Length of the third stage of labor at term pregnancies is shorter if placenta is located at fundus: prospective study.
OBJECTIVE
To investigate how the location of the placenta at term pregnancies affects the duration of the third stage of labor and to discuss the possible mechanisms affecting the duration of the third stage. We believe that this is the first prospective study comparing the duration of the third stage of labor according to placental location.


METHODS
The placental implantation was determined as anterior (n = 78), posterior (n = 59), or fundal (n = 64) by ultrasound, in 201 women with singleton pregnancies. After delivery of the newborn, oxytocin infusion was routinely given. Duration of the third stage of labor was compared by anova. P < 0.05 was determined as significant.


RESULTS
The duration of the third stage of labor was 10.36 +/- 5.94 min, 10.44 +/- 5.35 min, and 8.12 +/- 4.25 min with placentas located anteriorly, posteriorly, and fundal, respectively. The length of the third stage was significantly shorter in the fundal placenta group.


CONCLUSIONS
In this study, the length of the third stage of labor was approximately 2 min shorter with placentas located at the fundus compared to the other two groups. The mechanism responsible for shorter duration may be the bipolar separation of fundal placentas in contrast to usual unipolar down-up separation of anterior or posterior placentas. Another contributing factor may be the use of oxytocin infusion for the management of the third stage, however this should be investigated by further studies by using real time ultrasonography.
Altay
M Metin
MM
Turkish Ministry of Health Ankara Etlik Maternity and Women's Health Academic and Research Hospital, Ankara, Turkey. altay_metin@yahoo.com
Ilhan
Ali Kemal
AK
Haberal
Ali
A
D000328:Adult; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007749:Labor Stage, Third / Q000502:physiology*; D010121:Oxytocin / Q000494:pharmacology; D010920:Placenta / Q000000981:diagnostic imaging / Q000502:physiology*; D011247:Pregnancy; D011446:Prospective Studies; D014463:Ultrasonography
D010121:Oxytocin