The clinical study of linea nigra in pregnancy

Kim, Beom Joon; Ahn, Ji Young; Park, Kui Young; Lee, Eun Sil; Huh, Chang Hun; Won, Chong Hyun; Kwon, Oh Sang; Kim, Myeung Nam

Abstract

OBJECTIVE
The purpose of this study was to evaluate the relationship between linea nigra and the sex of fetus, neonatal weight, parity, route of delivery, and neonatal disease.
METHODS
41 pregnant women (20 primiparas and 21 multiparas) between 25 and 35 years were included between January and December 2004. We examined the time of appearance and disappearance of linea nigra and morphological differences between linea nigras above the navel and below the navel. Also, we observed the difference of linea nigra according to fetal sex, neonatal weight, parity, interval of childbirth, route of delivery, and the use of whitening cream by answering.
RESULTS
The linea nigra was observed in 39 persons (95.1%), and the change of width preceded the change of color among 83.3%. During the third gestational period, the linea nigra became darker the most obvious among 62.5%. Most disappeared rapidly within 3 to 6 months after childbirth among 46.1% of primiparas, meanwhile within 3 months among 60% of multiparas. The linea nigra below the navel became more darker (90%) and wider (79%) than above. However, the linea nigra above the navel disappeared faster. In cases of male babies (63.7%), linea nigra was more darker and wider. The illness of newborns, use of whitening cream, route of delivery and the interval between the first and subsequent childbirth were not found to affect the change of linea nigra.
CONCLUSIONS
We thought that this study could be useful to understand the morphogenesis of linear nigra in Korean pregnant women.