Please choose the correct ending to complete the given sentence: Health: [header] How to tell if you are in labor with a second pregnancy [title] Check to see if your water has broken. [step] Usually, most women recognize that labor is starting when they feel that their " water broke ". This is when the amniotic membranes rupture spontaneously.

Ending1: This event triggers the start of uterine contractions. [title] Keep track of any contractions you feel. Ending2: This process results in an abnormally large membrane separating the uterus from the larger embryo. [title] Take a prescription for amniotic fluid. Ending3: Amniotic fluid leaks into the placenta as the baby grows. Amniotic fluid leaks onto the placenta. Ending4: [title] Recognize during pregnancy that blood restores its ability to store more amniotic fluid. [step] The amount of amniotic fluid required varies according to activity levels.

Answer format: ending1/ending2/ending3/ending4