Supple Cups have been designed to help address flat, shy and inverted nipples, which collectively affects 28-35% of women who are pregnant for the first time. *Supple Cups are clinically proven: The Use of Supple Cups for Flat, Retracting, and Inverted Nipples, Julie Bouchet-Horwitz, Clinical Lactation, Volume 2, Number 3, 2011, pp. 30-33(4). Supple Cups have been recommended by many leading lactation experts in the following books: i. Selecting and Using Breastfeeding Tools ii. Counseling The Nursing Mother: A Lactation Consultant's Guide iii. Breastfeeding And Human Lactation iv. Northwest Natural Childbirth v. Supporting Sucking Skills In Breastfeeding Infants. Supple Cups are used in many of the top birthing centers.To ensure a correct fit, please review the sizing info in the sizing graphic and measure accordingly. For suction issues or to improve the seal, apply a small amount of lubricant (e.g. KY, lip-balm, nipple cream or butter - such as USP modified lanolin) on nipple and interior of the Supple Cup.For additional information, including frequently asked questions, please visit our website.The Supple Cups name, logo and product design are trademarks of TC Design Works Inc. © 2020 TC Design Works Inc. All Rights Reserved