Frequently Asked Questions (FAQ)

Answers to the questions we hear most often — about finding your size, solving common fit problems, caring for your lingerie, and navigating brand-to-brand sizing differences. For questions about orders, payment, shipping, or returns, see the relevant policy page linked at the bottom.

Finding your size

How do I measure myself for a bra at home?

You need a soft fabric measuring tape — the kind used for sewing, not a metal tape. Take two measurements:

Underbust — directly under the bust, snug against the ribcage. This gives your band size.
Bust — across the fullest part of your chest, while wearing an unlined non-padded bra (or none at all). This gives your cup size when compared to the underbust.

The difference between the two measurements determines your cup letter. A difference of 1 inch is roughly an A cup, 2 inches a B, 3 inches a C, 4 inches a D, 5 inches a DD or E, and so on. The band size is your underbust measurement rounded to the nearest even number (in inches) or to the nearest 5 cm value (in centimeters).

Skip the "+4 method" — the old advice to add 4 inches to your underbust. That method dates from the 1950s, when bra elastic was much less stretchy, and produces bands that are too loose for modern bras. Use your direct underbust measurement.

What is sister sizing and when should I use it?

Sister sizing is the principle that the same cup volume exists across different band-and-cup combinations. The rule is simple: if you go up one band size, go down one cup letter to keep the cup volume the same. If you go down one band size, go up one cup letter. So 34C, 32D, and 36B all hold the same cup volume — they just have different band lengths.

Sister sizing is most useful when the cup of a bra fits well but the band feels too tight or too loose. Instead of jumping a full size, you adjust to a sister size. It's also useful when your usual size is sold out, or when you're moving between brands whose bands fit differently.

Sister sizing is not a substitute for measuring properly. If both the band and the cup feel wrong, the sister size won't help — you need to remeasure.

How do international bra sizes compare?

Bra sizing systems differ between countries. A 34C in the US is roughly a 75C in EU sizing, a 34C in UK sizing (cup letters differ at larger sizes), and an 85C in French sizing. Band measurements use inches in the US and UK and centimeters in continental Europe.

The biggest source of confusion is cup letters at the larger end. UK and most European brands use a continuous DD/E/F/FF/G/GG progression, while US sizing often jumps from DD straight to DDD, then to F or G depending on the brand. A UK FF is a US G in many brands. The Lascava size guide on each product page shows the equivalents for the specific brand you're looking at.

Most women wear the wrong size — how do I know if I'm one of them?

Roughly 70-80% of women wear a bra that doesn't fit correctly, according to most fitting research. The most common pattern is a band that is too loose and a cup that is too small. The signs:

The band rides up your back when you raise your arms
You can pull the band more than a couple of centimeters away from your body
You feel most of the bra's support from the straps, not the band
The cups gap at the top or compress the bust at the sides
The underwire sits on breast tissue rather than against the ribcage

If any of these sound familiar, remeasure with the method above. Many women who think they're a 36C are actually closer to a 32E or 34DD when measured correctly.

Fit problems and solutions

Why does my bra band ride up at the back?

A band that rides up almost always means the band is too loose. The band — not the straps — should provide about 80% of a bra's support, so it needs to sit firmly and horizontally across the back, level with the front. When the band is too loose, the straps end up doing the work, the band lifts, and the cups can pull away from the chest.

The fix is usually to go down one band size and up one cup size — that is, your sister size with a tighter band. So a loose-feeling 36C becomes a 34D.

Why does the cup gape at the top of my bra?

Cup gaping means there's space between the top edge of the cup and your breast tissue. Two common causes:

The cup is too large. Try the same band with a smaller cup letter — for example, 34C instead of 34D.
The cup shape doesn't match your breast shape. Cups with a lot of upper-bust volume (like balconette and demi-cup styles) gape on women whose breasts are fuller at the bottom than at the top. A plunge or full-coverage style with less upper coverage often fits better.

Why is the underwire poking the side of my bust?

Underwire that digs into breast tissue at the sides usually means the cup is too small — the cup can't contain the full breast, so the wire ends up on tissue instead of behind it. Try a larger cup letter, or sister-size up. If the wire pokes at the front center instead, the band may be too loose and shifting forward.

Why do my bra straps keep falling off my shoulders?

Straps that slip can come from a few causes: the straps need tightening (most adjustable straps need re-checking every few weeks as they stretch), the band is too loose (so the bra shifts on your body), or your shoulders slope more than average and benefit from styles with closer-set straps (like full-coverage and balconette cuts, which place the straps more toward the center).

Care and longevity

How should I wash my bras?

Hand washing in cool water is the safest option and meaningfully extends the life of a bra — especially for lace, embroidery, or molded cups. Fill a basin with lukewarm water and a small amount of mild detergent (a wool/silk wash works well), submerge the bra, swirl gently for a minute, and let it soak for up to 20 minutes. Rinse in cool water until the soap is gone, then press out water gently — never wring. Lay flat or hang to dry, away from direct heat or sunlight.

If you machine-wash, hook the bra closed, place it in a mesh laundry bag, choose the delicate or cool cycle, and use mild detergent. Skip the dryer entirely — the heat breaks down elastic and ruins the shape of molded cups.

How often should I wash my lingerie?

Bras don't need to be washed after every wear — every 2-3 wears is normal, unless you've been sweating, exercising, or applied body lotion or perfume directly under them. Rotating between 3-4 bras instead of wearing the same one every day extends the life of each one significantly, because elastic needs roughly 24 hours to recover after a full day of wear.

Underwear is different: wash after every wear, every time.

How should I store my bras?

Stack bras in a drawer with the cups nested inside each other (one cup tucked into the next), not folded. Folding a molded or padded cup permanently creases the shape. If you're short on drawer space, place them flat and side by side, but never fold cups in half.

When should I replace a bra?

A bra typically lasts 6-12 months of regular daily wear before the elastic loses enough strength that the band can no longer give proper support. Signs it's time to replace:

The band feels loose even on the tightest hook
The underwire is poking through the fabric
The straps have stretched and won't stay tightened
The fabric has lost its elasticity or feels limp
The cups have lost their shape or feel stretched out

If your favorite bra is approaching the end of its life, ordering a replacement before the old one fails entirely saves you from going without.

Brands and sizing differences

Why do bras in the same size fit differently between brands?

Each brand uses slightly different cup shapes, wire widths, band elasticity, and grading systems. A 34D from one brand can fit very differently from a 34D in another — even within the same country's sizing system. The most common variations:

Band tightness — some brands run tighter, some looser at the same labeled size
Cup shape — balconette-leaning vs. plunge-leaning vs. full-coverage at the same size
Wire width — narrow wires for centered breasts vs. wide wires for set-apart breasts
Depth — projected cups for full-projection breasts vs. shallow cups

This is why finding your size in one brand doesn't guarantee a perfect fit in another. The size on the label is a starting point, not a guarantee.

How do the brands Lascava carries compare to each other in sizing?

Each brand we work with has its own sizing character. From our experience supplying these brands over the years:

Gorsenia — Polish full-bust specialist. True to EU sizing, with a strong range from D cup upward and band sizes up to 100 (in cm). Generous in cup depth, well-suited to full and very full busts.
Mediolano — Italian-designed, Polish-made. Tends toward elegant fit with moderate cup volume; the band can feel slightly firmer than EU average, so a sister size up is sometimes more comfortable.
Mefemi — Polish brand with a strong everyday range. Standard EU sizing, full-coverage cuts.
Sloggi — Swiss heritage, focused on comfort. Sizing tends to align with EU norms, with seamless and stretch-based fits.
Obsessive — European brand specializing in seductive lingerie. Sizing varies by line — sets often use S/M/L instead of band/cup, which is worth checking against the specific size chart for each piece.

If you're moving between brands or unsure which size to try, email info@lascava.com with your usual size and the brand you're considering. We keep working notes on how the brands we carry compare in practice and can usually suggest a starting size.

Still have a question?

If your question isn't covered here, email info@lascava.com or use our Contact page. We read everything that comes in and try to respond within one business day.

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