Pill risks
Q My 18-year-old daughter wants to go on the pill but has read that it can cause cervical cancer. I had never heard of this before. Is it a real risk?
A We have all heard of worries about an increased risk of thrombosis or breast cancer on the pill. And the concern about cervical cancer is similar, though less well publicised for some reason. However, the health risks of pregnancy far outweigh any risks from the pill and there are some positive health gains that your daughter will want to balance against the potential risks.
If 100,000 women use the pill for a year, there will be, on average, eight extra cases of invasive cancer of the cervix (and 41 extra cases of pre-cancer). But there will be about nine fewer cases of ovarian and endometrial (womb) cancer because the pill protects against these.
We know that the main preventable risk of cervical cancer is genital warts (HPV). Your daughter can protect herself against HPV by using condoms and limiting her number of sexual partners. Regular cervical smears can pick up signs of HPV and specific screening tests for HPV will probably be introduced in the next decade.
Blood worries
Q I am rhesus negative and have just found out that I am pregnant. I was told at the antenatal clinic that I needed to have an injection of anti-D. I am concerned because I know it comes from blood and worry that there might be risks to me or my baby. Should I have it?
A Rhesus negative women who get pregnant from rhesus positive dads can have babies who are rhesus positive. If this happens, the mother can make antibodies against the rhesus positive red blood cells. These antibodies can cross the placenta and damage subsequent rhesus positive babies. This is called haemolytic disease of the newborn (HDN) and can cause anaemia and even death of the foetus. To prevent HDN, women were given anti-D after birth, to mop up any stray rhesus positive cells that may have prompted them to make damaging antibodies. If you already have the antibodies, anti-D is of no use to you. This policy has been very successful, but about 30 babies a year still die in the UK as a result of HDN. To reduce these potentially preventable deaths, rhesus negative mothers are to be routinely offered anti-D injections at 28 and 34 weeks of pregnancy. The treatment is derived from donated blood, which is screened for known viruses. As ever, it's a question of balancing the risks and most experts feel that it is worth having the injections.
· These answers are intended to be as accurate and full as possible, but should never be used as a substitute for visiting a doctor and seeking medical help. If you have a question for Dr Robinson, email drann@dircon.co.uk or write to her c/o The Health Editor, The Guardian, 119 Farringdon Road, London EC1R 3ER. She regrets that she cannot enter into personal correspondence.
