The 45:55 Breast Proportion Guideline

The 45:55 breast ratio is an aesthetic guideline often referenced in breast surgery when considering your breast implant size.. It suggests that a natural-looking breast may have approximately 45% of its volume above the nipple (upper pole) and 55% below (lower pole).

• Upper pole (45%) – a gentle slope above the nipple
• Lower pole (55%) – slightly fuller to create a natural contour

This concept, based on work by Dr Tony Prochazka is used as a visual guide rather than a fixed rule when considering your breast implant size, helping to achieve a balanced and proportionate result.

Breast Implant Size Is More Than Volume

Breast Implant size is often measured in cubic centimetres (cc), but choosing the right size is not simply about selecting a number.

Factors that influence implant size include:

• Your natural breast tissue and chest width
• Your height and overall body proportions
• Skin elasticity and breast shape
• Your lifestyle and activity level
• Your personal aesthetic preferences

Dr Tony Prochazka will consider all of these factors when helping you choose a size that complements your body.

The final result is also influenced by how implants are positioned. You can learn more about this in our guide to Implant Placement Options.

Implant Profile and Shape

In addition to the breast impalnt size, the implant profile affects how your breasts will look.

• Low profile – wider, more subtle projection
• Moderate profile – balanced projection and width
• High profile – more projection with a narrower base

Profile selection works together with size to achieve your desired outcome.

Setting Realistic Expectations

Every patient’s anatomy is different, and results vary between individuals. During consultation, your surgeon will discuss what may be achievable and guide you towards a suitable option.

You may also wish to read about Recovery After Breast Implants when planning your procedure.

Book a Consultation

We welcome your enquiry to book an appointment to discuss your breast implant options with one of our Doctors. This is best done by calling, texting or email.
You can call or text 0409149521

However, if you are early in your research and would like information, we invite you to book a complimentary consultation with our patient care team.
They will take the time to understand your concerns and guide you through your options — without pressure or obligation.

We welcome your enquiry.