The care of pregnant women in England is being undermined by the lack of involvement of GPs, experts say.
The King's Fund said over the past 30 years the role of the family doctor in helping women before, during and after pregnancy had "all but disappeared".
It suggested they should be paid more as an incentive to take on greater responsibility.
GPs said they would be willing to get more involved, but midwives said doctors needed more training.
The King's Fund compiled the report as part of a larger investigation into GP care generally, which will be published later this year.
It said GPs have traditionally played a key role in helping pregnant women, including - in some cases in the 1970s - delivering babies themselves.
The report is not suggesting a return to this as the professionalisation of midwives and the development of hospital maternity services had done much to improve care.
Instead, the King's Fund said GPs should be doing more to work alongside other services.
It found women often went to their GP to get a pregnancy confirmed, but after that involvement was "very limited".
Researchers argued this was a wasted opportunity. In particular, they said GPs could get involved with pre-conception lifestyle advice and make sure women get the right screening and testing in the early part of pregnancy.
As the pregnancy develops, GPs could then liaise with midwives and obstetric services to share any medical concerns.
And, after the baby is born, doctors could talk to new mothers about common problems such as back pain, mental health issues and contraception.
Dr Laurence Buckman of the British Medical Association said GPs wanted to be more involved in maternity care.
But he added: "There has been a succession of health policy changes in recent years, which have led to the wider primary care team becoming increasingly fragmented.
"Many GPs have watched with growing concern as long-established and valued midwife colleagues have been withdrawn from practice teams and continuity of care for pregnant women has been lost."
A Department of Health spokesman agreed GPs had a "vital" role to play and said this would happen under the shake-up of the health service announced in a White Paper last month.
But Cathy Warwick, head of the Royal College of Midwives, said: "We would argue that if GPs are to have a wider role in maternity care, they must be able to demonstrate an up-to-date knowledge of maternity care and be actively engaged with their local maternity services."