Pregnancy
and Childbirth Medical Books
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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