Introduction
Delay in placental delivery may cause heavy bleeding in late pregnancy.
Therefore, it is recommended that obstetric providers use uterotonic
agents immediately after delivering the foetus and deliver the placenta
by controlled cord traction1). Retained products of
conception (RPOC), in which placental tissue remains in the uterus after
delivery, occur in about 1% of pregnant women and causes severe
postpartum haemorrhage2,3). The National Institute for
Health and Clinical Excellence (NICE) and the World Health Organization
(WHO) recommend that obstetric providers perform manual removal of the
placenta (MROP) if it is not expelled within 30 minutes to 1 hour after
the baby is delivered4). However, MROP may increase
the risk of hysterectomy and death due to heavy bleeding. Additionally,
the placenta often remains partly after MROP5). If
conservative management is chosen immediately after deliver, or RPOC
occurs after MROP, there is a risk of subsequent massive haemorrhage or
infection6-9). Therefore, some studies suggest that
RPOC should be removed by transcervical resection (TCR) to avoid
bleeding and infection during conservative
management10,11). However, surgical RPOC removal also
carries a high risk of massive bleeding12).
Recently, several Japanese facilities have reported that RPOC
spontaneously disappeared without surgical
management13,14). However, evidence for the
conservative management of RPOC, especially after term delivery, is
lacking, and there are no criteria to determine which cases can achieve
spontaneous resolution15,16). It is also unclear when
major bleeding or infection occurs and how long it will take for RPOC to
be absorbed spontaneously.
Our hospital is the only university hospital in the South Osaka
district, and most patients with RPOC in this area are referred to our
hospital. We have treated many cases with RPOC conservatively until they
spontaneously disappear. This study aimed to analyse the clinical course
of RPOC after 34 weeks of gestation and to elucidate its natural
history. The results of this study show that conservative management
should be incorporated into the standard treatment for RPOC.