USE OF PRIMODOS AND HORMONAL PREGNANCY TESTS IN PREGNANCY

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(Date of issue: April 2020, Version: 3)

This is a UKTIS monograph for use by health care professionals. For case-specific advice please contact UKTIS on 0344 892 0909. To report an exposure please download and complete a pregnancy reporting form. Please encourage all women to complete an online reporting form.

A corresponding patient information leaflet on Primodos use in pregnancy is available at www.medicinesinpregnancy.org.

Summary

An Expert Working Group (EWG) of the UK’s Commission on Human Medicines (CHM) has published their report on the use of hormone pregnancy tests (HPTs) and adverse effects relating to pregnancy including possible birth defects. Please click here for further information.

Primodos (10mg norethisterone acetate + 0.02mg ethinyloestradiol) was used as an oral hormonal pregnancy test from 1953 to 1975. Concern was raised in the mid-1960’s regarding a possible increase in congenital malformations in infants exposed in utero to Primodos and other oral hormonal pregnancy tests. As a consequence of the introduction of urine-based pregnancy tests and the withdrawal of Primodos from the market, pregnancy safety data are limited.

Although some studies have suggested a possible association between Primodos exposure and increased rates of specific congenital malformations, the more methodologically robust prospective controlled studies have not provide evidence of such. Similarly, the methodologically limited data relating to oral hormonal pregnancy tests as a group do not conclusively provide evidence of an increased risk of malformation or specific pattern of malformation in exposed fetuses.

Referral to a clinical geneticist is recommended in all cases where a causal association between a congenital malformation and in utero exposure to an oral hormonal pregnancy test is being questioned, as identification of an underlying genetic cause may have implications in terms of recurrence risk for the individual and other members of the family.

This document is regularly reviewed and updated. Only use UKTIS monographs downloaded directly from TOXBASE.org or UKTIS.org to be sure you are using the most up-to-date version.

This is a summary of the full UKTIS monograph for health care professionals and should not be used in isolation. The full UKTIS monograph and access to any hyperlinked related documents is available to health care professionals at www.toxbase.org.

If you have a patient with exposure to a drug or chemical and require assistance in making a patient-specific risk assessment, please telephone UKTIS on 0344 892 0909 to discuss the case with a teratology specialist.

If you would like to report a pregnancy to UKTIS please click here to download our pregnancy reporting form. Please encourage all women to complete an online reporting form.

Disclaimer: Every effort has been made to ensure that this monograph was accurate and up-to-date at the time of writing, however it cannot cover every eventuality and the information providers cannot be held responsible for any adverse outcomes of the measures recommended. The final decision regarding which treatment is used for an individual patient remains the clinical responsibility of the prescriber. This material may be freely reproduced for education and not for profit purposes within the UK National Health Service, however no linking to this website or reproduction by or for commercial organisations is permitted without the express written permission of this service. This document is regularly reviewed and updated. Only use UKTIS monographs downloaded directly from TOXBASE.org or UKTIS.org to ensure you are using the most up-to-date version.