Tamiflu® and Relenza® pregnancy registry.
Influenza A H1N1 : antiviral treatments
Available data
Published data regarding exposure to oseltamivir (Tamiflu®) or zanamivir (Relenza®) in the first trimester of pregnancy are scarce, and virtually inexistent during the second and third trimesters. However, no disturbing outcome has to date been raised from these observations. In addition, these antiviral agents were not shown to be teratogenic or foetotoxic in animal studies. Use of Tamiflu® or Relenza® can be contemplated during pregnancy on a case to case basis, after individual risk-benefit evaluation by a physician. From these data, we also expect no significant increase in the basal risk of malformations, foetotoxicity or obstetrical complications in the case of a fortuitous exposure to these antiviral treatments (unknown pregnancy). But the limited number of human exposures remains to date insufficient to express firm conclusions regarding the safety of oseltamivir or zanimivir use during pregnancy. It is therefore encouraged that prescribers notify all new exposures, including those without noticeable adverse events or complications.
Notification of exposure to Tamiflu® or Relenza® without complication in pregnant women 
Tamiflu® and Relenza® pregnancy registry
In the current influenza A H1N1 flu pandemic situation, the STIS in collaboration with Swissmedic has set up a Swiss pregnancy registry of exposures to Tamiflu® or Relenza®, aimed to improve our knowledge regarding these drugs.
What is the aim of the Tamiflu® and Relenza® pregnancy registry?
Currently available observations are insufficient to firmly ascertain the safe use of these drugs during pregnancy. This prospective survey, conducted on a voluntary basis, is aimed to collect, assess and report on the course and outcome of pregnancies exposed to Tamiflu® or Relenza®.
Why should I include my patient in this registry?
Participation in this registry will contribute to acquire relevant safety data concerning the use of Tamiflu® or Relenza® during pregnancy. The information collected will help in answering questions from healthcare professionals and in counseling future patients regarding the use of these drugs during pregnancy to the best of our knowledge.
How can I participate in this pregnancy registry?
Notifications of exposure to Tamiflu® or Relenza® can be sent to us at any stage of pregnancy, including cases where the antiviral treatment was prescribed prior to awareness of pregnancy.
We invite you to notify all cases of exposure to Tamiflu® or Relenza® in pregnant women by downloading and filling out the form intended for the notification of drug exposure in pregnancy. The form is to sent by post mail, fax or e-mail to:
Swiss Teratogen Inforamation Service STIS
Division de pharmacologie et toxicologie cliniques
Hôpital de Beaumont 6ème étage
1011 Lausanne CHUV
Fax : 021.314.42.66
Information requested under each heading of this form is necessary to determine whether the pregnancy outcome might bare any relation with drug exposure. It is notably essential for us to receive information regarding:
- Name and address of the notifying healthcare professional, to complete information concerning the course of pregnancy, its outcome, as well as fetal and neonatal health status.
- At least the initials and birth date of the mother, which will allow for identification and gathering of follow-up data at the expected time of delivery.
- Indication for antiviral treatment (prophylaxis or therapy)
- Patient co-morbidities and co-medications
Please pay attention to the confidentiality clause, inform the patient of her inclusion and make sure of her approval.
Upon receiving your notification, we will address you a follow-up form which will allow us to collect information concerning the course of the pregnancy, delivery and neonatal health status. We would be grateful if you return this form at the time of delivery or of any other pregnancy outcome.
Notification of adverse events during pregnancy
According to the legislation, healthcare professionals are required to notify clinically relevant adverse events occurring in patients taking Tamiflu® or Relenza®. This is done using the form intended for notification of suspected drug adverse events elaborated by Swissmedic. This form can be downloaded from the Swissmedic internet site (www.swissmedic.ch) or can be found annexed to the Swiss Physician’s Desk Reference (Compendium Suisse des Medicaments).
In the case of an adverse event occurring in a pregnant women, we invite you to send this form by post mail, fax or e-mail to:
Swiss Teratogen Inforamation Service STIS
Division de pharmacologie et toxicologie cliniques
Hôpital de Beaumont 6ème étage
1011 Lausanne CHUV
Fax : 021.314.42.66