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Reduction in protein S activity during normal pregnancy

Gotaro Kurasawa1, Kazuhiko Kotani, Yuji Ito

  • 1Department of Obstetrics, Nishiagatsuma Welfare Hospital, Naganohara, Gunma, Japan. gotaro@bird.zero.ad.jp

The Australian & New Zealand Journal of Obstetrics & Gynaecology
|June 7, 2007
PubMed

We investigated the serial changes in blood protein S (PS) and related proteins in 11 normal pregnant women. The PS activity decreased significantly in the third trimester and reached minimum levels (23.3%) one hour after delivery. Although the PS activity was reduced markedly below the normal limits, all the women delivered safely. The mechanisms that cause the reduction in PS activity and the clinically dangerous conditions involving PS activity during pregnancy warrant further investigation.

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