3 Gardner D, Schoolcraft W. In vitro culture of the human blastocyst. In: Jansen R, Mortimer D, editors. Towards reproductive certainty: infertility and genetics beyond 1999. Carnforth, UK: Parthenon Publishing; 1999. p. 378-88
Biggers JD, Summers MC Choosing a culture medium: making informed choices. Fertil Steril. 2008 Sep;90(3):473-83. doi: 10.1016/j.fertnstert.2008.08.010. Review.
Gardner DK, Lane M, Calderon I, Leeton J Environment of the preimplantation human embryo in vivo: metabolite analysis of oviduct and uterine fluids and metabolism of cumulus cells. Fertil Steril. 1996 Feb;65(2):349-53.
Gardner DK, Lane M Culture and selection of viable blastocysts: a feasible proposition for human IVF? Hum Reprod Update. 1997 Jul-Aug;3(4):367-82. Review.
Gardner DK, Lane M Culture of viable human blastocysts in defined sequential serum-free media. Hum Reprod. 1998 Jun;13 Suppl 3:148-59; discussion 160. Review.
Summers MC, Biggers JD Chemically defined media and the culture of mammalian preimplantation embryos: historical perspective and current issues. Hum Reprod Update. 2003 Nov-Dec;9(6):557-82. Review.
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.