It isn't illegal to chew gum, but it is illegal to bring them into Singapore or sell them except for medical purposes. Since you can't buy gum (selling is illegal) there's no way to chew them so it's almost as good as not being able to chew gum. See this: http://www.customs.gov.sg/leftNa...
Definition: In Vitro. A study done in vitro, in contrast, looks at how a drug or procedure responds in the confines of a test tube or laboratory dish. Clinical trials or medical studies may be performed either in vivo or in vitro.
In Vitro Fertilization for Infertility. Guide. During in vitro fertilization (IVF), eggs and sperm are brought together in a laboratory glass dish to allow the sperm to fertilize an egg. With IVF, you can use any combination of your own eggs and sperm and donor eggs and sperm. After IVF, one or more fertilized eggs are placed in the uterus .