The new guidelines - brought into force because of coronavirus disruption - also apply to frozen sperm and embryos.
The singer suffers from a condition called endometriosis, which affects approximately 10% of women worldwide.
Men who drank alcohol three months before conception had a 44% raised risk of the baby being born with congenital heart disease.
"For everyone going through infertility and conception hell, please know it was not a straight line to either of my pregnancies."
Enabling couples who cannot conceive naturally to have babies via artificial fertilisation is altering human evolution, a leading fertility researcher has claimed. In-vitro fertilisation (IVF) could alter the human genome by allowing defective genes that would normally die with the carrier to be passed onto future generations, according to Dr Hans Hanevik, who leads the fertility department at Norway's Telemark Hospital. Millions of babies born through IVF are likely to carry the genes that caused their parents’ fertility problems, meaning they might also need artificial help to conceive when they are eventually ready to have children.