How Close Should You Have Your Babies? The Research Might Surprise You

If you’re wondering whether to space your babies close together or wait longer, you’re not alone. This is a big decision—one that can feel overwhelming when you’re weighing personal, medical, and lifestyle factors. And if you’ve already had children close together, you may be looking for reassurance that it was the right choice for your family.

As a scientist specializing in maternal health—and as a mom of three kids born within three years—I’ve lived both the research and the reality of short birth spacing. My first child was two when I became pregnant again—only to find out I was having twins. So, while I had planned a bit of spacing, life had other plans! If you’re in the thick of raising back-to-back babies or trying to decide whether to go for another, let’s talk about what the science actually says about short interpregnancy intervals (the time between one birth and the next pregnancy).

What the Research Says About Shorter Birth Intervals

There’s been a lot of debate around the “ideal” spacing between pregnancies, with guidelines often recommending waiting at least 18-24 months before conceiving again. Studies suggest that shorter interpregnancy intervals—especially under 12 months—are linked to increased risks, such as:

• Preterm birth: A study published in JAMA Network Open (Schummers et al., 2018) found that women who got pregnant within six months of giving birth had a higher risk of spontaneous preterm birth, particularly for younger mothers.

• Maternal health risks: For women over 35, short interpregnancy intervals were associated with a higher likelihood of maternal complications, including severe morbidity and even mortality. However, these risks were not as pronounced in younger mothers.

• Low birth weight and small-for-gestational-age babies: Some studies suggest that a short interval doesn’t give the body enough time to rebuild key nutrients like folic acid, potentially affecting fetal growth (Hutcheon et al., 2018).

• Labor and delivery complications: Some research points to an increased chance of precipitous labor (labor that progresses too quickly) or uterine rupture in women who attempt vaginal birth after cesarean (VBAC) within a short interval.

However, research (Stanley et al., 2014) suggests that the relationship between short interpregnancy intervals and poor outcomes isn’t as straightforward as once thought. By comparing pregnancies within the same mother, this study found that some risks commonly linked to short intervals may actually be influenced by other factors, such as socioeconomic status, overall maternal health, and access to care.

Context Matters: Why a Shorter Interval Might Be Right for You

Before you panic about the risks, let’s take a deep breath. Research looks at population-level trends, but individual circumstances matter. Not everyone who has babies close together will experience complications.

For example, while studies show an increased risk of preterm birth with short birth spacing, the absolute risk for most women remains low. And in some cases, having children closer together can be beneficial—such as when age-related fertility concerns or medical conditions make waiting less ideal.

Also, birth spacing research often doesn’t capture lifestyle factors. If you have strong social support, access to good nutrition and prenatal care, and feel physically and mentally ready, a shorter interval might work just fine for you. On the other hand, if your body feels depleted, you’re still recovering emotionally from your last birth, or you’re simply exhausted, waiting longer might be better.

My Experience: The Reality of Three Kids in Three Years

When I first became pregnant again, I felt ready. I had waited until my firstborn was two years old, thinking I had planned well—then I found out it was twins! Suddenly, I was facing the reality of three kids in three years.

Is it hard? Absolutely. The sleep deprivation, the logistics, the sheer intensity of these early years—it’s no joke. But would I change it? Not a chance. My kids are growing up close in age, building strong bonds. Every family is different, and for us, we have made this work.

Final Thoughts: Reassurance for Every Mom

If you’re trying to decide when to have your next baby, know this: there is no one-size-fits-all answer. Science provides valuable insights, but the right choice depends on your body, your family, and your circumstances.

And if you’ve already had babies close together and are worried about the risks? Take a deep breath—you’re doing great. Science isn’t here to shame you; it’s here to inform and empower you. Whether your kids are two years apart, three years apart, or surprise twins like mine, what matters most is that they are loved and cared for.

Whatever choice you make, you’ve got this. 💛

References:

• Schummers, L., Hutcheon, J. A., Hernandez-Diaz, S., Williams, P. L., Association of Short Interpregnancy Interval With Pregnancy Outcomes Modified by Maternal Age, JAMA Network Open (2018)

• Hutcheon, J. A., Nelson, H. D., Stidd, R., Moskosky, S., & Ahrens, K. A. (2018). Short interpregnancy intervals and adverse maternal outcomes in high‐resource settings: An updated systematic review. Paediatric and Perinatal Epidemiology.

• Ball, S. J., Pereira, G., Jacoby, P., de Klerk, N., & Stanley, F. J. (2014). Re-evaluation of link between interpregnancy interval and adverse birth outcomes: retrospective cohort study matching two intervals per mother. BMJ, 349, g4333. https://doi.org/10.1136/bmj.g4333