Mums who have babies too close together are putting themselves and their child at risk, according to a new report.
But what's too close?
According to experts from the American Centers for Disease Control and Prevention (CDC), mothers should leave 18 months after their baby is born before getting pregnant again.
Any shorter and mums risk 'serious medical complications for both her and her next newborn'.
In the States, a third of women become pregnant again less than 18 months after their baby's birth – and that causes problems, says a report by the CDC.
It added that short interval between pregnancies may also 'affect the risk of pregnancy complications, such as preterm birth, low birth weight, and small gestational age'.
Douglas Richards, a doctor specialising in maternal and foetal medicine, added that women who have had a C-section particularly need to give their bodies time to heal between pregnancies.
He said: "Another group of women that we really strongly emphasise waiting is women who've had a Caesarean and hope to have a vaginal birth with the next pregnancy.
Using the time to heal physically, and emotionally, is also very important for baby, as it gives them some much-needed one-on-one time with mum.
Dr Richards said: "If she's having a difficult time coping with new babies, it takes some time for her to get used to that and get the children to an age where she feels psychologically and emotionally, and as far as the family dynamic is concerned, she is ready to bring another child into the family."
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