Handcuffs during pregnancy, separation from newborn babies and insufficient care for elderly inmates are among the abuses suffered by women incarcerated in Japan, Human Rights Watch (HRW) has said Tuesday.

Female inmates are sometimes shackled during labor and immediately after birth, the international NGO alleged in a new report, based on interviews with nearly 60 formerly jailed women.

The Justice Ministry denied some of the claims, saying that restraints are "not used when imprisoned women are breastfeeding, holding, bathing, or changing the baby's diapers," according to the report.