AIM: To undertake an observational study of the number of medicines related queries received by QMAIS (Queensland Medicines Advice and Information Service) regarding the use of medicines in the pre and post-natal period. METHOD: A sample of queries from January to July 2015 was reviewed to identify the number and types of pregnancy, lactation and fertility questions received by QMAIS. A further sub-analysis was conducted on psychotropic, immunosuppressive and antiepileptic medicines. The ANDIN (Australian National Drug Information Network) program was used by QMAIS to record and retrieve this data. RESULTS: A total of 1222 queries were answered in this period. Approximately ninety-eight (98%) were answered within the requested time. Approximately one quarter of the questions were related to pregnancy or lactation. There was just over 1% related to fertility/ infertility. Twenty-six (26%), 8% and 6% of the pregnancy and lactation queries were related to psychotropic, immunosuppressive and antiepileptic medicines respectively. QMAIS is involved in providing and interpreting information to specialists about the safety of medications used in their complex and chronically ill patients during pregnancy and lactation and two of these cases will be discussed. CONCLUSION: This study has shown that QMAIS provides a comprehensive information service to all health care professionals in Queensland regarding complex pregnancy and lactation queries.