Contract abdomen and all loose muscle throughout the body.

收紧腹部及全身松弛肌肉。

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You might also contract your pelvic floor muscles just before and during any activity that puts pressure on your abdomen, such as sneezing, coughing, laughing or heavy lifting.

您可以在腹压增大之前和正在增加的时候收缩盆底肌，比如喷嚏、咳嗽、大笑或举重等情况下。

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Your health care provider might massage your lower abdomen to encourage your uterus to contract and expel the placenta.

CNN: Placenta: How it works, what's normal