I was concerned to read your reply to the letter regarding polycystic ovarian disease (Vol 4 no 5). The implication was that all combined oral contraceptives (COCs) are dangerous drugs.
As with any medication, one has to balance wanted with unwanted effects; the reliability of the COC at providing reversible contraception for most women more than outweighs the theoretical risks itemized. It is true to say that some COCs may change the clotting factors in the blood and the ratio of harmful/beneficial subgroups of cholesterol. The tragedies of stroke and heart attack in Pill takers are almost always in smokers. Professor Guillebaud has used the concept of "Safe Pills, Dangerous Women."
Being on COC does not seem to increase the background level of breast cancer risk significantly.
The uncertainty about what in the mechanism of COCs is associated with cervical cancer remains; it may be that the many women who use the COC are also those that have had the many partners at an early age, without the barrier protection that is important in protecting the cervix from male factors.
Cervical smears should pick up early changes, at which stage things are mainly treatable.
As you may surmise, I am a family planning doctor. A E, Surrey.....