Breastfeeding Fertility of woman and man Pregnancy

Medication during preconception, pregnancy and breastfeeding: This is what you need to know

pregnant woman holds different drugs and medicines in her hand

During  preconception, pregnancy and breastfeeding parents will want to consider carefully whether and which medication to use. “More than half of all pregnant women take medication in the first trimester” says Prof Dr med. I. Gerhard in her book “Frauengesundheit” (Women’s Health).

Why certain medications can be a problem when trying to conceive, during pregnancy and breastfeeding

The potential problem with medication during preconception, pregnancy and breastfeeding lies in the fact that many medications can have various effects on the body. Some of them may affect fertility, foetal development and the health of the breastfed baby.

Probably the best-known example is thalidomide. Its use in the 1960s was associated with serious malformations in children. Nowadays, such dramatic effects are fortunately extremely rare, as the regulations of the current Medicines Act are very strict. Authorities only authorise medicines for pregnant women under two conditions: Either clinical studies have been carried out in which the effects of the drugs have been tested on expectant mothers, or there is decades of experience that rules out any harmful effects on the unborn child with a high degree of certainty. In the absence of such data, the use of the medication is not recommended – even if it is unclear whether there is any harmful effect at all. In cases of doubt, safety is paramount!

Particular caution is required between the 6th and 12th week of pregnancy, as the child’s organs are being formed during this period. Severe exposure to drugs during this phase can lead to permanent damage. Towards the end of pregnancy the risks are significantly lower. It is essential to seek medical advice and only take medication under strict medical supervision.

Remember that the embryo in your womb and later the newborn also absorb the active ingredients.

Prof Dr med I Gerhard

From preconception to the end of breastfeeding, it is ideal if you first try appropriate alternative medicine, depending on your symptoms. For example, acupuncture and relaxation techniques can alleviate headaches during pregnancy. Use an extra pillow to elevate the body and chew oatmeal or almonds slowly to help with heartburn during pregnancy. Acupressure or ginger work well for nausea in the first trimester. (Use only small amounts of ginger, it may promote labour in large quantities).

However, there are situations in which treatment with home remedies and natural alternatives alone is not sufficient. In the case of severe allergies, chronic illnesses, diabetes, epilepsy or serious infections, treatment with medication is usually unavoidable. In such cases, it is always best to consult your doctor first instead of self-medicating.

These medications are suspected of lowering female fertility

Antidepressants, neuroleptics, high blood pressure medication and anti-rheumatic drugs such as methotrexate (MTX) have been examined for their fertility-lowering effects. Drugs used in cancer therapy can also have fertility-damaging properties.

An Australian study has shown that women who take certain asthma medications may have lower fertility. Short-acting beta antagonists (SABA), also known as relievers, may increase the time to pregnancy by an average of 20 per cent. Long-acting beta-antagonists (LABA) and inhaled glucocorticoids (cortisone), on the other hand, do not have a negative effect on fertility and could even protect it.

Another study showed that painkillers and anti-inflammatory drugs such as non-steroidal anti-inflammatory drugs (NSAIDs), which are used to treat rheumatism or back pain, can impair fertility in women just a few days after starting to take them. These drugs could apparently reduce progesterone levels in the second half of the cycle, which are important for ovulation and pregnancy.

These drugs may reduce sperm quality

Various medications can affect the quality of sperm and therefore have an impact on a man’s fertility. These include some antibiotics, anabolic steroids, H2 blockers (active ingredient against heartburn), strong painkillers (opiates), ibuprofen, regular intake of aspirin over a longer period of time, antidepressants, antipsychotics, tranquillisers, antiepileptics, antiemetics, antifungals, antirheumatics, gout medication. Adrenal steroids (e.g. cortisone), lithium, antihistamines (for allergies, especially cetirizine), Parkinson’s drugs, sulphonamides for inflammation and drugs for high blood pressure, especially from the group of aldosterone antagonists and calcium antagonists, can impair sperm quality. Some antihypertensives (blood pressure-lowering drugs) can also massively impair sperm motility. It is therefore important to seek medical advice if you wish to have children and to consider possible alternatives.

Special care must be taken with these medications during pregnancy

Sleeping pills, especially the benzodiazepine group, can lead to congenital muscle weakness, the so-called “floppy infant syndrome”. ACE inhibitors, a group of antihypertensive drugs, can cause kidney and liver damage in the child and must also not be taken.

pregnant woman takes medication

Caution is also advised with antibiotics. While penicillins and erythromycin are generally unproblematic, tetracycline and the aminoglycoside group should be avoided. Tetracycline can lead to permanent discolouration of the teeth, and gentamicin and kanamycin can damage the child’s hearing.

Painkillers are generally permitted in normal doses. With non-steroidal anti-inflammatory drugs (NSAIDs) such as acetylsalicylic acid and ibuprofen, there is a theoretical risk of premature labour if they are taken regularly in the third trimester of pregnancy. Paracetamol is considered a safer alternative. Cortisone and asthma medication are generally harmless.

The situation is particularly complex for women with epilepsy. Carbamazepine can lead to malformations, but discontinuation of the anti-epileptic drug harbours the risk of epileptic seizures that could endanger the child. Intensive consultation with the treating specialist is therefore essential.

If you are unsure about the use of medication during pregnancy and breastfeeding, please consult your doctor.

Gentle and yet sometimes critical: herbal medicines

Herbal remedies are considered to be rather gentle and, above all, natural. Nevertheless, you should not take them without consultation.

Prof Dr med I Gerhard in “Women’s Health”

Natural remedies and herbal mixtures are often regarded as natural alternatives to certain medications. However, like medicines, they can have undesirable side effects during pregnancy. Although a cup of chamomile tea is generally safe for pregnant women, some plants contain essential oils or other substances that can harm the baby or trigger premature labour.

medical plants

Use these plants sparingly during your pregnancy:

– Aniseed and aniseed oil (Pimpinella anisum):  Stimulates the uterus in large quantities; however, largely harmless as a kitchen spice. Avoid oil.

– Fenugreek (Trigonella foenum-graecum):  Stimulates the uterus in large quantities; however, largely harmless as a kitchen spice and during labour.

– Chilli (Capsicum spp):  Avoid large amounts as it can cause heartburn; moderate use is unproblematic.

– Verbena (Verbene officinalis): Stimulates the uterus in high doses; best used only in the last weeks of pregnancy and during labour.

– Angelica (Angelica archangelica): Stimulates the uterus in large quantities; however, it is largely harmless as a kitchen spice.

– Fennel and fennel oil: Stimulates the uterus in large quantities, but is largely harmless as a culinary spice. Avoid fennel oil.

– Ginseng (Panax ginseng):  Large amounts could lead to androgenic babies; do not use over a long period of time.

– Raspberry leaves (Rubus idaeus):  Relaxes the uterus and can lead to premature opening of the cervix; in the last six to eight weeks of pregnancy and during labour, raspberry leaf tea can ease the birthing process.

– Jasmine oil: Stimulates the uterus; save it for the birth to relieve labour pain; has a relaxing effect.

– Camomile oil: Strongly stimulates the uterus, but fresh or dried the plant is harmless with moderate use.

– Garlic (Allium sativa):  Avoid large amounts as it can cause heartburn; moderate use is unproblematic.

– Caraway (Carum carvi):  Stimulates the uterus in large quantities; however, largely safe as a kitchen spice.

– Liquorice (Glycyrrhiza glabra):  Can increase blood pressure in large quantities; use sparingly.

– Lavender (Lavendula angustifolia):  Stimulates the uterus in large quantities; however, largely harmless as a kitchen spice and in small quantities.

– Lovage (Levisticum officinale):  A uterine stimulant, commonly used in protracted labour; safe as a culinary spice.

– Marjoram (Origanum X marjoricum; O. onites):  Stimulates the uterus in large quantities; the oil should be avoided, but largely safe as a kitchen spice.

– Nutmeg and nutmeg oil: May impair hormone production and contain hallucinogens; safe as a kitchen spice.

– Oregano and oregano oil (Origanum vulgare):  Stimulates the uterus in large quantities; however, largely safe as a kitchen spice; avoid the oil

Medication during breastfeeding

Breastfeeding mothers who need medication will want to check that the medicine is suitable for use during breastfeeding before using it.

Some medications, such as epinephrine, heparin and insulin, do not pass into breast milk and are therefore safe to take. Most medications are found in breast milk, but often in minimal amounts. Nevertheless, some medications, albeit in small amounts, can be harmful to the baby.

Examples of relatively harmless medications during breastfeeding are paracetamol and ibuprofen in normal amounts. Drugs for the skin, eyes or nose and most antihypertensives generally have no significant effect on breastfed babies.

For some medicines, medical supervision is required to adjust the dosage, duration and timing of use in relation to breastfeeding.

For example, warfarin, an anticoagulant drug, can be taken while breastfeeding, but requires regular blood tests to ensure that blood clotting remains normal.


If you have to take a medication while breastfeeding that could harm your child, you should temporarily stop breastfeeding. However, you can resume breastfeeding once you have stopped taking the medication. To ensure that your milk production does not come to a standstill during this time, you can express your milk (but unfortunately you will have to discard it).  Your doctor can prescribe a breast pump for you to borrow during this time.

Medicines that require you to stop breastfeeding include, for example

– Amphetamines

– Chemotherapy drugs (such as cyclosporine, doxorubicin and methotrexate)

– Chloramphenicol (an antibiotic)

– Ergotamine (used to treat migraine headaches)

– Lithium

– Radioactive substances for diagnostic purposes

– Illegal drugs such as cocaine, heroin and phencyclidine (PCP)

Medication that can reduce milk flow

You should be careful with some medications as they can affect the flow of milk. These include, for example:

– Bromocriptine (used to treat Parkinson’s disease)

– oestrogens

– Oral contraceptives with high oestrogen and progestin content

– Trazodone (an antidepressant)

– Levodopa

Certain plants can also inhibit milk production, including sage, peppermint and hibiscus. Other substances, such as St John’s wort and certain bitter substances, for example artichoke extract, pass into breast milk and can cause your little one to have stomach ache.

PS: Think about your nutrient supply

During breastfeeding, the energy requirement increases by an estimated 500 kcal/day due to milk production, which is more than during pregnancy. The need for minerals (such as iodine, zinc and magnesium), vitamins (such as B6 and vitamin E) and other nutrients (such as omega-3 fatty acids and choline) also increases significantly. If you need additional medication, this often results in an even greater need, which you should definitely try to cover. If you want to be on the safe side during the stressful baby period, you can take special prenatal and breastfeeding vitamins during this phase.

In summary, it is advisable to discuss the intake of medication with your doctor at an early stage from the time you want to have children until the end of the breastfeeding period. There are often alternative medications available that do not affect fertility, pregnancy or the health of your baby. If no alternatives are available, you should discuss with your doctor whether it is absolutely necessary to take the medication or whether it can be temporarily discontinued. It is generally advisable not to use any medication without consulting a doctor. Even supposedly harmless herbal preparations may require a closer look.


European League Against Rheumatism (EULAR): Non-steroidal anti-inflammatory drugs inhibit ovulation after just 10 days. Pressemitteilung von EULAR (StandJuni 2015);

Gaytán M, Morales C, Bellido C, Sánchez-Criado JE, Gaytán F. Non-steroidal anti-inflammatory drugs (NSAIDs) and ovulation: lessons from morphology. Histol Histopathol. 2006 May;21(5):541-56. doi: 10.14670/HH-21.541. PMID: 16493584.

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Leverrier-Penna S., u.a.: Ibuprofen is deleterious for the development of first trimester human fetal ovary ex vivo. Human Reproduction, Volume 33, Issue 3, 1 March 2018, Pages 482–493;

Mendonca, L. L. F. et al. (2021). Non‐Steroidal Anti‐Inflammatory Drugs as A Possible Cause for Reversible Infertility. Rheumatology.

European League Against Rheumatism. “Non-steroidal anti-inflammatory drugs inhibit ovulation after just 10 days.” ScienceDaily, 11 June 2015.

I Gerhard: Frauengesundheit. Ganzheitliches Heilwissen für Körper und Seele. Trias Verlag, 3., überarbeitete Auflage, 2021

About the author

Dr. rer. nat. Birgit Wogatzky

For many years now, biologist and nutritionist Dr Birgit Wogatzky, has been focusing on the special needs of fertility patients. For the readers of this blog, she sums up interesting novel information and developments from current research projects regarding lifestyle and nutrition of fertility patients.