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Asian family with two kids

Having a rough idea of when you and your partner would be ready for another baby can be handy. Here are the pros and cons for all sized gaps…

There are no hard and fast rules about what age difference between brothers and sisters works best. Plus, it depends how you think of things and what your family is like. But there are some reasons why a certain age gap might suit you and your family…

Small gap (under two years)


  • You’ll get the most exhausted periods of pregnancy and the early years done all together.  
  • Your children are likely to play together.
  • Your children are more likely to be into similar activities, games and TV shows (which should make your life easier…).
  • When you’re on maternity leave, you’ll get to spend more time with your eldest child too.
  • Having more siblings of a similar age might make kids more creative (Baer et al, 2010).


  • Increased risk of complications in labour, including a rise in pre-term birth (Smith et al, 2003).
  • Can be tiring looking after a toddler when you’re pregnant, especially if your calcium and iron stores are still low from your previous pregnancy (King, 2003).
  • Toddlers might be jealous of or resent a new baby.
  • You’ll have to fork out on more equipment as your eldest child probably isn’t quite ready to pass on their cot, buggy, etc. (AlphaParent, 2015).

Medium gap (two to four years)


  • With this gap, you’ll have the lowest risk of having preterm birth and a low birth weight baby (Zhu, 2005).
  • Your body will have had time to get back to normal after round one (AlphaParent, 2015).
  • You’ll be (mostly) up-to-date with your knowledge about all things baby-related.
  • You can save cash by re-using the baby equipment your first child doesn’t need any more.
  • It’s the most common age gap so your mum friends are likely to have second children at a similar time too.


  • The age gap might be too big for the siblings to play together or have things in common for a while.

Longer gap (over four years)


  • Your older child will most likely be at school so you can get lots of one-on-one time with your newborn.
  • The gap will mean you won’t feel like you’ve been constantly shattered with young babies for years.
  • Your eldest child can help out when the baby arrives.
  • The dynamic can be lovely, with the older child looking after the younger one.
  • Jealousy and resentment might be less of an issue (AlphaParent, 2015).


  • You might have to refresh your baby knowledge quite a bit, with some advice having changed along the way (AlphaParent, 2015).
  • Gaps of over five years are associated with pregnancy and birth problems (not just because you’re likely to be an older mum) (Conde-Agudelo et al, 2006).
  • With bigger gaps, your children may be into different things so not as close until they’re much older.

This page was last reviewed in March 2018.

Further information

Our support line offers practical and emotional support with feeding your baby and general enquiries for parents, members and volunteers: 0300 330 0700.

We also provide Refresher antenatal courses for those parents who have already had at least one baby. They offer a chance to reflect and build on past birth experiences and prepare yourself for looking after your new baby.


AlphaParent. (2015) What no one tells you about child spacing. Available from: [Accessed 1st October 2018]

Baer M, Oldham GR, Hollingshead AB, Jacobsohn GC. (2010) revisiting the birth order-creativity connection: the role of sibling constellation. Creativity Research Journal. 17(1):67-77. Available from:… [Accessed 1st October 2018]

Conde-Agudelo A, Rosas-Bermudez A, Kaffury-Goeta AC. (2006) Birth spacing and risk of adverse perinatal outcomes: a meta-analysis. JAMA. 298(15):1809-1823. Available from: [Accessed 1st October 2018]

King JC. (2003) The risk of maternal nutritional depletion and poor outcomes increases in early or closely spaced pregnancies. J Nutr. 133(5):1732S-1736S. Available from: [Accessed 1st October 2018]

Powell B, Carr Steelman L. (1995) Feeling the pinch: child spacing and constraints on parental economic investments in children. Social Forces. 73(4):1465-1486. Available from: [Accessed 1st October 2018]

Smith GCS, Pell JP, Dobbie R. (2003) Interpregnancy interval and risk of preterm birth and neonatal death: retrospective cohort study. BMJ. 327(7410):313. Available from: [Accessed 1st October 2018]

What to expect. (2016) Spacing your kids: the pros and cons of every age gap. Available from: [Accessed 1st October 2018]

Zhu BP. (2005) Effect of interpregnancy interval on birth outcomes: findings from three recent US studies. Int J Gynaecol Obstet. 89(Suppl 1):S25-33. Available from: [Accessed 1st October 2018]


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