**Author details**

Mariko Ueno1 , Mitsue Muraoka2 and Koichiro Takagi3 \*

1 Department of Obstetrics and Gynecology, Tokyo Women's Medical University Medical Center East, Tokyo, Japan

2 Department of Obstetrics and Gynecology, Shiseikai Daini Hospital, Tokyo, Japan

3 Saigusa Maternity Clinic, Tokyo, Japan

\*Address all correspondence to: kotak0821@gmail.com

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
