Pregnancy, obstetrics and lactation

Medicines for pregnant and breastfeeding women

Pregnant and breastfeeding women and their unborn or breastfed children make up a group of patients who are particularly sensitive and at the same time heterogeneous. During pregnancy a large number of physiological adjustments can lead to changes in the efficacy of certain medicines. Some active substances are distributed, degraded or excreted differently by the body, i.e. their pharmacokinetics is modified and accordingly their action (pharmacodynamics) may be modified too.

This means that the dosage of medicines has to be modified during pregnancy and in some cases also during the period after birth - under certain circumstances repeatedly.

When treating pregnant or breastfeeding women there is also always the question of whether medication represents a risk to the unborn child or breastfed infant. There are medicines that can disrupt or impair organ formation, development and growth in the child while it is still in the womb and after birth. These and other aspects must be borne in mind when prescribing and dispensing medicines to pregnant and breastfeeding women.

Off-label-use for pregnant or breastfeeding women

A medicine can only be officially authorised for use by pregnant and breastfeeding women if clinical trials have been performed with the corresponding female patients and reviewed during the authorisation process. With a few exceptions, medicines have not been developed or authorised for this category of patients, and for this reason they are often used "off-label", i.e. outside the indications listed in the approved information about the medicine. This is permitted by the Therapeutic Products Act provided the recognised rules of medical and pharmaceutical science are observed.

There are many and varied reasons why relatively little has been invested in research and development relating to the treatment of diseases during pregnancy and lactation. One is the complex situation created by the changing physiology of women who require treatment during pregnancy and while breastfeeding; another is the vulnerability and limited size of the group of patients. Trials need to be designed in such a way that they observe all the individuals involved (pregnant or breastfeeding women, their children) for as long a period as possible. In pharmacokinetic studies all the compartments (mother’s blood, child’s blood, mother’s milk) have to be taken into account in order to determine the distribution and degradation of the active substances during all phases of pregnancy and during lactation – and thus an appropriate dosage.

This situation is also reflected in the information for healthcare professionals; it often does not pay due attention to pregnant and breastfeeding women, or the information provided contains few precise details. Many medicines that are used on a daily basis by pregnant women on an off-label basis have been on the market for decades. Yet publications in scientific journals frequently contain little information about this patient category.

Interdisciplinary Network Medicine and Pharmacy

The problem was identified and in some cases described by a number of experts some time ago. They joined forces in a network of the Swiss Association of Perinatal Pharmacology (SAPP) to compile the available data in the literature and draw up evidence-based guidelines for using medicines during pregnancy and lactation.

The focus here is on evaluating and publishing the available evidence-based data for medicines that are used daily without the corresponding authorisation for this group of patients. This does not change the status of “off-label use” for these medicines, but it does enable them to be used more safely.

Reports of adverse effects in mother and (unborn) child

Suspected adverse effects must be reported to Swissmedic in the interest of the safe use of medicines and continuous improvement of the information for healthcare professionals. Reports should be made electronically using the specially developed reporting platform ElViS.

In Switzerland the Swiss Teratogen Information Service (STIS) in Lausanne provides advice to healthcare professionals on the use of medicines during pregnancy and lactation. The STIS also collects reports on the use of medicines during pregnancy that could harm the unborn child and evaluates them.

Last modification 05.12.2017

Top of page