"Miscarriage can lead to 'long-term post-traumatic stress'," reports BBC News.
Early pregnancy loss affects many women. This can happen through miscarriage, or the less common condition of ectopic pregnancy, when a pregnancy develops outside the womb (usually in the fallopian tube) where it cannot grow.
Losing a baby in the early stages of pregnancy has been linked to anxiety and depression, but there has been little study of post-traumatic stress in women who have lost pregnancies.
This London-based study used questionnaires to identify symptoms of anxiety, depression and post-traumatic stress in women who had had an early pregnancy loss. Questionnaires were sent to women 1 month, 3 months and 9 months after the pregnancy loss.
The results showed that, out of the women answering the questionnaire at 1 month:
At 9 months after a pregnancy loss, 18% had symptoms of post-traumatic stress.
The authors say the results suggest healthcare providers should be more aware that pregnancy loss can have an impact on women's mental health, and should ensure women can get suitable support and treatment where needed.
Find out more about how to manage the emotional impact of pregnancy loss, and where to get support for miscarriage.
The study was carried out by researchers at Imperial College London, UK, and KU Leuven in Belgium. It was funded by the Imperial Health Charity, National Institute for Health Research and Tommy’s charity. It was published in the peer-reviewed American Journal of Obstetrics and Gynecology.
BBC News' report of the study included a case study of a woman who experienced PTSD following a miscarriage, but did not give much detail about the study. The Independent and the Mail Online both gave a good overview of the study and explained some of its limitations.
This was a cohort study comparing rates of mental health symptoms in women with early pregnancy loss and those with ongoing pregnancies.
Cohort studies are good ways to investigate links between risk factors (in this case early pregnancy loss) and outcomes such as depression, anxiety and post-traumatic stress.
However, without more in-depth assessment of each woman, the study cannot prove that the pregnancy loss was the sole factor causing the outcome, or the reasons why it happened.
In this case, the researchers mainly wanted to find out how common symptoms like post-traumatic stress are after pregnancy loss.
Researchers recruited 737 women who had experienced early pregnancy loss, either by miscarriage or a pregnancy that could not develop. Early miscarriage is usually defined as pregnancy loss before 12 weeks, but the researchers did not make clear their definition of 'early pregnancy loss' in this study.
Researchers also recruited 171 women with ongoing pregnancies to act as a control group, at the time of their 11 to 14 week scan.
Women who agreed to participate were sent questionnaires to assess their mental health, 1 month, 3 months and 9 months after the pregnancy loss (or after recruitment, for the control group).
One questionnaire assessed anxiety and depression symptoms using the Hospital Anxiety and Depression Scale, HADS. The other used the Post-traumatic stress Diagnostic Scale (PDS) to assess symptoms of post-traumatic stress, including re-experiencing the symptoms of the pregnancy loss. Re-experiencing involves involuntarily reliving the event, through flashbacks, nightmares, and distressing images or sensations.
The control group filled in only the HADS.
Women were also asked about their previous pregnancies, including other pregnancy losses, whether they were pregnant again at the time of filling in the questionnaire, and whether they had experienced a further pregnancy loss.
The researchers compared the rate of anxiety and depression among women with pregnancy loss with that of women whose pregnancies were ongoing.
They adjusted the figures to take account of the mother's age, whether the pregnancy was conceived by IVF, whether they had other children and whether they'd had previous pregnancy loss. They looked at how symptoms changed over time.
The study involved 737 women with pregnancy loss. This included 537 women with miscarriage and 116 ectopic pregnancies. It also included some women diagnosed with pregnancy of unknown location (PUL), when there is a positive pregnancy test but no signs of a pregnancy in the uterus.
The researchers considered the group as a whole, and did not compare experiences between women with miscarriage and ectopic pregnancy, because of the smaller number with ectopic pregnancies.
Of the 737 women with pregnancy loss, 67% answered the HADS at 1 month, 58% answered it at 3 months and 46% at 9 months.
A similar proportion completed the PDS.
The control group included 171 women with ongoing pregnancies, 51% of whom completed the HADS questionnaire.
Of women with pregnancy loss (responding to the questionnaires) symptoms of post-traumatic stress were shown by:
Symptoms of moderate to severe anxiety were shown by:
Symptoms of moderate to severe depression were shown by:
For comparison, 13% of women with ongoing pregnancies had moderate to severe anxiety when questioned at about 11 to 14 weeks, and 2% had symptoms of moderate to severe depression.
Women who had a pregnancy loss were:
The researchers said: "The fact that such a high proportion of women experience symptoms suggestive of PTSD, and that these symptoms persist over time, is important."
They added: "Women often suffer long waiting times for review or treatment, as well as insensitive communication or management. We should strive to provide access to specialist early pregnancy assessment care where expert advice is available, as well as an awareness of the potential psychological response and need for appropriate treatment."
Women experience pregnancy loss in different ways. For many women, it is a distressing and painful experience. This study shows that it can have a big impact on women's mental health, both immediately after the event and for months to come.
There may be a tendency not to talk about early pregnancy loss and the extent of its effect, especially in the first 12 weeks when people may not have told family and friends about the pregnancy. But this silence can make it difficult for women who are struggling with the aftermath of miscarriage to get the help and support they need.
The National Institute of Health and Care Excellence (NICE) recommends that women who have experienced pregnancy loss should be given information about how to access support and counselling services, and that women should be offered a follow-up appointment if they wish.
The study, while useful, has 1 main limitation – the high drop-out rate. Of 1,098 women with pregnancy loss asked to participate, only 737 (67%) agreed, and only 530 completed at least 1 of the 3 questionnaires.
It's possible that women who agreed to complete the questionnaire might be more or less likely to experience problems than those who dropped out, which would affect how representative the results are of women with pregnancy loss.
It's also possible that completing the questionnaires might affect women's emotional response to the pregnancy loss, by encouraging them to think about their experience.
Although the study talks about women experiencing symptoms of post-traumatic stress, this is not the same as being diagnosed with post-traumatic stress disorder, which cannot be diagnosed from a questionnaire. Some of the women might have had PTSD, but we cannot tell from this study.
The study is unable to tell us how many women may continue to experience mental health effects from pregnancy loss in the longer term, beyond 9 months after the pregnancy loss. Nor can it tell us of the wider impact pregnancy loss may have on other areas of the woman's life, for example family, relationships or working life.
It may also cause considerable anxiety in future pregnancies. The overall impact may also be greater with the number of miscarriages a woman has had.
We cannot be sure exactly what proportion of women experience mental health problems after pregnancy loss. But given how many women experience pregnancy loss, the study suggests that many women may experience significant mental or emotional ill-health in the months following such an event. It is important they are able to get the care they need.