In a matter of weeks of continued wear, the nipple will stay erect. Ideally use before becoming pregnant. However, you can also use in the first six months of pregnancy to achieve long-lasting correction. Any nipple inversion which is not congenital but has occurred recently should be immediately checked by a doctor before the Niplette is used. Use is not recommended in the last trimester of pregnancy.
The Niplette: an instrument for the non-surgical correction of inverted nipples DD McGeorge FRCS (Plast). British Journal of Plastic Surgery, December 1993
Use with inverted or flat nipples
The Niplette is suitable for correcting inverted nipples which have developed as a result of hereditary factors or during puberty