SO, YOU WANT TO FREEZE YOUR EGGS…

STEP 1: Meet with your doctor to discuss your medical history.

STEP 2: You’ll have an ultrasound of your ovaries and some blood tests to determine your “ovarian reserve.” (That’s the number of eggs being used each month in order for you to ovulate one egg.) The ultrasound measures your antral follicle count, which is the number of immature eggs that are primed to grow. These primed follicles are called antral follicles. Many antral follicles are wasted each month to allow you to ovulate. The size of that group reflects how many of your eggs might be extracted during an egg retrieval. The anti-Müllerian hormone is a blood test that measures the hormone associated with the growth of antral follicles. On average, most women will have two to four clinic visits during this step.

STEP 3: You’ll begin daily follicle stimulating hormone injections for up to two weeks to “rescue” the antral follicles that were going to be wasted that month. (That means your ovaries will produce multiple mature eggs in one menstrual cycle instead of the single egg they would typically release.) During this step, you’ll have earlymorning blood work and transvaginal ultrasounds to assess how your ovaries are responding to the hormones.

STEP 4: When the time is right, you will be instructed to give yourself a trigger injection—the final timesensitive injection before your eggs are collected some 36 hours later. STEP 5: Egg retrieval time! You’ll be given conscious sedation, and the doctor will use an ultrasound-guided procedure to retrieve eggs from your ovaries. The procedure takes 15 to 20 minutes.

STEP 6: Your mature eggs will be bathed in cryoprotectants—substances that draw water out of the eggs in order to reduce the risk of ice crystals forming when they’re being frozen. This is critical because crystals can damage the eggs. Your eggs will then be stored in straws and dipped in liquid nitrogen so they freeze almost instantly, before crystals can start to form.

STEP 7: When you’re ready to attempt to get pregnant, your eggs will be thawed; each one will be injected with a single sperm before being transferred to your uterus as an embryo. The success rate using frozen eggs appears to be similar to that of in vitro fertilization. For women aged 38 to 40, there’s a 22 per cent chance of success, and by age 43, this drops to 5 per cent, but the success rate varies depending on the woman’s age, the clinic and the individual.