Here is a list of online books about Gynecology and Obstetrics in various formats available for free :

Antenatal and Postnatal Mental Health

National Collaborating Centre for Mental Health, 2007, 369 pages, 3MB, PDF

Antenatal Care: Routine care for the healthy pregnant woman

National Collaborating Centre for Women’s and Children’s Health, 2008

Antibiotics for Early-Onset Neonatal Infection

RCOG Press, 2012, 325 pp, 3.1MB, PDF

Diabetes in Pregnancy

National Collaborating Centre for Women’s and Children’s Health, 2008, PDF

Ectopic Pregnancy and Miscarriage

RCOG Press, 2012, 287 pp, 3.2MB, PDF

Emergency Childbirth: A Reference Guide for Students

by United States Office of Civil Defense and United States Public Health Service, 1970

Induction of Labour: Clinical Guideline

National Collaborating Centre for Women’s and Children’s Health, 2008, 124 pages, 1.2MB, PDF

Intrapartum Care

National Collaborating Centre for Women’s and Children’s Health, 2007, 3.1MB, PDF

Iowa Neonatology Handbook

by Edward F. Bell, Jeffrey L. Segar, 2006

Managing Complications in Pregnancy and Childbirth

World Health Organization, 2007, 390 pp, 5.5MB, PDF

Maternal-Fetal Surgical Procedures

by William F Walsh, at al. 2011, 164 pages, 1.7MB, PDF

Menopause A to Z

by Warwick Carter, 2011, 53 pp, 1.3MB, PDF

Multiple Pregnancy

National Collaborating Centre for Women’s and Children’s Health, 2011, 235 pp, 3.5MB, PDF

Neonatal Care

edited by Deborah Raines, Zoe Iliodromiti, 2012, 96 pp, 1.5MB, PDF

Nutrition During Lactation

Committee on Nutritional Status During Pregnancy and Lactation, Institute of Medicine, 1991

Nutrition During Pregnancy

Committee on Nutritional Status During Pregnancy and Lactation, Institute of Medicine, 1990

Obstetrics in Remote Settings

by Anne-Sophie Coutin, et al. 2007, 222 pages, 3.5MB, PDF

Perinatal Mortality

edited by Oliver C. Ezechi, Karen Odberg-Petterson, 2012, 148 pp, 18MB, PDF

Postnatal Care: Routine Postnatal Care of Women and Their Babies

by Demott K, et al., 2006, 393 pp, 1MB, PDF

Pregnancy A to Z

by Warwick Carter, 2011, 42 pp, 1.9MB, PDF

Preterm Birth

edited by Offer Erez, 2013, 189 pp, 6.8MB, PDF

Preterm Birth: Mother and Child

edited by John C. Morrison, 2012, 368 pp, 6.3MB, PDF

Progestogens for Prevention of Preterm Birth

by Frances E Likis, et al. 2012, 363 pp, 2.9MB, PDF

Safe Abortion

World Health Organization, 2013, 134 pp, 1.6MB, PDF

Vascular Biology of the Placenta

by Yuping Wang, Shuang Zhao, 2010, 100 pp, online html