Some women who suffer a miscarriage or an ectopic pregnancy may be at risk of post-traumatic stress disorder (PTSD).
Experts from Imperial College London found that almost four in 10 women (38 per cent) in their group met the criteria for probable PTSD three months after suffering the loss of a pregnancy.
Some 113 women took part in the study, published in the journal BMJ Open, filling in questionnaires about their thoughts and feelings after losing a baby.
All of the women had attended the Early Pregnancy Assessment Unit at Queen Charlotte's and Chelsea hospital, West London, for symptoms such as pain or bleeding. Just under half had suffered a previous miscarriage or ectopic pregnancy.
In the study, most women had suffered a miscarriage, while a fifth had suffered an ectopic pregnancy, where the fertilised egg begins to grow outside the womb.
Among the women who suffered a miscarriage, 45 per cent had symptoms of PTSD at the three-month mark, while 18 per cent of the ectopic pregnancy group felt the same.
Those with PTSD reported regularly re-experiencing feelings associated with the pregnancy loss, and suffering intrusive or unwanted thoughts about it.
Some women suffered nightmares or flashbacks, while others went out of their way to avoid family members or friends who were pregnant.
Almost one in three of the women said the PTSD symptoms had impacted on their work, while 40 per cent felt relationships had been affected.
Dr Jessica Farren, lead author of the research, said: "We were surprised at the high number of women who experienced symptoms of PTSD after early pregnancy loss.
"At the moment there is no routine follow-up appointment for women who have suffered a miscarriage or ectopic pregnancy.
"We have checks in place for postnatal depression, but we don't have anything in place for the trauma and depression following pregnancy loss.
"Yet the symptoms that may be triggered can have a profound effect on all aspects of a woman's everyday life, from her work to her relationships with friends and family."