Chris Huhne demanded that ex-wife Vicky Pryce have a second abortion, which she refused, a court has heard.
Pryce told Southwark Crown Court the former energy secretary forced her to terminate her pregnancy in 1990 because it was "bad for his career".
She also told the court he made the same demands two years later when she accidentally fell pregnant, but said "I couldn't bring myself to do it."
Pryce denies perverting the course of justice and claims Huhne bullied her into taking his speeding points in 2003.
Pryce, who already had two children from a previous marriage and two with Huhne, said of the abortion: "It was all booked and I was meant to go that morning. I woke up and knew how I had felt about the previous one and knew I couldn't do it. I just couldn't bring myself to do it and I had learned from the previous one."
Asked how Huhne pressured her to have the first abortion, Pryce said: "He didn't say, 'I will divorce you if you carry on', but it was obvious that the environment in the house would be pretty bad if I carried on and that of course would simply have added to the strain."
She told the court: "Mr Huhne was somebody who wanted to achieve his aims and nothing could come in his way of doing so. His aims, of course, were mainly political or financial, depending on the period in his life, so that was absolutely at the top of his agenda. So whenever it came to anything that might affect either his political career or ... financial stuff, he would certainly win."
The economist, who is said to have leaked the story about the points to the press in a bid to "nail" her husband after he left her for PR adviser Carina Trimingham, said she "wanted to turn the clock back" when the story hit the headlines.
Pryce, 60, revealed the scandal to Sunday Times political editor Isabel Oakeshott in March 2011 and the pair agreed a way of producing the story aimed to protect Pryce from prosecution.
Pryce denied perverting the course of justice, which Huhne earlier pleaded guilty to. The case was adjourned to Monday morning.