From Amnio to Zygote, peep our glossary of all the pregnancy and birth-related terms you never knew existed, 'til now.

Rainbow Baby

/reyn·boh· bey·bee/

Like a rainbow after a rainstorm/thunderstorm, a rainbow baby (or miracle baby) is a baby born after a miscarriage, stillborn or neonatal death. Of course, this brings along with it feelings of happiness but can also trigger sadness, fear and guilt for the parents.



Most pregnant women have symptoms of gastroesophageal reflux disease (GERD), especially heartburn, at some point during their pregnancy, often in the second and third trimesters. Hormones cause the digestive system to slow down and the muscles that push food down the esophagus also move more slowly when you are pregnant. So, as the uterus grows, it pushes on the stomach forcing acid up into the esophagus and causing heartburn. Tums, Zantac, Pepcid AC are all pregnancy safe but check with your doctor if you’re concerned.

Rhesus Disease/Rhesus Factor/RH Factor Test/RH Status

/ree·suh·s· dih·zeez/

Blood types are determined by the types of antigens (proteins on the surface of blood cells that can cause a response from the immune system) on the blood cells. The Rhesus factor (RhD) is a type of protein on the surface of red blood cells. Most people who have the Rh factor are Rh-positive (85% of people). Those who do not have the Rh factor are Rh-negative. If your blood is RhD negative, it isn’t usually a problem, unless your baby happens to be RhD positive. Rhesus disease occurs during pregnancy when the mother and baby’s blood types are incompatible. If a small amount of the baby’s blood enters the mother’s bloodstream during pregnancy or birth, the mother can produce antibodies against the rhesus positive cells that can cross the placenta and destroy the baby’s blood cells, leading to a condition called rhesus disease that can lead to anemia, jaundice and brain damage in the baby. Rhesus disease is uncommon these days (so don’t worry) because it can usually be prevented using injections of Rh immunoglobulin (RhIG) at around 28 weeks to stop your body from making antibodies for the rest of your pregnancy. You’ll receive many blood tests during your prenatal testing during which your doctor will tell you whether your blood is RhD negative or positive.



Rubella, commonly known as German measles, is a contagious disease that affects the skin and lymph nodes and manifests in a fever and rash. Rubella is serious in pregnant women because of its risks including hospitalization and pneumonia and risks to the fetus (your immunity will be tested at your first prenatal appointment). The two-dose series of the measles-mumps-rubella (MMR) vaccine is given to young children, is safe and is 97% effective, but it is not pregnancy safe so it’s good to get a blood test prior to getting pregnant to confirm you’re still immune.