A woman cannot become pregnant because her ovaries do not release eggs. Doctors treat her using in vitro fertilisation (IVF).
The woman is first given injections of FSH and LH.
Explain why.
The Table shows the success rate of IVF for women of different ages.
Table
| Age of woman in years | Percentage of IVF cycles that result in a live birth |
|---|---|
| under 35 | 32 |
| 35 to 37 | 25 |
| 38 to 39 | 19 |
| 40 to 42 | 12 |
| over 42 | 4 |
A clinic carries out 250 IVF cycles for women aged 40 to 42.
Calculate the number of these cycles that would be expected to result in a live birth.
Doctors sometimes place more than one embryo in the uterus.
Give one advantage and one disadvantage of doing this.
After the embryos are placed in her uterus, the woman is given progesterone.
Suggest why.
84 exam-style questions on OCR GCSE Biology 3.2 Coordination and control – the endocrine system, covering 3.2.1 Principles of hormonal coordination and control, 3.2.2 Roles of thyroxine and adrenaline, 3.2.3 Hormones in human reproduction, 3.2.4 Interactions of reproductive hormones, 3.2.5 Hormones in contraception, 3.2.6 Hormones in reproductive technologies, 3.2.7 Plant hormones in growth and coordination, 3.2.8 Effects of plant hormones, and 3.2.9 Uses of plant hormones. Each one has a worked solution and a mark scheme showing where the marks go.