Raynaud's is a fairly rare disorder of the blood vessels supplying the skin. During a Raynaud's attack, the blood vessels narrow, limiting blood circulation to affected areas. It makes parts of your body (usually fingers, toes, nose and ears) feel numb and cool in cold temperatures or under stress.
PPROM is associated with 30-40% of preterm deliveries and is the leading identifiable cause of preterm delivery. PPROM complicates 3% of all pregnancies and occurs in approximately 150,000 pregnancies yearly in the United States.
That goes for swimming, too, even though you may not feel dehydrated. An increase in core body temperatures in early pregnancy can cause fetal defects, and dehydration in late pregnancy is associated with premature labor. Always include a warm-up and cool-down when putting muscles to work.