The largest ever study into the psychological impact of early stage pregnancy loss has found that many women suffer post-traumatic stress and anxiety in the weeks after a miscarriage or ectopic pregnancy, while almost one in five experience long-term post-traumatic stress.

The UK and Belgian study involved over 650 women who had experienced an early pregnancy loss. Some 537 had suffered an early miscarriage, which is defined as a pregnancy loss before 12 weeks, while 116 had suffered an ectopic pregnancy, which is when an embryo starts to grow outside of the womb.

The researchers found that one month after the loss, 29% of women were suffering with post-traumatic stress, 24% had moderate to severe anxiety, while 11% had moderate to severe depression.

However, they also found that nine months later, 18% of women still had post-traumatic stress, 17% had moderate to severe anxiety and 6% had moderate to severe depression.

The researchers insisted that women who experience early pregnancy loss need better care in the aftermath.

"Pregnancy loss affects up to one in two women, and for many, it will be the most traumatic event in their life. This research suggests the loss of a longed for child can leave a lasting legacy, and result in a woman still suffering post-traumatic stress nearly a year after her pregnancy loss," explained the study's lead author and consultant gynaecologist, Prof Tom Bourne, of Imperial College London.

He said that the treatment women receive after experiencing an early pregnancy loss "must change to reflect its psychological impact".

"While general support and counselling will help many women, those with significant post-traumatic stress symptoms require specific treatment if they are going to recover fully. This is not widely available, and we need to consider screening women following an early pregnancy loss so we can identify those who most need help," he commented.

As part of the study, the participants completed questionnaires about their emotions and behaviour one month after their loss, and then again three and nine months later. Their responses were compared to 171 women who had experienced healthy pregnancies.

The results revealed much poorer psychological health among the women who had lost a baby when compared to those who had not.

The women found to be suffering with post-traumatic stress said that they regularly re-experienced the feelings associated with the pregnancy loss, and also suffered intrusive or unwanted thoughts about it. Some also reported nightmares and flashbacks.

According to the study's first author, Dr Jessica Farren of Imperial College London, post-traumatic stress can have "a toxic effect on all elements of a person's life, affecting work, home and relationships".

"We have made significant progress in recent years in breaking the silence around mental health issues in pregnancy and postnatally, but early pregnancy losses are still shrouded in secrecy, with very little acknowledgement of how distressing and profound an event they are.

"Many women don't tell colleagues, friends or family they are pregnant before the 12-week scan, leaving them feeling unable to discuss their emotions if they suffer a pregnancy loss. We also know partners can suffer psychological distress following miscarriage or ectopic pregnancy, and are investigating this in ongoing research," she noted.

Details of these findings are published in the journal, the American Journal of Obstetrics and Gynaecology.