When it comes time to grow your family, there’s a chance there’s not going to be a whole lot of actual planning happening. According to a study published in 2016, almost half (45 percent) of pregnancies in the United States are unintended. (Of course, a high percentage of couples do also plan meticulously for children due to infertility struggles.)
Unplanned pregnancies are common enough nowadays that even celebrities feel comfortable sharing the details of their happy accidents. In 2009, Kourtney Kardashian told People she considered getting an abortion when she accidentally became pregnant with her son Mason. Meanwhile, Tori Spelling admitted in a 2012 interview that her fourth child Finn was conceived when her daughter Hattie was just a month old.
"The doctor said, 'Wait six weeks [to have sex],' and Dean was like, 'They tell everyone that,’” she told the magazine. “We didn't wait that long with Stella or Liam. I was like, 'Well, I don't want him to think that the sex is going downhill,' so now we're on baby No. 4."
Despite some of the perceived perks of having kids back to back like that—for example, having two little ones close in age means they’ll play together—research recently published in JAMA Internal Medicine suggests that taking measures to plan when you have children could potentially reduce health risks for both you and your mini-me.
Researchers from the University of British Columbia and the Harvard T.H. Chan School of Public Health were interested in investigating whether the amount of time between when you give birth and subsequently get pregnant again increased the risk of something bad happening to you or your baby. (Let’s not forget that the rate of women in the United States dying due to pregnancy- or childbirth-related causes is the highest among all developed nations, and it’s still rising.)
For their analysis, the study’s authors looked at the records of 148,544 pregnancies in Canada. Among women older than 35 who conceived six months after giving birth, researchers found an increased risk of death and/or severe negative impacts on a woman’s health. Getting pregnant half a year after having a child also upped the likelihood of adverse outcomes for the baby, including being delivered too early. This was the case for women of all ages, though the risks were slightly higher for moms between the ages of 20 and 34.
According to the study’s findings, the ideal length of time to wait to have another kid appears to be 12 to 18 months.
Dr. Sonia Hernandez-Diaz is a professor of epidemiology at the Harvard T.H. Chan School of Public Health and one of the authors on the study. In a statement, she offered her take on the importance of better planning: “Short pregnancy spacing might reflect unplanned pregnancies, particularly among young women. Whether the elevated risks are due to our bodies not having time to recover if we conceive soon after delivering or to factors associated with unplanned pregnancies, like inadequate prenatal care, the recommendation might be the same: improve access to postpartum contraception, or abstain from unprotected sexual intercourse with a male partner following a birth.”
So if it’s always been your plan to do the “two under two” thing, make sure to consider all aspects before committing yourself to what’s sure to be utter chaos anyway.