Psychologists say women are left with feelings of guilt at involving their partners in what is essentially a female rite of passage, and this may accelerate the onset of symptoms of depression.
They found that a midwife is of more value to women than a caring partner, acting as a protective "buffer" against women developing depression in the aftermath of pregnancy.
Sandra Wheatley, a research assistant at the academic department of psychiatry at Leicester General Hospital, said the findings "flew in the face of fashion" which now dictates an active role for the male throughout his partner's pregnancy.
Ms Wheatley told the conference that "some women may feel they have accumulated too many 'caring debts' from their partner during their pregnancy, which leave them with feelings of uselessness and increase the rate of development of depressive symptoms".
Post-natal depression is probably caused by a combination of hormonal changes and various psychological and environmental factors.
It can range from a short-lived episode to a severe psychosis in which the woman may need to be hospitalised to prevent her harming herself or the baby.
An estimated two-thirds of women suffer the "blues" which start four or five days after the birth, and last for a week or two. They will feel discouraged, irritable, miserable, and prone to tears.
There is often a sense of anti-climax or an overwhelming feeling of responsibility. In up to 15 per cent of women the depression is more marked and can last for weeks, with symptoms of tiredness, sleeping problems, loss of appetite, and restlessness.
A group of 48 women took part in the Leicester study, completing questionnaires after 34 weeks of pregnancy and again 10-14 days after giving birth. The study concluded that good midwifery care is vital for both the physical and mental health of pregnant women.Reuse content