Progestogens oral contraceptives

Hormones. Oestrogens, progestogens and androgens suppress lactation in high dose. Oestrogen/ progestogen oral contraceptives are present in amounts too small to be harmful but may suppress lactation if it is not well established. 

Combined oestrogen/progestogen oral contraceptives may both suppress and enhance cancers (see pp. 719, 723). 

Combined oestrogen-progestogen oral contraceptives have been extensively used since 1956. The principal mechanism is inhibition of ovulation (4, above) through inhibition of gonadotrophin secretion from the h3 othalamus. In addition the endometrium is altered, so that implantation is less likely (7, above) and cervical mucus becomes more viscous and impedes the passage of the spermatozoa (5, above). 

Woutersz, T. B. (1975) Profile of a new low dose combination estrogen and progestogen oral contraceptive A review of nine clinical studies. J. reprod. Med., 15, 87. 

Table 1. Low Dose Monophasic Estrogen—Progestogen Combination Oral Contraceptives Marketed in the United States...

The synthesis of Lp(a) can be influenced by hormones, as is reported by Albers et al. (A7), who observed a reduction of Lp(a) concentrations in nor-molipidemic postmenopausal women treated during 6 weeks with the anabolic steroid stanazolol. The same effect was reported for norethisterone (FI) and danazol (Cl2). Exogenous estrogens, as used in treatment of postmenopausal complaints and in oral contraceptives, induce a decrease of Lp(a) (D9, H27, K13, KAO, L21, S37). This effect is dose-related and dependent on Lp(a) levels before treatment (F2). Watanabe (W9) investigated the influence of progestogen (alone) and detected a decrease of Lp(a) during treatment. 

Since the development of the oral contraceptive steroids in the 1960s, various steroids and procedures have been used. Synthetic steroids are now used since their half-hves in the body are longer than the natural steroids. Combined oestrogen-progesterone contraception involves taking one piU each day which contains a synthetic progestogen plus an oestrogen. The pill is taken for 21 dyas, with a break for... 

Combined oral contraceptives are less likely to be associated with irregular vaginal bleeding than progestogen-only contraceptives. However, they are... 

Levonorgestrel is a progestogen derivative. It is found either in combined oral contraceptives coupled with an oestrogen derivative or alone in progestogen-only contraceptives. 

Q64 Initiating carbamazepine therapy in a patient receiving oral contraceptives decreases the contraceptive effect. Carbamazepine decreases the metabolism of oestrogens and progestogens. 

Corbamazepine interacts with oral contraceptives. Corbamazepine increases the metabolism of oestrogens and progestogens resulting in a decrease in the plasma concentration of oestrogens and progestogens. This in turn brings about a decrease in the contraceptive level provided. 

Chlormadinone Synthetic progestogen Menstrual disorders. Oral contraceptive... 

Ethynodiol diacetate Synthetic progestogen Component of many combined oral contraceptives. Progesterone replacement therapy... 

Norethisterone Synthetic progestogen Abnormal uterine bleeding. Endometriosis, component of some oral contraceptives and in hormone replacement therapy... 

Progestogens have a high affinity for sex hormone-binding globulin. Natural progesterone is rapidly metabolized in liver and can therefore not be given orally. In oral contraceptives synthetic... 

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