Introduction: Based on the perceived risk to newborns and pregnancy outcomes associated with certain drugs, women may be hesitant to prescribe and take drugs during pregnancy. In cases like these, pregnant women may seek treatment using natural health products (NHPs) as alternatives to drugs. Unfortunately, evidence of safety in pregnancy and lactation is unknown for many NHPs. Objectives: To review the present state of evidence on the safety of NHPs during pregnancy and lactation. To create a new system to validate evidence on NHPs during pregnancy and lactation designed to affect medical decision. Methodology: NHPs were systematically reviewed and in some cases, meta-analyzed for evidence of safety during pregnancy and lactation. Results: In total, 79 NHPs were systematically reviewed and 2 NHPs were meta-analyzed in order to determine the evidence of safety in pregnancy and lactation. Despite the presence of data (72/79 NHPs in pregnancy and 53/77 NHPs in lactation), the quality of the data was generally poor. Using evidence-based medicine principles, a new system of evaluating evidence was established for studies involving NHPs in pregnancy and lactation. A number of NHPs were identified as being of potential risk in pregnancy. A number of NHPs were identified as potentially being apparently safe in pregnancy and lactation. Blue cohosh is of potential concern for harm in pregnancy given an apparent dose-dependant relationship. Conclusion: There is a large knowledge gap on the safety of NHPs in pregnancy, even more so in lactation. The new system for evaluating NHP safety in pregnancy and lactation will require validation. In order to improve the knowledge gap, future studies are proposed on NHPs in pregnancy and lactation as part of the newly formed MotherNature research network.

Introduction: Based on the perceived risk to newborns and pregnancy outcomes associated with certain drugs, women may be hesitant to prescribe and take drugs during pregnancy. In cases like these, pregnant women may seek treatment using natural health products (NHPs) as alternatives to drugs. Unfortunately, evidence of safety in pregnancy and lactation is unknown for many NHPs. Objectives: To review the present state of evidence on the safety of NHPs during pregnancy and lactation. To create a new system to validate evidence on NHPs during pregnancy and lactation designed to affect medical decision. Methodology: NHPs were systematically reviewed and in some cases, meta-analyzed for evidence of safety during pregnancy and lactation. Results: In total, 79 NHPs were systematically reviewed and 2 NHPs were meta-analyzed in order to determine the evidence of safety in pregnancy and lactation. Despite the presence of data (72/79 NHPs in pregnancy and 53/77 NHPs in lactation), the quality of the data was generally poor. Using evidence-based medicine principles, a new system of evaluating evidence was established for studies involving NHPs in pregnancy and lactation. A number of NHPs were identified as being of potential risk in pregnancy. A number of NHPs were identified as potentially being apparently safe in pregnancy and lactation. Blue cohosh is of potential concern for harm in pregnancy given an apparent dose-dependant relationship. Conclusion: There is a large knowledge gap on the safety of NHPs in pregnancy, even more so in lactation. The new system for evaluating NHP safety in pregnancy and lactation will require validation. In order to improve the knowledge gap, future studies are proposed on NHPs in pregnancy and lactation as part of the newly formed MotherNature research network.