Editor,—We were pleased to see the publication on behalf of the UK Steering Group “Recommendations for the management of galactosaemia”.1 In particular, we were pleased to see the emphasis on the management of adult women and the prevention of osteoporosis. We have, however, some concerns about the advice on the use of Loestrin 20 (an oral contraceptive preparation containing 20 μg ethinyl oestradiol and a progestogen) for long term oestrogen replacement.

None of the combined oral contraceptive pills, such as Loestrin 20, are licensed for the prevention of osteoporosis, although until the more widespread use of hormone replacement therapy (HRT) preparations, many were widely used for this purpose. In addition to providing oestrogen, they have the advantage of being without prescription charge and are widely accepted, particularly by young adults.

There are disadvantages, however. The main one is the duration of therapy. Women taking combined oral contraceptive preparations receive only three weeks oestrogen out of four, which being extrapolated means that they receive 30 years replacement instead of 40. In women who are producing no oestrogen of their own, this difference may be important. We are also concerned that ethinyl oestradiol, as contained in combined oral contraceptive preparations, is not detected by standard hormone assays. Monitoring of oestrogen replacement is, therefore, dependent on suppression of follicle stimulating hormone and luteinising hormone, which does not allow for appropriate adjustment of oestrogen levels and may result in the woman receiving inadequate oestrogen. Women taking the combined oral contraceptive pill are also exposed to progestogens for longer in the cycle (21 days rather than 12 days) than women on HRT. In some cases, although not with the recommended Loestrin 20, this may also be at higher doses. Progestogens are reported to adversely affect the lipid profile in women receiving oestrogen replacement.

There are particular reasons for advocating the use of HRT rather than combined oral contraceptives in women with galactosaemia. Although it is recognised that the dose of lactose in combined oral contraceptive preparations is very small, it may be unacceptable to some patients. One method of delivery of HRT is via the transdermal patch, which avoids the ingestion of any exogenous lactose.

For these reasons, we believe that oestrogen replacement in the form of HRT preparations are preferable to combined oral contraceptive preparations in the long term management of women with galactosaemia.