A large proportion of stillbirths happen in otherwise healthy babies, and the reason often can't be explained. But there are some causes we do know about.

Complications with the placenta

Many stillbirths are linked to complications with the placenta. The placenta is the organ that links the baby's blood supply to the mother's and nourishes the baby in the womb.

If there have been problems with the placenta, stillborn babies are usually born perfectly formed, although often small.

With more research, it's hoped that placental causes may be better understood, leading to improved detection and better care for these babies.

Other causes of stillbirth

Other conditions that can cause or may be associated with stillbirth include:


Usually this will be a bacterial infection that travels from the vagina into the womb (uterus). These bacteria include group B streptococcus, E. coli, klebsiella, enterococcus, Haemophilus influenza, chlamydia, and mycoplasma or ureaplasma.

Some bacterial infections, such as chlamydia and mycoplasma or ureaplasma, which are sexually transmitted infections, can be prevented by using condoms during sex.

Other infections that can cause stillbirths include:  

Increased risk

There are also a number of things that may increase your risk of having a stillborn baby, including:

Your baby's growth

Your midwife will check the growth and wellbeing of your baby at each antenatal appointment and plot the baby's growth on a chart.

Every baby is different and should grow to the size that's normal for them. Some babies are naturally small, but all babies should continue to grow steadily throughout pregnancy.

If a baby is smaller than expected or their growth pattern tails off as the pregnancy continues, it may be because the placenta isn't working properly. This increases the risk of stillbirth.

Problems with a baby's growth should be picked up during antenatal appointments.

Your baby's movements

It's important to be aware of your baby's movements and know what's normal for your baby.

Tell your midwife immediately if you notice the baby's movements slowing down or stopping. Don't wait until the next day.

See preventing stillbirth for more information.

Page last reviewed: 1 August 2019
Next review due: 1 August 2019