Egg Freezing (Oocyte Cryopreservation)

What Egg Freezing Involves

An egg-freezing cycle starts with ovarian stimulation: exogenous hormone medication is given to encourage multiple follicles to develop at once, rather than the single dominant follicle a natural cycle produces.^[1] Follicular growth is monitored by transvaginal ultrasound, with blood estradiol levels used alongside it to gauge how the ovaries are responding and whether the stimulation protocol needs adjusting.^[1]

Once enough follicles are ready, eggs are collected in a retrieval procedure done under sedation: a vaginal ultrasound probe guides a needle into each follicle to aspirate the fluid containing the egg.^[1] The retrieved eggs are then preserved through vitrification, an ultra-rapid freezing technique that has largely replaced older, slower freezing methods.^[3] Because egg freezing preserves eggs rather than attempting a pregnancy, it ends there. Fertilization, embryo development, and transfer only happen later, and only if and when the frozen eggs are used.

What People Track Through the Process

Before and during stimulation, the numbers people watch most closely are markers of ovarian reserve and response: AMH and antral follicle count are typically checked ahead of a cycle, while estradiol is tracked throughout stimulation as follicles grow.^[1] After retrieval, the count that matters is how many eggs came out and how many were mature, the first two figures in what our IVF cycle numbers entry covers in more detail, since an egg-freezing cycle stops there rather than continuing on to fertilization and embryo counts.

How Go Go Gaia Supports Tracking It

Go Go Gaia doesn't provide medical advice about whether or when to freeze eggs. For people already going through it, the app has a standalone egg-freezing journey, separate from its full IVF journey, built around four phases: considering, preparing, in your cycle, and eggs stored. Because it's a preservation journey rather than a pregnancy attempt, it stops after retrieval. There's no fertilization, transfer, or pregnancy-test stage built into it, only the stages that actually apply: pre-treatment, ovarian stimulation, egg retrieval, and a post-cycle check-in.

What the Research Shows

The American Society for Reproductive Medicine's Ethics Committee's 2018 opinion on planned oocyte cryopreservation described it as "an emerging but ethically permissible procedure that may help women avoid future infertility."^[2] A 2024 update reaffirms that it is "an ethically permissible procedure," now describing it as "new and evolving" rather than "emerging" and extending the guidance to "individuals" rather than only women, while still flagging uncertainty around its long-term efficacy.^[4]

StatPearls' overview of in vitro fertilization, which shares its stimulation, monitoring, and retrieval steps with an egg-freezing cycle, describes follicular growth being tracked by ultrasound alongside estradiol levels throughout the stimulation phase.^[1]

A 2022 review in Reproductive Biology and Endocrinology traces the shift in freezing technique from slow-freeze methods to vitrification, an ultra-rapid approach, as a defining development in how retrieved eggs are preserved.^[3]

Related Terms

Frequently Asked Questions

Educational information based on published sources. Not medical advice. For personal concerns, please consult your doctor.

What is egg freezing?

Egg freezing, or oocyte cryopreservation, is a fertility preservation procedure in which eggs are retrieved from the ovaries after a course of hormonal stimulation and then preserved using an ultra-rapid freezing technique called vitrification, for potential future use.^[1][3]

What happens during an egg-freezing cycle?

A cycle involves ovarian stimulation with hormone medication to encourage multiple follicles to develop, monitoring by transvaginal ultrasound and estradiol bloodwork to track that growth, an egg retrieval procedure under sedation, and vitrification of the retrieved eggs for storage.^[1]

Does egg freezing include embryo transfer?

No. Egg freezing stops after retrieval and vitrification. There's no fertilization, embryo transfer, or pregnancy test involved, which is what distinguishes it from a full IVF cycle. Fertilization and transfer only happen later, if and when the frozen eggs are used.^[1]