So the reason why women have a greater chance of miscarriage as they age is because all the eggs that they're ever going to have are there when they're born. So unfortunately, as we age, the eggs age. It's different for men, they actually produce new sperm every day and that's why it's not important, the age of a male, to determine their fertility. But for us, when an egg is getting ready to divide in an effort to get ready for that sperm to come in and meet it, what happens when the egg has been around for a while, for lack of a better term, the chromosomes get sticky. And essentially when the egg divides, getting ready for that sperm to come and meet the egg, it might hang onto an extra chromosome or it might let go of an extra chromosome. So what ends up happening is, instead of you just having one chromosome 21, you hang onto an extra one and then you have two. And when the sperm into join it, you have three. And that's what results in a trisomy 21 or a down syndrome. But it also might be chromosome number two, and so if you have an abnormal amount of chromosome number two, and then the sperm comes in and meets it you either have only one or you might have three. And that might be an embryo that either doesn't implant, if it implants can lead to a miscarriage, or can be something that might be viable but then has difficulties later on. So the reason why women have an increased risk of miscarriage as they age is because they have an increased risk of having a chromosomal abnormality in the embryo, because the eggs just don't divide as they should.