Philip C. Hannaford

Prevalence and characteristics associated with use of hormone replacement therapy in Britain

Objective To describe trends in the prevalence of hormone replacement therapy (HRT) use among women living in Britain between 1981 and 1990, and to determine whether women who receive HRT are different from those who do not.

Oral contraception and eye disease: findings in two large cohort studies

AIM To investigate the relation between oral contraceptive use and certain eye diseases. METHODS Abstraction of the relevant data from the two large British cohort studies of the effects of oral contraception, the Royal College of General Practitioners’ (RCGP) Oral Contraception Study and the Oxford-Family Planning Association (Oxford-FPA) Contraceptive Study. Both cohort studies commenced in 1968 and were organised on a national basis. Between them they have accumulated over 850 000 person years of observation involving 63 000 women. RESULTS The conditions considered in the analysis were conjunctivitis, keratitis, iritis, lacrimal disease, strabismus, cataract, glaucoma, retinal detachment, and retinal vascular lesions. With the exception of retinal vascular lesions, there was no consistent evidence of important increases in risk of eye diseases in users of oral contraception. There was about a twofold increase in the risk of retinal vascular lesions in recent pill users in both studies (statistically significant only in the RCGP study). The increase was not limited to any specific type of lesion and may well reflect diagnostic bias. CONCLUSION Oral contraceptive use does not appear to increase the risk of eye disease, with the possible exception of retinal vascular lesions.

The effect of induced abortion on subsequent pregnancy outcome

Objective— To investigate the effect of induced abortion on the outcome of the next pregnancy.

Combined oral contraceptives and liver disease

Although some information is available about the risk of liver tumors associated with combined oral contraceptive use, little is known about the relationship with other hepatic problems. Data from two large long-term observational studies, the Royal College of General Practitioners (RCGP) Oral Contraception Study and the Oxford-Family Planning Association (Oxford-FPA) Study, were used to examine this issue. Observations accumulated over a period of up to 27 years were available for each study. The incidence of liver disease in each study was low. There was no evidence of an increased risk of serious liver disease overall among current or former pill users. The RCGP study found a modest increased risk of mild liver disease associated with oral contraceptive use which declined after four years of use and after cessation of use. This increased risk occurred in women who had used oral contraceptives containing more than 50 micrograms of estrogen.

Evidence-guided prescribing of combined oral contraceptives : Consensus statement

There is a need to balance the provision of safe and effective contraception against the desire to avoid interventions which might unnecessarily restrict the availability of combined oral contraceptives (COCs). In March 1996, an international group of recognised authorities in their field met to review the available evidence concerning the effects of COCs and the value of various screening procedures in pre-menopausal women. Current scientific evidence suggests only two pre-requisites for the safe provision of COCs: a careful personal and family medical history with particular attention to cardiovascular risk factors, and an accurate blood pressure measurement. Further assessment is required only if a relevant personal or family history is disclosed or the blood pressure is elevated. Only a small minority of women will require this further assessment.

The effect of induced abortion on subsequent fertility

Objective To investigate the effect of induced abortion on subsequent fertility.

Pregnancy following induced abortion: maternal morbidity, congenital abnormalities and neonatal death. Royal College of General Practitioners/Royal College of Obstetricians and Gynaecologists Joint Study.

Summary. In a prospective cohort study of the long‐term sequelae of induced abortion, a comparison is made between a group of 6418 women who had an induced abortion (cases) and a control group of 8059 women recruited with an unplanned pregnancy which was not terminated with an induced abortion (controls). The present paper reports on 729 cases and 1754 controls who had a post‐recruitment pregnancy. In general, prior induced abortion had no material effect on the rate of pregnancy‐related morbidity, nor on the rate of congenital abnormalities and neonatal death in the offspring. There was, however, a significant difference in two specific conditions. In the post‐index pregnancy in the cases there was an increased relative risk (RR 2·26) of the occurrence of urinary tract infection and a decreased risk (RR 0·25) of pregnancy‐related anaemia.

Combined oral contraceptives: Do we know all of their effects?

Combined oral contraceptives are undoubtedly popular. By the end of the 1980s, an estimated 63 million married women around the world were using this method of contraception. In Britain, perhaps 95% of all sexually active women have used the pill at some time before their 30th birthday. Commensurate with such widespread usage, huge amounts of money have been spent during the past 35 years investigating the health effects of this method of contraception. Since it appears that all of the potential risks and benefits have now been identified, can we divert resources from pill-related research into new areas of activity. While this proposition may be attractive to funding bodies, and other researchers competing for increasingly scarce resources, it ignores the fact that several major uncertainties remain concerning the safety of combined oral contraceptives.