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Estradiol + dydrogesterone oral

Updated 2 Feb 2023 | Oestrogens and HRT


Oral formulations containing estradiol and dydrogesterone (continuous and sequential therapies)

Drugs List

  • dydrogesterone 2.5mg and estradiol 0.5mg tablets
  • dydrogesterone 5mg and estradiol 1mg tablets
  • estradiol 1mg tablets and dydrogesterone 10mg tablets with estradiol 1mg
  • estradiol 2mg tablets and dydrogesterone 10mg tablets with estradiol 2mg
  • FEMOSTON 1mg + 10mg tablets
  • FEMOSTON 2mg + 10mg tablets
  • FEMOSTON CONTI 2.5mg+0.5mg tablets
  • FEMOSTON CONTI 5mg+1mg tablets
  • Therapeutic Indications


    Replacement therapy for oestrogen deficiency symptoms
    Secondary prophylaxis of postmenopausal osteoporosis where risk of fracture

    All strengths
    Hormone replacement therapy (HRT) for oestrogen deficiency symptoms in postmenopausal women at least 6 months since last menses (sequential therapy) or 12 months after last menses (continuous therapy).

    Products containing at least 1 mg of estradiol
    Prevention of osteoporosis in postmenopausal women at a high risk of fractures and who are intolerant or contraindicated for drugs indicated for the prevention of osteoporosis.


    For initiation and continuation of hormone replacement therapy, the lowest effective dose should be used for the shortest duration.


    Continuous therapy
    One tablet daily taken continuously with no breaks between packs.

    Sequential therapy
    One tablet containing estradiol is taken daily For the first 14 days of the 28 cycle. Then during the following 14 days, one tablet containing estradiol and dydrogesterone should be taken. After the cycle finishes a new 28 day cycle begins immediately.

    Additional Dosage Information

    In women who are not taking hormone replacement therapy and who are amenorrhoeic, or women who switch from a continuous combined hormone replacement therapy, treatment may be started on any convenient day. In women transferring from a cyclic or continuous sequential HRT regimen, treatment should begin the day following completion of the prior regimen.

    For sequential therapy patients should take one tablet a day orally, according to the sequence indicated on the package.


    Suspected hormone dependent neoplasm
    Abnormal liver function test
    Acute hepatic disorder
    Breast cancer
    Deep vein thrombosis
    History of breast cancer
    History of thromboembolic disorder without anticoagulant therapy
    History of venous thromboembolism
    Oestrogen dependent neoplasm
    Recent arterial thromboembolic disorder
    Uncontrolled endometrial hyperplasia
    Undiagnosed gynaecological haemorrhage
    Venous thromboembolism

    Precautions and Warnings

    Body mass index above 30kg per square metre
    Family history of breast cancer
    Patients over 65 years
    Predisposition to thromboembolic disease
    Prolonged immobilisation
    Recent surgery
    Severe headache
    Cardiac impairment
    Diabetes mellitus
    Endometrial hyperplasia
    Epileptic disorder
    Glucose-galactose malabsorption syndrome
    Hepatic disorder
    History of endometrial hyperplasia
    History of thromboembolic disorder
    Lactose intolerance
    Renal impairment
    Uterine fibroids

    Risk of pancreatitis in individuals with hypertriglyceridaemia
    Assess family medical history prior to commencing treatment
    Exclude breast cancer before treatment
    Exclude oestrogen dependent neoplasm before treatment
    Contains lactose
    Do breast & pelvic exam. before & during treatment if clinically indicated
    Exclude pregnancy prior to initiation of treatment
    Abnormal and/or irregular bleeding should be investigated
    Advise patients of risks/benefits & review need for treatment regularly
    Advise patient of thromboembolic symptoms and to report them if they occur
    Advise patient that changes in their breasts should be reported to Dr/nurse
    Increased risk of VTE during travel involving >5hr immobilisation
    May interfere with certain laboratory measurements
    Discontinue 4 - 6 weeks before major surgery
    Advise patient to seek advice at first indications of pregnancy
    Discontinue at first signs of thrombophlebitis or thromboembolism
    Discontinue if first occurrence or worsening of migraine/severe headache
    Discontinue if jaundice or other evidence of hepatic impairment occurs
    Discontinue if pre-existing uterine fibroids increase in size
    Discontinue if significant rise in blood pressure occurs
    Advise patient not to take St John's wort concurrently
    Female: Not for contraception.Use non-hormonal contraception, if required
    Advise patient of increased risk of breast cancer vs benefits of HRT

    Hormone replacement therapy (HRT) should only be considered for patients whose symptoms adversely affect quality of life. An annual careful appraisal of the risks and benefits should be undertaken. When carrying out initial medical examinations of patients, ensure that investigations (including appropriate imaging tools, e.g. mammography) are carried out in accordance with currently accepted screening practices.

    There is little evidence regarding the use of HRT in premature menopause, but due to the lower level of absolute risk in younger women, the benefit to risk ratio may be more favourable for these women compared to older women. The overall evidence suggests an increased risk of breast cancer in women taking combined oestrogen-progestogen (and possibly also oestrogen-only HRT). This increased risk is dependent on the duration of HRT. The Women's Health Initiative study (WHI) and epidemiological studies have both reported an increased risk of breast cancer in women taking combined oestrogen-progestogen for HRT. This increased risk becomes apparent within 3 years of starting treatment but returns to baseline within a few (at most five) years after stopping treatment. HRT is associated with a 1.3 to 3 fold risk of developing venous thromboembolism. The occurrence of such an event is more likely in the first year of HRT than later.
    There is little evidence that combined oestrogen-progestogen or oestrogen-only HRT offers any protection against myocardial infarction in women with or without existing coronary artery disease. The relative risk of CAD during use of combined oestrogen-progestogen HRT is slightly increased. As the baseline absolute risk of CAD is strongly dependent on age, the number of extra cases of CAD due to oestrogen+progestogen use is very low in healthy women close to menopause, but will rise with more advanced age. HRT is associated with an up to 1.5 fold increase in risk of ischaemic stroke. The relative risk does not change with age or time since menopause. However, as the baseline risk of stroke is strongly age-dependent, the overall risk of stroke in women who use HRT will increase with age. Fluid retention may be experienced in patients taking oestrogens and thus patients with cardiac or renal dysfunction should be carefully observed. Additionally, as rare cases of increased of plasma triglycerides (leading to pancreatitis) have been reported in women taking oestrogen therapy, patients with pre-existing hypertriglyceridemia should be followed closely. Patients who require thyroid hormone therapy should have their thyroid function monitored regularly whilst on HRT. There is no evidence that HRT improves cognitive function. There is some evidence of increased risk of dementia in women who start using continuous combined or oestrogen-only HRT after the age of 65.

    Pregnancy and Lactation


    Hormone replacement therapy is contraindicated during pregnancy.

    Should pregnancy occur, treatment should be discontinued immediately.

    Oestrogens has been associated with cardiovascular defects, eye and ear abnormalities and hypospadias in the newborn when having been exposed to these in the womb. However, some studies have failed to find a relationship between oestrogens and cardiovascular defects (Briggs, 2015).

    Administration of gestagens during pregnancy does not warrant the termination of the foetus, but an ultrasound should be considered (Schaefer, 2015).

    Development alterations in the psychosexual performance of boys have been attributed to exposure to estradiol and progestogen in the womb. Males who have been exposed to estradiol and progestogen have demonstrated a trend to have less heterosexual characteristics and fewer masculine interests than males which have not been exposed to these hormones prenatally (Briggs, 2015).

    The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14 to 17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( ) or if this is unavailable at the backup site ( ).


    Hormone replacement therapy is contraindicated during breastfeeding.

    Estradiol has been used to suppress postpartum breast engorgement in patients who do not desire to breastfeed (Briggs, 2015).

    Hale (2014) suggests that although small amounts of estradiol passes in to breast milk, there seems to be little impact on the nursing infant. Use of oestrogens in the initial weeks of breastfeeding may reduce the volume of milk produced and its protein content, thus it is advisable women wait until breastfeeding is well established before taking oestrogens.

    The American Academy of Pediatrics classifies estradiol as compatible with breastfeeding (Briggs, 2015)

    Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
    Specialist advice is available from the UK Drugs in Lactation Advisory Service at


    Tablets should be taken continuously without a break between packs.

    If a dose has been forgotten, it should be taken as soon as possible. When more than 12 hours have elapsed, it is recommended to continue with the next dose without taking the forgotten tablet. The likelihood of breakthrough bleeding or spotting may be increased.

    Advise patients not to self-medicate with St John's Wort during HRT.

    Advise patients that changes in their breasts should be reported to a doctor or nurse.

    Advise patients to contact their doctor if they are aware of a potential thromboembolic symptom (e.g. painful swelling of a leg, sudden pain in the chest, dyspnoea).

    Advise patient to seek advise at the first signs of pregnancy.

    Patients should be advised of the increased risks of diagnosis of breast cancer versus the benefits of HRT, and the need to review treatment regularly.

    Encourage patients to participate in the national breast cancer screening programme and the national cervical cancer screening programme as appropriate for their age. Breast awareness should also be encouraged and patients advised to report any changes in their breasts to their doctor or nurse

    Side Effects

    "Spotting" bleeding
    Abdominal distension
    Abdominal pain
    Abnormal vaginal bleeding
    Allergic skin reactions
    Back pain
    Breakthrough bleeding
    Breast enlargement
    Breast pain
    Breast tenderness
    Cervical erosion
    Change in amount of cervical secretion
    Changes in libido
    Cholestatic jaundice
    Cystitis-like syndrome
    Deep vein thrombosis (DVT)
    Erythema nodosum
    Exacerbation of varicose veins
    Gallbladder disease
    Haemolytic anaemia
    Hypersensitivity reactions
    Increased risk of breast cancer
    Increased risk of endometrial cancer
    Increased size of uterine fibroids
    Intolerance to contact lenses
    Irregular menstruation
    Leg cramps
    Liver function disturbances
    Myocardial infarction
    Pelvic pain
    Peripheral oedema
    Peripheral vascular disorders
    Premenstrual-like syndrome
    Pulmonary embolism
    Steepening of corneal curvature
    Thromboembolic disorders
    Vaginal candidiasis
    Vascular purpura
    Venous thrombosis
    Weight changes

    Effects on Laboratory Tests

    The density of mammographic images is increased in patients taking HRT, especially oestrogen-progestogen combined treatment. This may adversely affect the radiological detection of breast cancer.


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: May 2017

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 3rd edition (2015) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 10th edition (2015) ed. Briggs, G., Freeman, R. Wolters Kluwer Health, Philadelphia.

    Joint Formulary Committee. British National Formulary. 73rd ed. London: BMJ Group and Pharmaceutical Press; 2017.

    Medications and Mothers' Milk, Sixteenth Edition (2014) Hale, T and Rowe, H, Hale Publishing, Plano, Texas.

    Summary of Product Characteristics: Femoston-conti 1mg/ 5mg film-coated tablets. Mylan Products Limited. Revised August 2016.
    Summary of Product Characteristics: Femoston-conti 0.5mg/2.5mg. Mylan Products Limited. Revised August 2016.
    Summary of Product Characteristics: Femoston 1/10mg. Mylan Products Limited. Revised November 2016.
    Summary of Product Characteristics: Femoston 2/10mg. Mylan Products Limited. Revised November 2016.

    US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
    Available. at:
    Estradiol Last revised: 11 April 2017
    Last accessed: 20 April 2017

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