Since 1997
How to select silicone breast forms for your frame and size starts with accurate measurements and understanding your body’s needs. To select silicone breast forms, begin by measuring your bra band and cup size using your current body measurements, not your pre-surgery size. Next, consider your surgery type, such as unilateral mastectomy, bilateral mastectomy, or lumpectomy, because this affects how you measure and which form shape fits best. Then, use the manufacturer’s size chart to find your correct form number. Also, consider your shoulder and chest width when assessing overall proportion and balance. Finally, a certified mastectomy fitter can confirm your size and shape in a single appointment, so you can feel confident about fit and comfort.
Key Takeaways
• Your bra size and your breast form size are not the same thing. Always take fresh measurements; never rely on your pre-surgery size.
• How you measure depends on your surgery type. Bilateral, unilateral, and lumpectomy patients each follow a slightly different approach.
• Shape matters as much as size. The wrong shape for your surgery type will not feel right, regardless of the number on the chart.
• Body frame (shoulder width, chest width, height) affects what looks and feels proportional on your body.
• A certified mastectomy fitter can confirm your size and shape in a single appointment, and many insurance plans cover the breast forms themselves. See our post-surgical fittings for details.
Why Silicone Breast Forms, and Why Sizing Matters So Much
Silicone breast forms closely replicate the weight, warmth, and movement of natural breast tissue. That is why they feel more natural under clothing than foam or fiberfill alternatives, especially once your surgical site has healed.
The weight-matching matters most. A form that is too light will not balance with natural tissue on the other side. Over time, that imbalance creates strain on the neck and shoulders.
A form that is too large feels uncomfortable and shifts throughout the day. A form that is too small does not restore symmetry or confidence. Getting the size right the first time saves money, frustration, and unnecessary returns. A professional fitting is always worth it.
First, Know Your Surgery Type: It Changes How You Measure
This is the step most sizing guides skip. Whether you had a unilateral mastectomy, a bilateral mastectomy, or a lumpectomy changes both how you take your measurements and which form type you need. Use this section as your decision point before anything else.
Measuring for a Unilateral Mastectomy
You have one natural breast to use as a reference point. The goal is to find a form that mirrors it in projection, height, and width.
- Band size: Wrap a soft fabric tape measure around your torso, directly under your bust, where a bra band sits. Keep the tape snug and level with the floor all the way around. If the number is odd, round up to the closest even number.
- Cup size: Measure over the fullest part of your remaining breast. Deduct your band measurement from this number. Each inch of difference typically corresponds to a cup size (1 inch = A, 2 inches = B, 3 inches = C, and so on).
- Match to your remaining breast: The goal is symmetry, same projection, same height placement, same base width.
Note: Do not measure while wearing a padded or molded cup bra. It will distort your cup reading.
Measuring for a Bilateral Mastectomy
There is no remaining tissue to mirror, so cup size is based on your preference, body frame, and what feels proportional.
- Band size: Measure the same way, around your torso just under where the bust line is. Keep the tape level.
- Cup size: Look at pre-surgery photos as a starting point. Consider whether you want to match your previous size, go slightly smaller for everyday comfort, or choose based on your current lifestyle.
- Starting smaller is almost always recommended for first-time wearers. You can size up once you are comfortable with the weight and feel.
A certified mastectomy fitter can help you try several sizes in a private, supported appointment to find what works best for your frame.
Sizing for a Lumpectomy: When a Full Form Is Not the Answer
A lumpectomy removes part of the breast tissue, not the entire breast. The remaining tissue still shapes how you look and feel, which means a full-size prosthesis is usually not appropriate here.
- Partial forms, shapers, or enhancers are designed to fill in the area where tissue was removed and restore symmetry without replacing the whole breast.
- The right partial form size depends on how much tissue was removed and where. A certified fitter can assess this precisely after examining the area.
- Some lumpectomy patients find that a lightly padded mastectomy bra achieves the symmetry they need without any insert at all.
How Body Frame Affects Your Breast Form Size
Every guide mentions body frame. Almost none explain what it actually means in practice. Here is what matters.
Shoulder width is the most overlooked factor. A form that extends too wide for your shoulder line will feel like it is slipping outward. One that is too narrow will look unnatural in clothing and create a gap at the sides of the bra cup.
Chest width is just as important. The base width of the form should match the width of the chest wall where the breast naturally sits. A form with a base that is too wide or too narrow on the chest wall will not stay comfortable over a full day.
Height and overall build also play a role. Women with a petite frame often find that a form one cup size smaller than their pre-surgery size looks more proportional. Women with a taller or larger build may find their measured size is accurate or even slightly undersized.
Practical test: If your bra straps are constantly slipping or the form feels like it is pulling to one side, the base width of the form is likely the problem, not the cup size. Adjust base width before changing cup size.
Breast Form Shapes: Which One Is Right for Your Surgery?
Shape is not optional. Choosing the right shape for your surgery type is as important as choosing the right size.
Symmetrical Forms: The Most Versatile Starting Point
Symmetrical forms can be worn on either the left or right breast. This makes them the most flexible option for standard mastectomy cases where no tissue was removed from the upper chest or underarm area.
- Triangle profiles: suit women with firmer chest muscles. They give a lifted, projected appearance and sit well under structured clothing.
- Teardrop profiles: fuller at the bottom, with a natural drape. They suit women who prefer a softer, more relaxed silhouette under everyday clothing.
Asymmetrical Forms: For Extended Surgery or Underarm Involvement
Asymmetrical forms are designed specifically for either the left or right side. They cannot be swapped between sides.
- They include an extended wing or tail on one side to fill the area under the arm and near the collarbone where tissue or lymph nodes have been removed.
- Best for: women who had a radical mastectomy or had significant tissue removed from the axillary (underarm) area.
- If you notice a hollow or depression near your underarm after a standard mastectomy, an asymmetrical form may provide better coverage than a symmetrical one, even if that was not your original surgery type.
Partial Forms and Shapers: For Lumpectomy and Partial Tissue Loss
Partial forms fill in an area of tissue loss rather than replacing the entire breast. They are far lighter than full silicone forms and much less intrusive.
- They come in various thicknesses and profiles to match different degrees of tissue removal.
- Best for: lumpectomy patients, women after partial mastectomy, or women who want to add subtle volume or symmetry without committing to a full prosthesis.
- Many women new to any kind of insert start with partial forms because the transition is gentler, both physically and emotionally.
Using a Breast Form Size Chart
Here is the most important thing to know before you open any size chart: your bra size and your breast form size are not the same number.
Breast forms use their own numeric or letter-based sizing system (such as Size 1, 2, 3 or XS, S, M) that varies by manufacturer. Reading the chart is straightforward once you have your measurements.
- Take your band measurement and cup size from the measurement steps in the surgery type section above.
- Find your band size in the left column of the manufacturer’s size chart.
- Slide across to the column for your desired cup size. The number or letter where they intersect is your breast form size.
Example: A band measurement of 34 with a B cup typically corresponds to a size 4 on most standard charts. This varies by brand, so always use the specific manufacturer’s chart for the product you are buying.
Between sizes? Choose the larger size for more natural projection, or the smaller for a lighter, more discreet feel. Our certified fitters at A Fitting Experience can help you test both in a private appointment. Visit our post-surgical fittings page to learn more.
How to Select Silicone Breast Forms for Your Frame and Size Correctly
Women wearing the wrong size often do not realize it right away. They just feel discomfort, fatigue, or self-consciousness and give up. Here is what to look for.
| Signs of a Good Fit | Signs of a Poor Fit |
|---|---|
| The form sits flush against your chest wall without gaps at the edges | Edges lift away from the chest, especially at the top or sides |
| Your bra neckline and side seams lie flat | Bra cups gap, overflow, or pull in one direction |
| The form stays in place through a full day of activity | The form shifts forward, sideways, or downward by midday |
| Your silhouette looks symmetrical in clothing | One side appears visibly higher, lower, or fuller than the other |
| No shoulder or neck ache after wearing for several hours | Bra straps dig in, or you feel neck strain by the afternoon |
If you recognize several of the poor fit signs, do not adjust your bra straps first. The issue is almost always base width or depth of the form, not the straps. Review our breast form FAQs or schedule a re-fitting appointment.
When to Start Wearing Breast Forms, and What to Wear First
Timing matters. Moving too quickly to a heavier silicone form before the surgical site is ready can cause discomfort and slow healing.
- Immediately after surgery, most surgeons recommend foam or fiberfill forms as a first step. They are lightweight, place no pressure on the surgical site, and help you get used to the look and feel of a prosthesis without physical strain.
- Silicone breast forms: typically appropriate 6 to 8 weeks after surgery, once the surgical site is fully healed and closed. Always follow your surgeon’s specific guidance. If you had radiation treatment, the skin may need additional healing time before silicone contact is comfortable.
- The transition from foam to silicone is a milestone many women look forward to. Silicone forms feel significantly more natural and closely match the weight and warmth of breast tissue.
- Wait until you are comfortable standing and moving freely before your first silicone fitting. You want to be able to assess comfort and balance properly, not just how the form looks in a mirror.
The Easiest Way to Get Your Sizing Right: A Professional Fitting
An ABC-certified mastectomy fitter does more than take your measurements. They assess your chest wall profile, your surgery type, your lifestyle, and your clothing preferences to recommend the right form, shape, and size combination.
A professional fitting typically includes: measurements at multiple points, testing several form options in a private fitting room, bra fit assessment, and placement guidance so you leave knowing exactly how to put the form in and take it out.
- A Fitting Experience Mastectomy Shoppe has been providing certified fittings since 1997. Our team understands the full range of post-mastectomy situations, from first-time form wearers to women switching from foam to silicone for the first time.
- For women whose standard form sizes do not provide the right fit due to an unusual chest wall shape, asymmetric scarring, or a specific reconstruction outcome, custom-made breast forms can be designed to match their exact body, skin tone, and silhouette.
- Many insurance plans cover breast forms under the Women’s Health and Cancer Rights Act. Our team can help you understand your benefits and assist with paperwork. See our insurance coverage guidance page for more information.
Frequently Asked Questions
What size breast forms should I get?
Start by measuring your band size (underbust) and your cup size, using your current measurements rather than your pre-surgery size. Match those numbers against the manufacturer’s size chart for the specific brand you are considering. If you are unsure or fall between sizes, a certified fitter can test both in a private appointment.
Is a breast form size the same as my bra size?
No. Breast forms use their own numeric or letter-based sizing system that varies by manufacturer. A 34B bra does not automatically mean a specific form number; you need to consult each brand’s individual size chart. Our team can walk you through this during a fitting.
What is the difference between symmetrical and asymmetrical breast forms?
Symmetrical forms can be worn on either side and are best for standard mastectomy cases. Asymmetrical forms are designed for one specific side and include an extended wing to fill tissue loss near the underarm or collarbone, typically after a radical or axillary-involved mastectomy.
How long after a mastectomy can I start wearing silicone breast forms?
Most surgeons recommend waiting 6 to 8 weeks after surgery, once the surgical site is fully healed and closed. During recovery, a lightweight foam or fiberfill form is the safer option. If you had radiation treatment, additional healing time may be needed before silicone contact is comfortable. Always follow your surgeon’s specific guidance.
How do I know if my breast form is the right size?
A well-fitting form sits flush against the chest wall, stays in place through a full day of activity, and keeps your silhouette symmetrical in clothing. If edges lift away from the chest, the bra pulls to one side, or you notice neck and shoulder ache by midday, the base width or depth of the form is likely off. A re-fitting appointment is the quickest fix.
Can insurance cover breast forms?
Many insurance plans, including Medicare, cover breast prostheses under the Women’s Health and Cancer Rights Act. Coverage depends on your specific plan, documentation from your surgeon, and other factors. We cannot guarantee coverage, but our team can help you understand your benefit and navigate the paperwork. See our insurance coverage page or visit our testimonials page to read about other patients’ experiences.
Ready to Find Your Right Fit?
If you or someone you love is recovering from breast surgery and needs help choosing breast forms, mastectomy bras, compression garments, or other post-surgical products, A Fitting Experience can help.
Schedule a private in-person or virtual fitting with our certified fitters.
Call us: (954) 978-8287 | Request an appointment: Contact Us