Headaches associated with marijuana withdrawal can last for a few weeks up to a couple of months. Headaches, like most other symptoms of withdrawing from marijuana use, will usually begin one to three days after quitting and will peak two to six days after stopping.
fertilization - creation by the physical union of male and female gametes; of sperm and ova in an animal or pollen and ovule in a plant. fecundation, fertilisation, impregnation. conception, creation - the event that occurred at the beginning of something; from its creation the plan was doomed to failure.
In Vitro Fertilization. In Vitro Fertilization (IVF) is the process of creating embryos from oocytes (unfertilized egg cells) by fertilizing them with semen in a Petri dish.