A recent study looked into the dose of FSH (a follicle stimulating hormone) given during IVF to see if it affects the number of eggs or the number of embryos.
At the start of the IVF process, gonadotrophins are used. Gonadotropins are hormones that stimulate the growth of more than one egg, so multiple eggs can be extracted to create embryos. Many of these embryos are genetically abnormal and not able to progress to a live birth.
It is generally believed that if you increase the dosage of gonadotropins, it will increase the number of eggs and the number of embryos that can be used to transfer. However, it is not certain if high doses of gonadotrophin are associated with an increased risk of genetic abnormalities in the eggs and embryos.
The STREAM study found that increasing the dosage from 150 to 300 does not increase the number of eggs that can be extracted or the number of embryos that can be transferred. A dose of 300 is reasonably safe for hormone injections in IVF.