Nosebleeds during pregnancy are caused by an increase in blood volume and hormones, according to KidsHealth. Rising levels of the pregnancy hormones progesterone and estrogen cause an increase in blood flow to mucous membranes, including the nose, as stated on What to Expect, and these same hormones make the blood vessels open wider, according to Baby Center, while the increased blood volume puts extra pressure on the small blood vessels.
The same conditions that cause nosebleeds are also responsible for congestion, snoring and softening of the gums that leads to bleeding when brushing teeth or flossing, states the Mayo Clinic. Occasional nosebleeds during pregnancy are harmless, notes Baby Center.
To stop a nosebleed, Baby Center advises sitting down with the head higher than the heart and applying pressure to the bleeding nostril by pinching it between the thumb and forefinger. Tilting the head back is not recommended as doing so may cause blood to be swallowed, and that causes nausea. Applying ice also helps stop nosebleeds by restricting the blood vessels. Baby Center advises blowing the nose gently, staying hydrated by drinking plenty of fluids, keeping the mouth open during a sneeze, avoiding dry air, and lubricating the nose with petroleum jelly, nasal drops or saline spray to avoid getting nosebleeds.