What is birth spacing?
Birth spacing is the period of time between giving birth and getting pregnant again. It's also called pregnancy spacing or interpregnancy interval (also called IPI).
How can having less than 18 months between pregnancies affect your next baby’s health?
Getting pregnant again too soon increases your next baby’s chances of:
- Being premature. Premature babies may need to stay in the hospital longer than babies born later.
- Being born with low birthweight. This is when a baby is born weighing less than 5 pounds, 8 ounces.
- Being small for gestational age (also called SGA). An SGA baby is smaller than normal based on the number of weeks he’s been in the womb.
Babies with these health conditions are more likely to have long-term health problems or die than other babies.
What can you do to help you get the right amount of time between pregnancies?
Here’s what you can do:
- Wait 18 months or more after having a baby before getting pregnant again. Waiting at least 18 months doesn’t mean for sure that your next baby will be born on time. But it can help.
- Use effective birth control (also called contraception) until you’re ready to get pregnant again. Birth control is methods you can use to help keep you from getting pregnant.
- Talk to your health care provider about birth control options.
Talk to your provider about how long to wait between pregnancies if:
- You’re older than 35.
- You’ve had a miscarriage or stillbirth. A miscarriage is when a baby dies in the womb before 20 weeks of pregnancy. A stillbirth is when a baby dies in the womb after 20 weeks of pregnancy.
Why does getting pregnant again too soon increase your chances for premature birth?
Experts don’t know for sure why getting pregnant again too soon increases your chances of premature birth and other health problems for your baby. It may be because your body needs time to:
- Build up its supply of nutrients, like folic acid. Nutrients, like vitamins and minerals, help your body stay healthy. If your body doesn’t have enough nutrients and you get pregnant again too soon, it may cause health problems for you or your baby. For example, during pregnancy and breastfeeding, your baby gets the nutrients she needs from your body. After having a baby, your body may not have enough of certain nutrients, like folic acid. Folic acid is a vitamin that every cell in your body needs for normal growth and development. If you take it before you get pregnant, it can help reduce your baby’s chances of having birth defects of the brain and spine called neural tube defects (also called NTDs). If you get pregnant again too soon and your folic acid levels are low, your next baby is more likely to be born prematurely, with low birthweight or with NTDs.
- Heal from infection and inflammation. Infection during pregnancy can lead to inflammation (redness and swelling) in parts of your body, like the uterus (womb). If you have a condition like endometritis (inflammation of the lining of the uterus) during pregnancy and get pregnant again before your body has fully healed, you may have the condition again in your next pregnancy. Inflammation may play a role in preterm premature rupture of membranes (also called PPROM). PPROM is when the sac (bag of waters) around the baby breaks before 37 weeks pregnancy, causing labor to start. PPROM can cause premature birth.
- Reset the microbiome of the vagina (birth canal). The microbiome is a group of microorganisms. Microorganisms (like bacteria) are living things that are so small you need a microscope to see them. Some experts think the microbiome in a woman’s vagina (called the vaginal microbiome) may play a role in premature birth. For example, having an infection called bacterial vaginosis affects the vaginal microbiome and can increase your chances of having a premature baby. Also, the vaginal microbiome of women who have had a premature baby may be different than that of women who have a baby after 37 weeks of pregnancy. And it may take time—even a year—for the vaginal microbiome to go back to how it was before pregnancy. So getting pregnant again too soon may cause problems in your next pregnancy, like premature birth. The March of Dimes is supporting research to learn more about the vaginal microbiome and premature birth.
More information
Last reviewed: December, 2015