Foetus Cervix Vagina Fig. 8 A human embryo 5–6 weeks after fertilisation. 13.10 Birth
The birth of a baby begins when the muscles of the uterus (womb) start to contract. This is called labour. Contractions cause the cervix (the neck of the womb) to open up. The bag of amniotic fluid bursts, and further contractions push the baby out, usually head first. The umbilical cord is clamped and then cut. Shortly afterwards, the placenta (afterbirth) is also pushed out.
13.11 Family planning
If parents want to control the number of children they have, they must control the number of times fertilisation takes place. There are a number of family planning methods, but none is 100% reliable. Natural methods: Natural methods of contraception aim to detect the day on which
ovulation takes place and then to avoid intercourse during the fertile period. Artificial methods: Artificial methods involve preventing the sperm and egg from meeting
by using a barrier (e.g. a condom). Such methods prevent fertilisation from taking place. The contraceptive pill uses chemicals (hormones) to prevent ovulation.
Medical issues – Fertility It is not always easy for doctors to decide the best way to help a couple who are infertile. In considering the best treatment for a particular couple, doctors must consider a number of medical issues. Medical issues include possible side effects of medicines or risks associated with surgery. Medical issues will be different for different couples depending on their age and medical history.
Science in Society What medical treatments are available to assist couples experiencing difficulty having children naturally? What medical issues arise in considering these treatments?
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Medical Issues Issues which arise during medical treatment.
Fig. 9 The baby develops inside the uterus.
Foetus The developing baby after eight weeks in the uterus. It is now recognisably human.
