In fact, a short amount of time between pregnancies is associated with more complications and may place your subsequent pregnancy at risk, says ob-gyn Marielena Guerra, M.D., of Elite OB/GYN in Florida. One meta-analysis in 2006 found that an interpregnancy interval of less than 18 months was associated with a slightly increased risk of low birth weight, preterm birth, and small size for gestational age. Additionally, babies conceived less than six months after their siblings had a 40 percent increased risk of being born prematurely and a 61 percent increased risk of low birth weight, compared to women who conceived at least 18 months later.
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What's more, when pregnancies occur close together, there is an increased risk of anemia in the second pregnancy, which could spell trouble for both mom and baby, says Guerra. While it’s not clear exactly what is mediating these links, it could be that mom hasn’t had enough time to build back up her stores of crucial nutrients. The World Health Organization currently recommends spacing pregnancies between two and five years apart.
Finally, a quick second pregnancy can make breastfeeding more complicated than it already is, says Guerra. Breastfeeding triggers the release of oxytocin, the hormone responsible for contractions. So if you breastfeed while pregnant, you could experience more—and stronger—Braxton Hicks contractions, she says. Meanwhile, pregnancy may stunt your milk production.
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Of course, you can’t always space out your pregnancies exactly as you wish, so Guerra recommends talking to your doctor before you’re ready to conceive again or if you unexpectedly get pregnant shortly after your first birth. They’ll be able to give you personalized advice for having a healthy and safe pregnancy—though they may not be able to help with the two-running-toddlers-under-one-roof part.
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