Repository hosted by TU Delft Library

Home · Contact · About · Disclaimer ·

Early effect of a low dose (30 μg) ethinyl estradiol-containing triphasil® on vitamin B6 status. A follow-up study on six menstrual cycles

Publication files not online:

Author: Massé, P.G. · Berg, H. van den · Duguay, C. · Beaulieu, G. · Simard, J.M.
Institution: TNO Voeding Centraal Instituut voor Voedingsonderzoek TNO
Source:International Journal for Vitamin and Nutrition Research, 1, 66, 46-54
Identifier: 233596
Keywords: Aspartate aminotransferase · Oral contraceptive · Pyridoxal · Pyridoxal phosphate · Vitamin B6 status · Ethinylestradiol · Ethinylestradiol plus norgestrel · Norgestrel · Oral contraceptive agent · Pyridoxal · Pyridoxal 5 phosphate · Pyridoxine · Adult · Blood · Drug effect · Erythrocyte · Female · Human · Menstrual cycle · Metabolism · Nutritional status · Adult · Contraceptives, Oral, Hormonal · Erythrocytes · Ethinyl Estradiol · Ethinyl Estradiol-Norgestrel Combination · Female · Humans · Menstrual Cycle · Norgestrel · Nutritional Status · Pyridoxal · Pyridoxal Phosphate · Pyridoxine


The objectives of the study were to follow-up six artificial menstrual cycles induced by Triphasil® in order to determine: 1) the time of apparition of B6 metabolic side-effects, in the eventuality they occur, and 2) the existence or non-existence of a normalization process and if so, when it is initiated. The choice of this triphasic OC preparation was based on its current popularity among modern gynecologists. Among the selected twenty-three young women who had never used oral contraceptives (OC), fourteen consented to try a new contraceptive method. Their nutritional status including anthropometric, hematologic, biochemical and dietetic (including vitamin B6 intake) parameters was found to be adequate. A functional enzymatic test coupled to a direct measurement of vitamin B6 was employed to obtain a complete assessment of their vitamin B6 status. By using both approaches, only one case (7%) of deficiency due to OC was evidenced. This well-controlled study revealed that a short-term use of a relatively low dose estrogen-containing OC (30 μg) did not alter PLP concentrations in plasma and erythrocytes in the majority of our young subjects consuming adequate diets. However, a disturbance in vitamin B6 metabolism was detected. PL levels in both blood components have increased steadily and did not subside to pretreatment values at the end of the experiment. In conclusion, the single use of the PLP vitamer can be misleading as demonstrated by other investigators. To assess B6-status during oral contraception, in addition to a functional enzymatic test, it may be necessary to include the other aidehydic form of vitamin B6, to fully establish and comprehend hormone-induced adverse effects on this metabolism, particularly those of progesterone/progestin that have not yet been explored. Chemicals/CAS: Contraceptives, Oral, Hormonal; Ethinyl Estradiol, 57-63-6; Ethinyl Estradiol-Norgestrel Combination, 8056-51-7; Norgestrel, 6533-00-2; Pyridoxal Phosphate, 54-47-7; Pyridoxal, 66-72-8; Pyridoxine, 65-23-6