Sex hormone-binding globulin during puberty in normal and hyperandrogenic girls.

Human sex hormone-binding globulin (SHBG) regulates the cellular bioavailability of SHBG-bound steroid hormones. Subtle decreases in plasma SHBG levels during puberty have a perceptible effect on the androgen-estrogen balance. This SHBG decrease is more pronounced in girls with premature pubarche who are at risk to develop functional ovarian hyperandrogenism as well as insulin resistance syndrome. Insulin is a potent inhibitor of SHBG production in the liver, and there is now evidence that SHBG is a marker of hyperinsulinemia and insulin resistance that can be associated in both obese and non-obese patients with polycystic ovary syndrome. Therefore, low SHBG could be a useful tool for identifying presymptomatic individuals with diabetes mellitus type 2 including those with androgen disorders.

Differential effects of insulin and insulin-like growth factor I on the production of plasma steroid-binding globulins by human hepatoblastoma-derived (Hep G2) cells.

Changes in the plasma levels of corticosteroid-binding globulin (CBG) and sex hormone-binding globulin (SHBG) from birth to adulthood suggest that growth factors might influence clearance and/or hepatic secretion of CBG and SHBG in humans. The effects of insulin-like growth factor I (IGF-I) and insulin on CBG and SHBG synthesis by a clone of human hepatoblastoma-derived (Hep G2) cell lines were therefore investigated. The results showed that the immunoconcentrations of CBG and SHBG, as well as total protein concentration in culture medium from Hep G2 cells, were decreased by IGF-I and insulin. However, although the CBG-to-total protein ratio was decreased dose dependently by IGF-I and insulin, IGF-I and insulin did not dose-dependently decrease the SHBG-to-total protein ratio. The steady state levels of CBG and SHBG messenger RNAs (mRNAs) were reduced dose dependently by IGF-I with a half-effect at 5.4 +/- 1.9 and 4.6 +/- 1.6 nmol/L, respectively, and by insulin with a half-effect at 4.3 +/- 1.1 and 4.3 +/- 1.4 nmol/L, respectively. The maximum inhibitory effect of IGF-I on CBG mRNA level was 48 +/- 17% of control values and 60 +/- 13% for SHBG mRNA level. The changes in CBG mRNA levels were quantitatively similar to the changes in CBG immunoconcentration in the Hep G2 medium. In contrast, the inhibitory effects of insulin were only 17 +/- 8% and 31 +/- 12% of control values on CBG and SHBG mRNAs and 37 +/- 4% and 43 +/- 4% on CBG and SHBG concentrations, respectively. These results demonstrate that IGF-I reduces CBG and SHBG production by Hep G2 cells by decreasing mRNA steady state levels. The discrepancy between the inhibitory effects of insulin on CBG and SHBG mRNAs and protein secretion suggests that insulin exercises its inhibitory effects mainly on the mechanism(s) of translation and/or excretion of CBG and SHBG. The respective effects of IGF-I and insulin in the regulation of CBG and SHBG levels during fetal life and pubertal development in humans merit further study.

[Antenatal surveillance and risks of prematurity and fetal growth retardation]. / Surveillance anténatale et risques de prématurité et d'hypotrophie foetale.

The essential aim of this work was to investigate the relationship between antenatal care and preterm delivery or low birth weight. This study has been done by means of a case-control survey carried out among 435 women who delivered in 4 Maternity Hospitals in Aix-en-Provence-Pertuis area, between November 20th, 1987 and September 30th, 1988. Cases consisted of 124 women having delivered single livebirths before 37 weeks' gestation and 69 women having delivered, at term, single livebirths weighting less than 2,500 g. Controls were 242 women who delivered normal single livebirths. Results showed that, within the geographic area of the study, low birth weight and preterm delivery rates were respectively 6% and 5.4%. Antenatal care was generally according to medical profession recommendations: average number of visits: 7.9; first visit achieved, for 98.8% of women, within first trimester; intervention of a specialist in 97.1% of pregnancies; average number of ultrasound examinations: 3.5. Only mothers of low birthweight infants had more often an inadequate antenatal care (OR = 2.63, 95% confidence interval: 1.22-5.70). The risk factors for low birth weight were: previous history of preterm and/or low birth weight delivery, single marital status, low lever father's education, smoking during pregnancy, no contact with maternity team and for preterm delivery: previous history of preterm and/or low birth weight delivery, complications during the penultimate pregnancy, hypertension, metrorragies. These results suggest that it seems unlikely, in the future, to decrease unfavorable pregnancy outcomes by increasing antenatal care.

[Evaluation of the effects of a support campaign on exclusive breast feeding at 1 month]. / Evaluation des effets d'une campagne de soutien à l'allaitement exclusif au sein à un mois.

The aim of this study was to evaluate the effects of a support campaign on exclusive breast-feeding at one month postpartum among women having chosen breast-feeding. The study population consisted of all women (n = 657) having delivered in the Maternity Hospital in Pertuis (Area of Vaucluse-France) between January 1, 1987 and December 31, 1988. The first 151 women belonged to the control group not submitted to interventions while the following 506 composed the groups submitted to interventions. Interventions mainly aimed at providing information to women, supporting them after delivery, raising the awareness of their environment and educating Health professionals. Mothers were interviewed at the maternity and at their home one month later. Results showed that interventions significantly increased the number of women breast-feeding at one month (66% vs 52%-p less than 0.01) and reduced physical and medical problems related to breast-feeding (51% vs 60%-NS). To resolve these problems, Health professional education particularly appeared efficacious. The mothers' planned duration of breast-feeding was not significantly changed showing that actions were well conducted, as we wished, in the sense that the choice of mothers was respected. The greatest benefit was seen among the lowest social class (p less than 0.05), the less educated (p less than 0.01), and Maghrebin women (p less than 0.01).