Excretion of excess body fluids

During the pregnancy, the woman's body contains more body fluids than in the non-pregnant state. Some of this additional water is held in her tissues, some in her increased volume of blood, and some in the uterus. This excess water is rapidly eliminated after the birth. The amniotic fluid drains away through the vagina. From the second day after the delivery, the urine volume will increase up to three litres per day for a few days, but within one week it returns to the normal pattern of urination. The bladder increases its capacity during the period in which excess body fluids are being eliminated, filling with between 1,000 to 1,500 ml of urine without discomfort.If urine is retained for long periods in the bladder, because the urethra is obstructed by swollen or bruised tissues after the birth, it increases the risk of urinary tract infections developing.