How Medicines Affect Your Baby
They seem innocent enough and they’re designed to help you, so just why and how can medicines affect your baby? Unfortunately medicines that you take can cross the placenta and enter into your baby’s bloodstream. The effect it has on your baby depends on several factors, such as what the particular medicine is and when you take it. For example, some medicines are dangerous when taken during the first trimester, but safer later in pregnancy.
Medicines taken in the first trimester often pose the greatest risk as this is the time when your baby’s key organs are developing. If taken during this time, the medicine may affect development, which could potentially lead to birth defects or even miscarriage.
In general, the second trimester is regarded as being the safest time to take medicines if you really have to. However, medicines taken then can cause problems too, particularly in relation to the development of your baby’s nervous system and growth, which could lower birth weight. The third trimester is also a crucial time and some medicines can cause complications when taken, including causing breathing difficulties for your baby.
In addition, medication taken at any time during pregnancy can have an effect on the environment in the womb, which then impacts on your baby. For example, some medicines can bring on contractions in the womb, and others bring on early labour or delayed labour.

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If you regularly take medicines, it’s important to ensure your doctor or pharmacist knows you’re pregnant. The medicines you take may be fine, but then again they may need to be changed slightly for the duration of the pregnancy. Above all, it’s important that those prescribing the tablets know the full facts about your health, so they can make the best decision regarding which medication would be best for you.
Likewise if you’re unwell and find yourself in a position where you need to be prescribed medication, it’s crucial to let your doctor or pharmacist know you’re pregnant. Whatever you do, don’t suddenly stop taking regular prescribed medicine the moment you discover you’re pregnant, as it’s not going to do any good if your own health takes a nosedive because of it. Always discuss alterations to your medication regime with your doctor and don’t make changes without getting medical advice.
Whilst the effects of some medicines are well known and documented, in other cases the situation is unclear and there’s no definite evidence. This is another reason why it’s important to let everyone prescribing drugs know you’re pregnant, as they may need to weigh up the pros and cons of you taking it. In some cases, it may be better in the long run for your baby if you don’t have the medication – even if it means you suffering a bit more with minor ailments. Decisions about this will be made in conjunction with you though, so you can have a say in what you’d prefer to do.
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Other Issues to Bear in Mind
As well as prescription medicines, you need to take care when using other types of medicine too. Over-the-counter medicines for common ailments, such as colds, flu or heartburn can be dangerous too. Always consult a pharmacist before taking them or carefully read the small print, to ensure they are okay for use during pregnancy.
Additionally, herbal remedies and so-called natural alternatives may give the impression of being ‘safe’, but this isn’t always the case. Again, always consult a qualified herbalist, pharmacist or doctor before taking them and don’t self-prescribe.
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