The news that Beyonce Knowles gave birth to twins last week barely made headlines in the United States. That's because In vitro fertilization (IVF) multiple births are so commonplace in Hollywood.
Also common is the fact that most stars who give birth to IVF twins opt for a girl and a boy so they don't have to explain why their twins don't resemble each other.
In vitro fertilization is a process by which an egg is fertilized outside of the uterus. The embryo is then implanted in the uterus.
In the case of twins, the parents usually opt for a girl and a boy rather than 2 boys or 2 girls because the twins are not identical.
Multiple birth IVF children rarely resemble each other because the eggs were fertilized by combining eggs and sperm in separate test tubes.
The process is complex and the risk of implantation failure is high. Those factors increase the cost of the IVF procedure, making it out of reach for most couples.
The risk of birth defects with IVF is also much higher than natural births if genetic issues affected the implanted embryos.
IVF children occupy the same uterus and they are born at the same time, but they are technically not twins.
That doesn't stop celebrities such as Mariah Carey and Jennifer Lopez from dressing their IVF children as if they were identical twins.
Expect Beyonce to do the same when she introduces her IVF twins to the world.