I believe you're remembering "Cord" (also known as "Hide and Seek").
"A desperate doctor and his wife kidnap a pregnant woman, while faking
her death for the outside world. They hold her in their basement,
awaiting the birth of her baby."
Lycos Entertainment: Cord
"Ann (Daryl Hannah), a businessman's wife, is kidnapped... A doctor,
Frank (Vincent Gallo) and his loud wife, Helen (Jennifer Tilly) are
desperate for a child. So they decide to kidnap the pregnant Ann, and
keep her prisoner (in fact in shackles most of the time!). The duo
plans to keep the unborn baby. To avoid arousing suspicion, they stage
Ann's death. But Ann's husband Jack White (Bruce Greenwood) is not
convinced his wife is dead."
The Hindu: Film Review: Hide And Seek
"Jack (Bruce Greenwood) and Ann (Daryl Hannah) are a married couple
whose lives seems nearly perfect, and they couldn't be happier when,
after months of trying, Ann discovers that she's going to have a baby.
Jack is understandably distraught when Ann is kidnapped, and he's
later told that she's been killed. Actually, the truth is considerably
more disturbing -- a psychotic doctor (Vincent Gallo) and his wife
(Jennifer Tilly) want a child but have been unable to conceive, so
they kidnap the pregnant Ann and attempt to falsify her death,
intending to keep her until her child is born, and then raise the baby
as their own. Hide and Seek was also released under the title Cord."
Django Music: Hide and Seek
This movie is available on DVD and VHS. If you're looking to rent it
or purchase it, be careful not to confuse it with a more recent Robert
De Niro film that is also called "Hide and Seek."
Amazon: Hide and Seek DVD
Amazon: Hide and Seek VHS
My Google search strategy:
Google Web Search: "daryl hannah" cord OR "hide and seek"
I hope this is the correct movie. If it is not, or if anything is
unclear or incomplete, please request clarification; I'll be glad to
offer further assistance before you rate my answer.