Does wearing a small sports bra cause breast sagging?

After breast augmentation I find no particular advantage to the use of surgical bras. In fact, I find that they can do more harm than good. They hold the implants too high, preventing them from dropping into position. In addition, they can put pressure on the healing breast or the wound. They provide no advantage. If the surgery was performed correctly, external appliances after surgery are unnecessary to achieve the appropriate final implant position. At one month we allow the patients to wear a soft cup bra with no underwire.  At two months, they can wear any bra with a wire without push up.  Before three months it is not wise to buy a whole new set of bras.  By six months, the bra size is not going to change.  You need to try bras on.  Being measured is almost never productive and almost always oversizes.  Find the ones that you like the way they fit.

Thank you for your question. Wearing a smaller sports bra shouldn't cause sagging or stretch marks to your breasts.  

Dear xoxochristie,
smaller bra should have no effect on breasts sagging. In most cases, pregnancy, breastfeeding, weight fluctuations can cause sagging. 
Daniel Barrett, MD
Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery