome measured is important: sperm count and movement are different outcomes from pregnancy or live birth. Other substances, medical conditions and accompanying factors can influence associations. Better semen parameters therefore do not guarantee pregnancy.

Alcohol in men: the amount and pattern both matter

For male fertility, prolonged heavy drinking is especially relevant. It may be linked to changes in hormonal regulation and testicular function. Findings for small or occasional amounts are less clear. Saying one beer destroys sperm would be as inaccurate as giving a blanket assurance that regular binge drinking is harmless.

Alcohol can also interfere with trying to conceive in daily life, for example through its effects on sleep, sexual desire, erections or reliability in attending appointments. A review of lifestyle and male fertility puts these hormonal, sexual and reproductive associations into context.

At a medical appointment, describing your actual pattern is more useful than calling it occasional: on how many days, about how much, and whether you repeatedly become intoxicated. If you want to reduce substantially, plan several weeks and observe changes in daily life and symptoms. If dependence is present, this step needs medical guidance.

Smoking, nicotine and fertility

Evidence links cigarette smoke with poorer sperm count, movement and shape, as well as damage to sperm DNA. This does not mean that every man who smokes is infertile. Smoking is nevertheless a useful starting point when you want to reduce avoidable exposures.

Tobacco smoke and nicotine are not interchangeable. Cigarettes also deliver carbon monoxide and many combustion products. The evidence on vapes and nicotine pouches in human fertility is less extensive; a lack of long-term findings does not prove safety. The ASRM statement on tobacco, nicotine and cannabis makes these distinctions clear.

Smoking also affects the person who wants to become pregnant: in women, tobacco use is associated with reduced fertility and poorer outcomes from fertility treatments. Quitting is therefore relevant to both people involved, including in private sperm donation. A smoke-free environment also reduces second-hand smoke exposure.

Cannabis before conception: findings without clear-cut limits

Studies of cannabis and male fertility show a mixed picture. Some report changes in semen parameters or hormones; others find no clear link with the time it takes to become pregnant. THC strength, frequency, method of use and additional tobacco use vary widely. ASRM therefore interprets these links more cautiously than the well-established risks of smoking.

If you are actively trying to conceive or have abnormal findings, discussing cannabis openly and planning to stop is sensible. This reduces a possible exposure without promising that a certain number of substance-free days returns everything to normal. If cannabis is mainly used to fall asleep or manage anxiety, appropriate treatment for those symptoms should be part of the plan.

If you could become pregnant, do not base your decisions only on sperm studies. Recommendations to avoid cannabis in a possible early pregnancy apply even before a positive test.

Testosterone and anabolic steroids are a special case

Testosterone introduced from outside the body can suppress the hormonal signals the testes need to make sperm. The sperm count can drop substantially, or production can stop completely. More muscle, increased libido or a high testosterone level does not therefore automatically mean better fertility.

The AUA/ASRM male infertility guideline advises against testosterone monotherapy for anyone interested in current or future fertility. This applies to prescribed treatment, steroid cycles and self-medication for fitness alike.

Discuss the product, dose and duration with a urologist or andrologist. Recovery can take months and sometimes longer; there is no fixed recovery deadline. Do not discontinue prescribed treatment yourself or attempt to restore sperm production with hormone products you combine on your own.

Opioids, cocaine and other substances

Drugs and semen are not just a question of cannabis. Opioids can affect hormonal signalling, libido and sexual function. Cocaine and other stimulants bring substantial risks to the heart, circulation and mental health. Research does not allow a dependable ranking of doses that are safe for conception.

Prescribed pain treatment or care for opioid dependence is different from uncontrolled substance use. Methadone or buprenorphine can be part of recommended care for opioid dependence during pregnancy. Do not stop without advice: the CDC recommendations on opioid dependence in pregnancy emphasize the value of coordinated treatment. Newborns may develop withdrawal symptoms after opioid exposure, so inform the birth team early. This risk does not justify leaving out necessary treatment.

Severe drowsiness, slow breathing, chest pain, seizures or unconsciousness call for urgent medical attention. These are not symptoms that should wait for the next fertility appointment.

Understanding sugar and combined substance use

Sugar is not in the same risk category as tobacco smoke or anabolic steroids. Eating dessert does not suddenly make sperm unusable. A diet that stays very high in calories can affect weight and metabolism; this is different from a direct effect of drugs. Marked fatigue or a loss of sexual desire should not be attributed to sugar alone without further assessment.

Combined use, however, is directly relevant. Alcohol, tobacco and cannabis can overlap in daily life and make abnormal test results harder to interpret. Combining alcohol with opioids or sedatives such as benzodiazepines is especially dangerous: their depressant effects can intensify and impair breathing. The FDA warning about opioids and sedating substances highlights this risk.

Include medications and your reasons for using them, such as sleep problems or anxiety. Help with quitting and treatment of these symptoms belong together. Supplements cannot undo the effects of substance use or replace that care; see the guide to supplements when trying to conceive.

Alcohol during pregnancy: no established safe limit

Alcohol can pass through the placenta to the embryo or fetus. No safe amount, safe timing or safe type of drink has been established for pregnancy. The recommendation is therefore to avoid alcohol throughout pregnancy. This also applies when you want to conceive and pregnancy is already possible. The CDC information about alcohol during pregnancy explains the recommendation.

A safe limit cannot be tested experimentally on pregnant people. Research therefore relies mainly on observational studies, which do not always record amounts and accompanying factors completely.

Large amounts of alcohol over a short period produce high concentrations in the blood. Binge drinking of this kind is particularly concerning, but smaller amounts used repeatedly are not automatically safe. Beer, wine, sparkling wine and spirits differ in alcohol concentration, not in whether their alcohol can reach the baby.

Organs start forming in the early weeks, while brain development continues throughout pregnancy. There is no later point at which drinking becomes reliably harmless. At the same time, earlier exposure does not mean that harm has definitely occurred.

FASD and other possible effects of alcohol

Fetal alcohol spectrum disorders, or FASD, describe various possible effects of prenatal alcohol exposure. Growth, physical development, learning, memory, attention, planning and impulse control may be affected. Problems with behaviour and emotional regulation sometimes become visible only as everyday expectations increase.

Physical signs can include a smaller head circumference or growth difficulties. 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. Their absence does not exclude alcohol-related developmental problems.

FAS and pFAS

Fetal alcohol syndrome and partial fetal alcohol syndrome are diagnostic labels within the spectrum.

ARND and ARBD

These terms mean alcohol-related neurodevelopmental disorders and alcohol-related birth defects, respectively. Diagnostic categories differ among guidelines.

The CDC overview of FASD explains the terms; in Germany, the AWMF guideline on FASD in children and adolescents is relevant to diagnosis. Diagnosis belongs with experienced professionals and cannot be inferred from the amount someone drank or a single physical feature.

Alcohol use in pregnancy is also associated with miscarriage, preterm birth and other adverse pregnancy outcomes. A reassuring ultrasound is helpful, but cannot rule out every later learning and developmental effect. An adverse outcome does not automatically mean earlier alcohol use caused it either.

Use before the positive test: what helps now

Many pregnancies are not noticed until a few weeks have passed. If you drank alcohol, smoked or used cannabis beforehand, the first task is to avoid further exposure and discuss the situation during prenatal care. One past exposure is not proof of lasting harm.

Record the period, approximate amounts, repeated use or binge drinking, and any other substances involved as honestly as possible. You do not need a perfect calculation down to the millilitre. These details are meant to help with counselling, not lead to an endless search for a guarantee about the past.

One clear question for the appointment is which checks and support make sense now. If alcohol dependence or previous severe withdrawal may be involved, arrange medical help that day for safe withdrawal. This particular situation must not be confused with advice to keep smoking cigarettes.

Smoking during pregnancy and after birth

Smoking combines several exposures. Carbon monoxide reduces oxygen transport in the blood; nicotine and other smoke components affect the pregnant person's body and the child's development. Well-established risks include growth problems, low birth weight and preterm birth. Placental complications are also among the risks.

Smoke remains relevant after delivery: second-hand smoke increases infants' risks of sudden infant death syndrome, lower respiratory illnesses and middle ear problems, among others. The CDC overview of smoking and maternal and infant health summarizes the findings.

Ideally, stop smoking before pregnancy. Stopping later is still worthwhile because it removes further exposure. One cigarette or a relapse does not erase the benefits of the time you have already spent smoke-free. What matters is becoming smoke-free again and addressing the trigger.

Vapes, hookah, snus and nicotine pouches

A product without combustion is not automatically without risk. Describing all products as equally harmful would also be inaccurate. Decisions require separate consideration of smoke constituents, nicotine, additives and the evidence available for each product.

E-cigarettes and vapes

These avoid some combustion products found in cigarettes, but can deliver nicotine and other substances in the aerosol. They have not been established as safe alternatives in pregnancy. Nicotine-free e-liquids are not reliably tested pregnancy-safe products either.

Hookah

Water does not reliably filter away harmful exposure. Smoke and carbon monoxide still matter, and lengthy sessions can cause substantial exposure.

Snus and nicotine pouches

Snus contains tobacco; nicotine pouches may not. Both can deliver nicotine. Being smoke-free therefore does not make them safe during pregnancy or equivalent to a medically planned approach to quitting.

The CDC information on vaping's health effects explains risks and gaps in evidence. If you have already switched products, talk about a sustainable next step. Returning to cigarettes is not the answer. The goal is to be smoke-free and, where possible, nicotine-free with support you can actually use.

Second-hand smoke: keep the home and car smoke-free

Regular smoke exposure in your surroundings matters even if you do not smoke yourself. Risks from second-hand tobacco smoke in pregnancy and infancy are established. Cannabis smoke is also unsuitable around pregnant people or babies; using it with tobacco combines the two exposures.

An open window, moving to another corner or briefly airing the room does not turn a smoky indoor space into a reliably protected environment. Cars are especially confined. The practical rule is to avoid smoking in the home and car, including when the baby is not there.

Partners, family members and visitors can support this rule without daily negotiations over exceptions. More practical information is available from Kindergesundheit-Info on second-hand smoke.

Nicotine replacement and medications for quitting smoking

Counselling and daily support are the foundation of quitting during pregnancy. If those are not enough, medically supervised nicotine replacement, such as gum or patches, may be appropriate. It avoids cigarette combustion products, but must be selected and used properly. The IQWiG information on nicotine replacement therapy explains this balance.

NICE NG209 also includes nicotine replacement with behavioural support. Your clinician needs to assess which options fit your circumstances during pregnancy or breastfeeding; recommendations for nonpregnant adults cannot simply be carried over. This applies to prescription stop-smoking medications as well.

Cutting down can be an intermediate step, but is different from being smoke-free. Exposure to harmful substances does not necessarily drop in proportion to cigarette numbers if you inhale more strongly or deeply. A relapse is therefore a reason to reconsider support and triggers.

Cannabis during pregnancy: what studies find

THC, the main intoxicating ingredient in cannabis, can cross the placenta. No safe dose has been established for pregnancy. Plant-based or only on weekends therefore does not provide an adequate assurance of safety.

A 2025 meta-analysis in JAMA Pediatrics found adverse associations even after accounting for important confounders, including tobacco use. Adjusted statistical comparisons called odds ratios were 1.75 for low birth weight, 1.52 for preterm birth and 1.57 for being small for gestational age. These are not percentages of affected children or predictions for an individual.

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

The largely observational studies do not prove cannabis caused every difference found. Amount, timing, measurement by questionnaire or testing, and accompanying tobacco use influence what can be concluded. Nor does one study without adverse findings resolve every question. Professional organizations therefore advise avoiding cannabis in pregnancy and breastfeeding.

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

Cannabis refers to a wide range of products. Along with frequency, discuss THC content, the way you use it, potential additives and mixing with tobacco. A label that looks medical does not establish suitability during pregnancy or breastfeeding.

Flowers and hashish

Their form and active ingredient content vary, but both can provide THC. Smoking adds exposure to combustion products, and adding tobacco brings its risks as well.

Vapes, dabbing and concentrates

Reducing conventional combustion does not remove THC exposure. Concentrates can contain large amounts of active substances; additives and the actual composition are further uncertainties.

Edibles, beverages and capsules

After cannabis is eaten or drunk, the effects may be delayed and last longer. That can lead to taking more before the first dose fully works. An unexpectedly intense effect can contribute to anxiety, a racing heart and accidents. The CDC information on cannabis describes these acute risks. Smoke-free does not mean risk-free here either.

Oils, drops and CBD

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

The FDA information about cannabis and CBD explains why CBD is not a proven safe alternative. Product format changes particular risks but does not replace safety data.

Nausea, sleep problems and medical cannabis

If cannabis is used for nausea, pain, anxiety or insomnia, those symptoms need a solution. Feeling relief in the short term is not evidence that the treatment is safe or appropriate during pregnancy. The 2025 ACOG recommendation advises alternatives that have been better studied.

The same applies to prescribed medical cannabis. Discuss plans to conceive or an existing pregnancy early with both the prescribing clinician and your pregnancy care clinician, so the underlying condition can still be treated. A prescription is not a general assurance of safety during pregnancy and breastfeeding.

If you can barely keep fluids down, lose weight, produce very little urine or feel faint, you need timely medical assessment. Severe nausea in pregnancy should not be treated by experimenting with edibles or vapes.

When cannabis itself triggers vomiting: cannabinoid hyperemesis

Regular cannabis use can cause cannabinoid hyperemesis syndrome, or CHS: recurring severe vomiting and abdominal pain that may be mistaken for pregnancy nausea. Some people get temporary relief from hot showers or baths. A case series on CHS in pregnancy describes this pattern.

Hot water is not a reliable self-test or a treatment recommendation. Persistent vomiting requires assessment for dehydration and other causes. Stopping cannabis is central to CHS care; continued use for what seems to be nausea can maintain the problem. Improvement after stopping does not replace necessary acute care.

Breastfeeding: alcohol, nicotine and THC need separate consideration

After the birth, the questions change. Breast milk matters, but so do a smoke-free environment and a reliably sober person caring for the baby. Substance use does not automatically imply the same breastfeeding decision for every substance.

Alcohol and breast milk

Avoiding alcohol is the safest option. Alcohol enters breast milk; as blood alcohol levels decrease, milk alcohol levels decrease too. Pumping and discarding milk does not speed clearance. If needed, you can express milk for comfort or to maintain production, but this will not allow breastfeeding to resume sooner.

As a guide, the US public health agency CDC advises an interval of at least two hours per standard drink. In that advice, a standard drink contains 14 grams of alcohol, approximately 150 millilitres of wine at 12% alcohol by volume; a large glass can contain much more. Higher amounts need more time, and actual clearance varies. Plan to use previously expressed milk or suitable infant formula if needed. For premature or sick babies, or repeated drinking, individual advice is necessary. This timing does not apply to cannabis or other drugs.

Smoking, nicotine and breastfeeding

Nicotine and other substances can reach the baby through milk, while smoke adds exposure from the surroundings. If you have not managed to quit, breastfeeding is not automatically excluded for that reason alone. Practical support and reduced exposure matter: smoke outside, maintain a smoke-free home and car, and wash your hands and change smoke-exposed clothing before contact with the baby. The CDC recommendations on tobacco and breastfeeding underline this distinction.

Cannabis, THC and breastfeeding

THC is fat-soluble and can enter breast milk. Elimination varies greatly; a urine test measures neither the THC level in milk nor whether breastfeeding is safe. A fixed waiting period or pumping once therefore does not reliably establish safety. ACOG recommends avoiding cannabis, but does not automatically consider ongoing use a reason to stop breastfeeding. Discuss the product, frequency, last use and your baby's feeding with your clinician.

Other drugs and prescribed treatment

With current nonprescribed use of opioids, stimulants such as cocaine or sedating sleep medications, the Academy of Breastfeeding Medicine recommends temporarily avoiding breastfeeding. Ensure appropriate feeding for the baby and ask when breastfeeding can safely resume. Stable, medically supervised substitution treatment, for example methadone, requires a different assessment and may be compatible with breastfeeding. Medications, dose, accompanying substance use and the child's condition all belong in that decision.

Sober caregiving and preventing accidental ingestion

An intoxicated or very drowsy person cannot safely care for a baby alone. Arrange a sober adult to take care of the baby. After alcohol, cannabis or substances that cause drowsiness, do not sleep with the baby in the same bed or on a sofa. A separate crib is also important if a caregiver smokes. The BIÖG guidance on the sleep environment explains these risks.

Keep cannabis products, e-liquids and medications locked away and out of children's sight and reach. Cannabis edibles can particularly easily be mistaken for candy, and nicotine-containing e-liquids can also cause serious poisoning. Read more about feeding decisions in Breastfeeding or not breastfeeding.

Testing, private sperm donation and medical assessment

A period without substance use replaces neither semen analysis nor infection testing. A home sperm test cannot certify that a donation is medically safe either. For private sperm donation, verifiable health information, appropriate examinations and clear agreements remain separate responsibilities.

Semen analysis and further assessment when appropriate are useful when pregnancy has not occurred, known risks exist or the medical history raises concerns. The WHO guideline on infertility describes a structured diagnostic process. Abnormal results should not be quickly attributed to lifestyle alone.

After anabolic steroid use, with persistent erection problems, significant loss of libido or abnormal testicular findings, early assessment by a urologist or andrologist makes sense. Sudden severe testicular pain, swelling or pain with fever need prompt assessment. A new lump or recurrent blood in semen also warrants investigation. The guide to semen and sperm explains the basic terms.

A realistic plan for the coming weeks

For men planning conception, eight to twelve weeks can be a manageable period for changing habits and scheduling follow-up. This is not a biological guarantee or a reason to delay necessary testing. During pregnancy, avoid further exposure as soon as possible, with medical support when dependence is present.

1. Write down substance use, medications and the situations in which you use them. Include vapes, nicotine pouches, cannabis oils, steroid cycles and combined use.
2. Choose specific next steps: smoking cessation support, a medical assessment or treatment for sleep difficulties, anxiety, pain or nausea.
3. Agree on smoke-free rules for your home and car and arrange help from people around you. Plan suitable drinks for celebrations and ways to manage triggers for use.
4. Choose alternative activities for recurring triggers, such as a coffee break, a drive or the evening after an argument.
5. Set a date to review what works and what additional help is needed. Include relapses in this review without giving up the whole plan.

A booked counselling appointment or a plan for the next difficult situation helps more than deciding to do everything perfectly from now on.

Celebrations, alcohol-free drinks and support from others

At gatherings, order a suitable drink at the start or bring one along. Ask trusted people not to refill your glass or suggest exceptions. A brief refusal is enough; you do not need to explain your pregnancy or medical history in public.

An alcohol-free label does not mean every product is completely free of alcohol. Check the specific labelling. If drinks resembling beer or wine trigger cravings, choose another type of beverage.

Partners, family and friends can avoid pressuring you to use substances, help with tasks and support smoke-free rules. Blame or comments that minimize the issue make open conversations harder. Support remains important after birth, when sleep deprivation and stress can make old habits more tempting again.

When support is needed and where to find it

Get support if you continue using despite your intentions, no longer control amounts, use secretly or need alcohol or cannabis to sleep or cope with the day. Severe restlessness, panic, depressive symptoms or repeated vomiting also warrant medical assessment.

If alcohol dependence is possible, withdrawal without supervision is dangerous, especially after previous tremors, sweating or seizures. The WHO recommendations on alcohol withdrawal stress supervised care. Benzodiazepines taken regularly should also not be stopped abruptly, because severe withdrawal symptoms can occur. For seizures, breathing problems, confusion or impaired consciousness, call 112 in Germany.

A family doctor, gynaecology practice, midwife or addiction counselling service can help with the first step. In Germany, the BIÖG addiction and drugs helpline provides initial guidance, and rauchfrei-info offers help with quitting smoking during pregnancy.

Four details help the conversation: what you take, how often, what you use it for and what happens when you take a break. Also say whether you are pregnant, breastfeeding, or planning sperm donation or treatment. This makes it possible to turn a general warning into a concrete care plan.

Legal status cannot replace this health assessment. Germany's Consumer Cannabis Act has applied 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 pregnancy or breastfeeding.

Common myths that make decisions harder

One use proves everything has already been harmed.

Exposure is not certain proof of harm. An honest assessment, avoiding further exposure and suitable help are what matter.

A normal semen analysis makes any further use harmless.

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

Plant-based, smoke-free or medically prescribed automatically means safe.

These characteristics address different questions. None replaces data for that specific use before conception, in pregnancy or while breastfeeding.

A few cigarettes or use only on weekends is guaranteed harmless.

Lower exposure can be progress, but it is not an established safe limit. The amount, product and circumstances remain important.

Testosterone increases masculinity, so it must increase sperm production.

Testosterone from outside the body can suppress that production. Plans for having children should therefore be part of treatment planning early on.

Pumping milk clears alcohol or THC from the body faster.

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

A relapse means quitting will not work anyway.

A relapse shows where the plan needs more help. The next step without smoking or substance use still matters.

Conclusion

Alcohol, nicotine and cannabis need different answers depending on the stage. Starting to quit early, avoiding further exposure and seeking professional support for dependence are practical steps. Past use is not definite evidence of harm; a normal test does not establish that further use is safe. A clear plan and the right support are essential.