Emergency contraceptive pill safety profile. Comparison of the results of a follow-up study to those coming from spontaneous reporting

Pharmacoepidemiol Drug Saf. 2015 Jan;24(1):93-7. doi: 10.1002/pds.3725. Epub 2014 Nov 18.

Abstract

Background: The emergency contraceptive pill (ECP) containing levonorgestrel is dispensed without a prescription in Spain since 2009. An easy access could diminish unwanted pregnancies; however, there is a risk of misuse and, in any case, of developing some adverse events. The aim of the present study is to further learn the adverse effects of this ECP.

Methods: An ad hoc follow-up study was carried out in three community pharmacies in a city of Central Spain; the sample was composed of those women asking for the ECP; they were interviewed by telephone after at least a month since the last menses. We completed the safety profile obtained with that coming from spontaneous reporting in Spain.

Results: Out of 139 women surveyed, 113 developed any adverse event--two considered as severe; the most frequently reported events were menstrual disturbances, which accounted for 21% of all events. Through spontaneous reporting, 36 cases of whatever adverse events related to levonorgestrel as ECP were identified. Twenty-five cases were considered as severe. Both types of reaction and severity were significantly different in the follow-up study and in the spontaneous reporting. Some of the reactions identified, such as miscarriage, febrile neutropenia, and porphyria, are not included in the Summary of Product Characteristics.

Conclusions: Levonorgestrel as an ECP is mostly safe. Attention should be paid to some severe events and particularly to those risk factors for them to appear. Combining spontaneous reporting with an ad hoc follow-up study, the whole safety profile of a given medication can be obtained.

Keywords: ADR spontaneous reporting; adverse events; emergency contraceptive pill (ECP); follow-up study; pharmacoepidemiology.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Contraceptives, Postcoital / administration & dosage
  • Contraceptives, Postcoital / adverse effects*
  • Data Collection / standards*
  • Drug-Related Side Effects and Adverse Reactions / epidemiology
  • Female
  • Follow-Up Studies
  • Gastrointestinal Diseases / chemically induced
  • Gastrointestinal Diseases / epidemiology
  • Humans
  • Menstruation Disturbances / chemically induced
  • Menstruation Disturbances / epidemiology
  • Middle Aged
  • Self Report / standards*
  • Young Adult

Substances

  • Contraceptives, Postcoital