Failure of a pure progestogen contraceptive to affect serum levels of iron, transferrin, protein-bound iodine, and transaminase

Evaluation of iron deficiency in young women in relation to oral contraceptive use

BACKGROUND

The purpose of this study was to identify the optimal measures for diagnosing iron deficiency (ID) in oral contraceptive (OC) users and nonusers, and to estimate ID frequency in relation to OC use.

STUDY DESIGN

Conventional biomarkers of iron status - serum ferritin, iron, transferrin (Tf) and transferrin saturation (TfS) - were compared with serum soluble Tf receptor (sTfR) and the sTfR/log ferritin ratio (sTfR-F index). Two hundred two healthy menstruating white Italian women (aged 24+/-4.8 years) were analyzed. Serum ferritin concentrations <12 microg/L were considered as ID.

RESULTS

ID was detected in 29.7% (60/202) of the study women. Fifty-nine women were OC users (59/202, 29.2%). OC use did not significantly affect ID prevalence (p=.24). However, OC use markedly increased Tf in OC users, who had an odds ratio (OR) of 9.3 (CI 3.8-22.7, p<.001) for elevated Tf >330 mg/dL. No other iron status measure was affected by OC. Of the markers for ID adjunctive to ferritin, an elevated sTfR-F index >or =1.5 showed the best performance. Specifically in OC users, the elevated sTfR-F index had better sensitivity (81.0% vs. 33.3%), specificity (94.7% vs. 92.1%), efficiency (89.8% vs. 71.2%), positive predictive value (89.5% vs. 70.0%) and negative predictive value (90.0% vs. 71.1%) than a TfS <15%. Additionally, the sTfR-F index allowed the identification of low iron stores in 4.5% (9/202) of women with ferritin > or =12 microg/L.

CONCLUSION

Among healthy OC users and non-OC users, the sTfR-F index had the highest performance for diagnosing ID compared with other serum markers adjunctive to ferritin measurements, whereas sTfR by itself had a low sensitivity. We showed that neither the sTfR nor sTfR-F index was affected by third-generation OC use. The sTfR measurement is useful in the diagnosis of ID, especially in women using OC, where Tf and TfS tests may be misleading.

Sex-related differences in hematological values. A study on the erythrocyte and granulocyte count, plasma iron and iron-binding proteins in human transsexuals on contrasexual hormone therapy

Hematological data known or supposed to be influenced by individual sex hormones were evaluated in 18 untreated transsexuals (TS) and in 20 castrated or non-castrated TS on androgen and estrogen treatment, respectively. Profiting from a situation of clinically controlled hormonal sex-transformation it was tested, whether the circulating erythrocyte and granulocyte mass and iron metabolism are linked to a male and female sex-hormone constellation. The erythrocyte and granulocyte counts were significantly higher in untreated males and treated female-to-male TS than in untreated females and treated male-to-female TS. The unexpected finding of sex hormone-dependent granulocyte fluctuations was corroborated by parallel concentration changes of lactoferrin, a granulocyte-derived plasma protein. Iron metabolism as judged from plasma iron, total iron-binding capacity and serum ferritin was unaffected by sexual transformation. Plasma iron and the total iron-binding capacity did not differ significantly in untreated and treated TS of either type. The serum ferritin concentration, however, was significantly lower in untreated as well as in virilized females than in untreated and in feminized males, but was not significantly changed by long-term androgen or estrogen treatment. The present study demonstrates the potential of human transsexualism as a model for the study of sex-related biological processes.

Long acting contraceptives. Present status

Long acting injectable hormonal contraceptives are among the most effective fertility regulating agents developed; yet they are also among the most controversial because of animal data indicating a possible carcinogenic potential in several species. A critical analysis of these animal findings has revealed, in all instances, the existence of specific mechanisms not occurring in the human. For this reason, most national and international scientific bodies who have reviewed this issue have concluded that there are no toxicological reasons for not using long acting hormonal contraceptives. Long acting agents can be divided into 2 separate groups: those having a duration of action of one month, which are composed of a long acting oestrogen and a progestagen, and those lasting for several months which consist of only a progestagen. Among the injectable progestagen-only contraceptives tested, only 2 have so far reached the international market: depot medroxyprogesterone acetate (DMPA), which has been administered at 3- or 6-month intervals and norethisterone enanthate, which has been injected at intervals ranging between 2 and 3 months. The most important side effect observed with these 2 agents is a complete disruption of the menstrual bleeding pattern, leading - in some cases - to total amenorrhoea, which is more frequent with depot medroxyprogesterone acetate than with norethisterone enanthate. The latter, however, has a shorter duration of action with a higher pregnancy rate than the former. Other adverse reactions are rare and of no real importance. Metabolic effects with progestagen-only injectable preparations are, in general, mild and less marked than with combined oestrogen-progestagen formulations. Recent investigations have shown that the return of fertility following their use is delayed but in no way impaired. Monthly injectable oestrogen-progestagen combinations have been tested to a more limited extent and these agents are available only in a very few countries. Their main advantage over progestagen-only preparations is that they allow a reasonable menstrual bleeding pattern in the majority of cases. Their obvious disadvantage is that they contain a long acting oestrogen.

Effects of medroxyprogesterone acetate on serum lipids, protein, glucose tolerance and liver function in Thai women

Proteins (total, albumin, globulin and their subfractions), carbohydrate (intravenous glucose tolerance test), lipids (serum cholesterol, triglycerides and phospholipids), and liver function tests (alkaline phosphatase, lactic dehydrogenase and aspartate aminotransferase activities in the serum, bromsulphathalein retention test and serum bilirubin) were studied in 12 non-lactating healthy Thai subjects before, and subsequently at 3 weeks and 3, 6, 9 and 12 months after the initiation of treatment with injectable medroxyprogesterone acetate (150 mg I.M. every 90 days). Serum protein and lipid levels, and the results of liver function and I.V. glucose tolerance tests, remained unchanged in all subjects throughout the one-year study period. However, a significant and persistent increased insulin level was noted in all subjects, after initiation of the hormone treatment, during the first thirty minutes of intravenous glucose load. It is concluded that injectable medroxyprogesterone acetate used as a contraceptive agent does not interfere with glucose tolerance, lipid and protein metabolism, and that the liver function remains normal during its administration.

[Metabolic studies under administration of oral contraceptives. A review]

The use of oral contraceptives can produce changes in the metabolism of carbohydrates, lipids, proteins, vitamins, and minerals. Responsible for the alterations seems to be the used oestrogen- and gestagen derivative and not so much the type of the contraceptive. The most frequent findings are raised serum-glucose-, insulin-, and triglyceride levels; disturbances in protein-metabolism increase the risk of developing thrombosis and hypertonia. Little is known about the significance of oral contraceptives on the vitamin- and mineral metabolism--yet extreme deficiencies have not been observed so far. Oral contraceptives can become an extra risk factor when given to women with metabolic disturbances.

Variations in serum iron and total iron binding capacity with the time of intake of combined oral contraceptives

Serum iron and total iron binding capacity (TIBC) were estimated in 145 healthy subjects in the reproductive stage of life, using lyndiol and eugynone for a period of 1-72 months, and results were compared with those of 30 healthy individuals, of the same class, also in reproductive stage of life. Serum iron variation did not follow any clear pattern. TIBC increased in 80% of the subjects to a value equivalent to 3-110% of the mean control. There was also a clear increase observed in immunoelectrophoretic pattern of transferrin, following the use of oral contraceptives.