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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