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Pregnancy
and Childbirth
:
Great advances were made in birth control with the improvement of
intrauterine devices in the 1950s and the development of the birth
control pill in 1960 by the American biologist Gregory Pincus. By
the 1990s long-lasting hormonal implants and contraceptive injections
such as Depo-Provera were developed. These options gave women more
control in deciding whether to become pregnant. Voluntary sterilization,
involving vasectomies in men and tubal sterilization in women, emerged
as a popular way of permanent birth control. Unwanted pregnancies,
however, remained a serious problem in the late 1990s. Researchers
still sought more convenient and safer methods of birth control,
including a male birth control pill.
By
1975 physicians were able to diagnose some congenital or inherited
diseases before childbirth. Doctors take samples of placental cells
or of the amniotic fluid around the fetus to determine whether hereditary
blood diseases, Down syndrome, defects of the spine, or other congenital
diseases are present. Even the sex of a fetus may be known in advance.
In
addition to advances in early diagnosis, progress occurred in identifying
the causes of some birth defects. Excess alcohol consumption during
pregnancy was linked to fetal alcohol syndrome, and inadequate intake
of the vitamin folic acid was linked to spina bifida and other neural
tube defects.
Advances
in treating infertility, which prevents couples from having children,
began with the world's first so-called test-tube baby born in the
1980s through in vitro fertilization. Other forms of assisted reproduction
soon became available. Researchers in 1997 cloned a lamb from cells
taken from an adult ewe. It led to speculation that human cloning
could become another option in human reproduction.
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