She says they threatened to try to take the babies into care if they were born, and that they made the appointment at the hospital.
Channel 4's Dispatches programme has been able independently to confirm this claim. Two doctors refused to give social workers their consent to the abortion because there were no medical grounds for it.
One month after the abortion, Ms McCullagh was sterilised. She was 24 years old. She claims social workers encouraged her to have the operation.
Her allegations have only emerged this year. She says that she decided to make them public because of recent publicity surrounding other complaints made about social workers. The Channel 4 documentary investigated six allegations of serious misconduct indetail, including that of Ms McCullagh, but was made aware of more than 30.
Lancashire social services has been the subject of official scrutiny in the past. In the last four years, the Local Government Ombudsman has handled 75 complaints against the social services department - 50 more than the average for county councils. The county also has the highest number of children in care in Britain.
Ms McCullagh's case began in the early 1980s when she put her two-year-old son into temporary care. She felt she could not cope with him at home Social workers went to court to seek leave for the child's adoption. They argued that Ms McCullagh was a riskto her son because she was an unfit mother. They cited her low IQ, her deprived circumstances, and they said she had aggressive mood-swings.
A court agreed and her child was adopted. She then became pregnant again - this time with a daughter. Two days after the baby was born, she was visited by social workers in hospital and the child was taken into care. There were no allegations of abuse but the social workers continued to argue that she was incapable of being a mother.
Ms McCullagh believes she was targeted because she was poor and uneducated.
She was allowed to see her daughter only occasionally and under supervision after her removal. At 18 months, she was adopted.
After her daughter was removed into care, she became pregnant again. Social workers visited her as soon as they found out. "They told me if I continued with the pregnancy they were going to do the same as what they did with my daughter," she said. "And they kept grilling me all the time. They kept threatening me.
It makes me feel sad and bitter with them. But there's nothing I can do about it. Because I didn't want to go through with it. I didn't want to have a termination. I wanted to keep my baby like a normal mother.''
Later, in the same month, she was sterilised. She claims social workers suggested it and booked the appointment at the hospital.
The director of social services, Pauline Oliver, said: "If I were to find that a member of staff within the department were actively saying to somebody: `I think that you should have an abortion, I think that is a sensible plan for you, or appropriate for you', I would be extremely concerned about it and I would want to know why the social worker was giving that kind of advice and direction and encouragement.''
Ms McCullagh's ordeal took place before the Children Act (1989) was implemented in 1991. This was designed, in the wake of the Cleveland affair, to make social workers more responsive to the needs of parents and children.
But in Lancashire, it is claimed, some social workers have ignored the Act and accompanying guidelines. Another woman alleges that she was put under some pressure to have an abortion in 1992.
She said:"When I told them I was pregnant, he said: `Well, you do know you won't be able to keep it, don't you?'. I did ask him if I didn't have to go through with it and he said: `Well, if you have it we'll have to take it from you anyway'."
The mother tried to commit suicide shortly after having the operation.
The abortion itself was not well performed, and she collapsed as a result of internal bleeding a few days later, and was admitted to hospital.
She had already lost her daughter to care, after her husband - from whom she is now divorced - was accused of sexual abuse. Last week, a court approved the adoption.
The documentary makers attempted to interview all the social workers named during their investigation but were not allowed to speak to them.
Many of the families making the allegations have joined a new action group, based in Blackpool, called Mothers in Action, which is campaigning for a public inquiry into Lancashire social services. Many members of Mothers in Action are planning to take legal action against the authority for compensation.
One family has already been granted legal aid to pursue a case for negligence. At present, however, families cannot sue local authorities for misconduct in child care. Social workers have the same immunity as police from civil prosecution.
The House of Lords is, however, currently hearing a test case which could, if successful, make local authorities financially accountable in child care. The result is expected early next year.
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