Women who use hormonal contraceptives after giving birth are up to twice as likely to develop postnatal depression, a study suggests.
Researchers say it is ‘important’ health workers highlight the increased risk when discussing the use of contraception with new mums so they can make an informed decision.
The NHS warns women can get pregnant again as little as three weeks after giving birth, even if breastfeeding and their periods have not restarted.
However, many choose to use contraception at this point as waiting less than a year between the end of one pregnancy and the start of another is associated with an increased risk of preterm birth and low birthweight.
For the new study, experts at Copenhagen University Hospital–Rigshospitalet examined data on all 610,038 women who gave birth to their first child in Denmark from 1997 to 2022, with no history of depression in the previous two years.
Of these, four in ten started to use hormonal contraception (HC) within a year of giving birth and the others did not.
Analysis revealed those who used HC were 49 per cent more likely to receive a hospital diagnosis of depression or file a prescription for antidepressants within that year.
This increased the absolute risk from 1.36 per cent to 1.54 per cent, meaning there are expected to be an extra 180 cases of depression for every 100,000 women using HCs.
Women who use hormonal contraceptives after giving birth are up to twice as likely to develop postnatal depression , a study suggests
The proportion of British women taking oral contraceptives has fallen by more than two-thirds, from 420,600 in 2012/13 to 126,400 in 2022/23, according to NHS data
The risk was higher the sooner after birth that they started to take HCs and varied depending on the type they used.
New mums taking combined oral contraceptives, such as some types of ‘the pill’ were 72 per cent more likely to develop depression than those not using HC.
This increased to 97 per cent for those using combined non-oral contraceptives, such as some forms of patches or rings, but was only 40 per cent higher for those using progestogen-only nonoral contraceptives, such as an injection or some types of coil.
The progestogen-only pill was associated with an instantaneously reduced risk in the early study period, but it was increased late post partum.
Writing in the medical journal JAMA Network Open, the researchers said: ‘These findings raise the issue of whether the incidence of depression post partum may be inflated by routine HC initiation, which is important information to convey at postpartum contraceptive counseling.’
UK Government advice on pregnancy planning says: ‘Women should also be advised that an inter-pregnancy interval of less than 12 months between childbirth and conceiving again is associated with an increased risk of preterm birth, low birthweight and small babies for their gestational age.’
Commenting on the findings, Dr John Reynolds-Wright, a lecturer in sexual and reproductive health at the University of Edinburgh, said: ‘Any small increased risk of being prescribed an anti-depressant or being diagnosed with depression, needs to be balanced against the benefits brought by post-partum contraception.
‘This allows women to space births, which improves their and their baby’s health in multiple ways, and gives them reproductive freedom in their lives.
‘We must cautiously interpret the recommendations and findings of this study, particularly given the current global political climate, where reproductive rights are continually under threat.’
