The hyper-stimulation phase is the first 14 days of a cycle – where rather than grow one egg, the idea is to grow as many eggs as possible. At my age, 10 is good, 15 is solid, 20 fantastic. On average, it takes 9.7 eggs to create one viable embryo worthy of transfer – putting it back inside.
More on these stats later, but the idea right now is “make as many high-quality eggs as possible.” You need two things with IVF: lots of eggs, and good quality eggs. The more of both you have, the better your chances.
It’s all done with shots – mostly sub-cutaneous in belly fat – some in the morning, and some at night.
The shots do a few different things.
Menopur and Follistim are Gonadotropins – natural hormones that stimulate the ovary to promote the maturation of several eggs at once. These shots also contain some follicle stimulating hormone (FSH), a hormone that will stimulate the growth of the follicles themselves. So these shots are doing two things at once: increase the number of follicles, and helping grow the follicles.
Omnitrope is a growth hormone that helps with egg quality.
Those three drugs I take for the first 8 days. On day 6, I add Ganirelix, a Gonadotropin-releasing antagonist – it prevents premature ovulation.
On days 8 – 12, it’s a game of grow the eggs, but watch out to not grow them to fast. Hence the push-pull of the drugs.
Think of the eggs like the runners in a 100-meter dash: all the runners are in the starting blocks for the 3 weeks before starting injections. You want them all to relax in the starting blocks and not do any false-starts. On day 1, the gun goes off – injections start – and the runners start out altogether. You’re giving everyone the gonadotropins to help speed them along. Some of the runners run at exactly the same pace – and some start to spread apart. You don’t want a Usain Bolt in your pack – he gets out too far ahead. You’d give him the Ganirelix to slow him down. You also don’t want anyone lagging far behind. If so, they may not be mature at retrieval – you want them to get across the finish line with everyone else.
By Day 12, the follicles are about 18mm across – about the size of a ping-pong ball. The ones out ahead could be 22-24mm, and the ones that are lagging could be 12mm or smaller. All of these eggs will be retrieved, but the smaller ones may not be mature and won’t hatch. (Yep, that’s what they call it.)
That’s hyper-stimulation in a nutshell. Or, an eggshell, hahah.