Medications during pregnancy
Dr. D. Miguel Ángel Herráiz Martínez, Chief of Obstetrics of the San Carlos Clinical Hospital;
Dr. D. Javier Valero de Bernabé, gynecologist at Hospital Santa Cristina and at the Gynecology and Obstetrics Service at Hospital Universitario de Fuenlabrada
The administration of a drug to a pregnant woman represents a problem for the doctor, since it should not only take into account the woman, but also the fetus / embryo as a potential recipient of that substance.
Pregnant women should never self-medicate , they should first seek advice from their GP or gynecologist to assess the risk-benefit depending on the time of gestation, the maternal illness or symptoms and the drug to be consumed. There are many variables that determine whether or not a drug is suitable during pregnancy. There are drugs, classified as high risk, that should never be administered because they can induce abortions or premature births. Some, on the other hand, that are safe at certain times of pregnancy are not safe in others, a factor to which the number of doses must also be added: some do not represent risk and others should be avoided. In any case, it is always the doctor who values its administration .
Specialists advise, as a general rule, not to take drugs during a fundamental stage of pregnancy called organogenesis. During this period, the first ten weeks of gestation, the fetus develops its vital organs, transforming into an embryo. Organogenesis is especially sensitive for the future baby because any external factor, including an inadequate intake of medications, can cause a malformation or alteration of its growth.
Most frequent pathologies and their treatment
– Headache : in principle there is no contraindication to using drugs containing paracetamol (Gelocatil, Termalgin …).
– Nausea of the pregnant woman : we will try to control them initially with dietary measures (eat little and often, neither very hot nor very cold foods, avoid solid and liquid foods, do not take food if water has not been tolerated before …). If the discomfort does not subside despite dietary measures, it may be necessary to administer an antiemetic.
– Dental and / or gingival problems : it is important during pregnancy to have good dental hygiene, therefore it is advisable to visit the dentist when you are pregnant. If a dental infection occurs, it will be necessary to take an antibiotic.
– Stomach pains : during pregnancy, heartburn, increased reflux, heavy digestion can occur … Antacid-type drugs or gastric protectors are usually used regularly.
– Respiratory pathology : if problems with coughs, colds, pneumonia appear … It will be essential in these cases the assessment by the family doctor, who will be in charge of assessing whether or not the administration of pharmacological treatment is necessary.
– Urinary pathology : the appearance of urine infections in pregnant women is frequent, basically cystitis. In these cases, the duty of the doctor is to diagnose it, once diagnosed, give antibiotic treatment, drink plenty of water and supplement it with vitamin C.
– Nephritic colic : it is another frequent pathology during pregnancy (the clinic is typical with pain in the back, urinary discomfort, etc …). In these cases, a good assessment of the renal status of the patient will be important. If kidney function is normal, analgesic treatment will be essential to calm the pain and drink plenty of water. Also in these cases the local heat has a good response.
– Hemorrhoids : very frequent pathology especially in the third trimester. Most cases are treated with cold and anti-inflammatory local ointments.
– Back problems : due to the weight of the womb, the back of the pregnant woman often suffers. Muscle contractures, sciatica, etc. they can be frequent. Most of the time with rest and local heat it is usually solved, but if circumstances indicate it may be necessary to take an anti-inflammatory (remember not to take anti-inflammatories beyond 34 weeks of gestation if it is not under medical supervision).
Rules for the use of medicines
– Prescribe only the necessary medication.
– Avoid drugs of recent appearance or with little proven experience.
– Use the minimum dose and for the shortest time possible.
– Avoid the prescription of several medications at the same time.
– Avoid as far as possible the prescription during the first trimester.
– Never self-medicate.
– Avoid harmful habits such as alcohol or tobacco.
– Review the medication prior to pregnancy.
Medications and their suitability during pregnancy
Taking into account the above, three groups of drugs can be established depending on their suitability during pregnancy: those that should be avoided during organogenesis, others that can be administered at that stage, and third parties that should not be used under any circumstances. during the nine months of pregnancy:
● Prohibited during organogenesis : Regarding the first group, it is not recommended to consume vitamin A in large doses or hormones such as androgens, anticoagulants or antineoplastics. Once organogenesis has elapsed, there are many antineoplastic drugs, for example, that can be consumed to alleviate neck, ovarian or breast cancer in the case of pregnant women who suffer from it.
● Allowed during organogenesis : A wide variety of antibiotics such as penicillin, ampicillin, amoxicillin, macrolides, and hormones such as natural progesterone or thyroxine can be administered without any risk during organogenesis. In the case of thyroxine, it is in fact essential to administer it whenever necessary since the thyroid must be working perfectly, especially in the sixth or seventh week of gestation.
● Prohibited throughout pregnancy : Finally, there is a third group of drugs that should never be used during pregnancy. For example, women who take ACE inhibitors, prescribed for hypertension, should immediately discontinue them the moment they become healthy . In the same way, depressants such as lithium , which is used for major depressions, or thalidomide , which can cause the lack of limbs in the embryo , must be discarded .
And paracetamol, yes or no? In the specific case of paracetamol, a very frequent question asked by women, most specialists assure that it does not harm the fetus. However, recent studies seem to support an increase in the percentage of childhood asthma in mothers treated with paracetamol in advanced stages of pregnancy.
Effects on the fetus
Although there are multiple studies on the effects of drugs in experimental animals, their conclusions do not have to be exactly the same for humans. The effect of a drug on the fetus will depend on several factors:
– The drug : obviously it will depend on the substance that is administered, the dose we administer and the exposure time.
– From the moment of pregnancy when it is administered : it must be clear that it is not the same to administer a drug in the first period of pregnancy as in the subsequent two. The embryonic period is the most critical when it comes to malformations, since it is at these times when the embryo’s organs are formed.
– Of the maternal state : they predispose in a special way certain maternal diseases such as diabetes, thyroid and liver diseases, placental insufficiency and maternal age. These are diseases that modify the natural behavior of the drug within the body (modify metabolism).
– Fetal susceptibility: not everyone reacts in the same way to the same drug.