Anti-Mullerian hormone in short girls born small for gestational age and the effect of growth hormone treatment.

Background Fetal growth restriction is thought to negatively influence reproductive function in later life. Serum anti-Müllerian hormone (AMH) is a marker of the primordial follicle pool. The objectives of this study were to evaluate the effect of being born small for gestational age (SGA) on serum AMH levels and to investigate the effect of growth hormone (GH) treatment on serum AMH levels in short SGA girls. METHODS Serum AMH levels were investigated in 246 prepubertal girls aged 3-10 years: 119 untreated short SGA and 127 healthy controls. Associations between AMH levels and clinical characteristics were analysed using multiple regression analyses. In addition, we investigated the effect of GH treatment on serum AMH levels in short SGA girls. RESULTS Serum AMH levels were similar in short SGA and healthy control girls (P= 0.95). In short SGA girls, AMH levels were not significantly influenced by birth weight standard deviation score (SDS), birth length SDS and gestational age, even after adjustment for age, height SDS and body mass index (BMI) SDS at sampling, socio-economic status and maternal smoking during gestation. Serum AMH levels did not change during 4 years of GH treatment in short SGA girls (P= 0.43). ConclusionS Serum AMH levels in prepubertal short SGA girls are similar to healthy controls, indicating that the follicle pool is not compromised due to SGA birth. GH treatment has no effect on AMH levels in short SGA girls.

Testis function in prepubertal boys and young men born small for gestational age.

BACKGROUND/AIMS: Some studies reported an impaired gonadal function in males born small for gestational age (SGA). We investigated Sertoli cell function by measuring serum inhibin B and antimullerian hormone (AMH) levels in prepubertal boys and young men born SGA in comparison with age-matched controls born appropriate for gestational age (AGA). METHODS: Inhibin B and AMH levels were determined in 73 prepubertal short SGA boys and in 72 age-matched AGA boys. In addition, 25 SGA boys were re-examined after 2 years of growth hormone (GH) treatment. Furthermore, inhibin B, AMH, testosterone, LH and FSH were studied in three groups of young men: 21 SGA men treated with GH, 15 SGA men with spontaneous catch-up growth and 25 young men born AGA. RESULTS: Prepubertal short SGA boys and AGA boys had similar inhibin B (87.3 and 78.2 ng/ml) and AMH levels (75.6 and 63.6 microg/l, respectively). GH treatment did not result in different inhibin B and AMH levels. In young SGA men, inhibin B, testosterone, LH and FSH levels were similar compared to young AGA men. AMH levels were higher in the young SGA men (p = 0.03). CONCLUSIONS: Being born SGA does not impair Sertoli cell function. Young men born SGA have a normal hypothalamic-pituitary-testis axis.

Food intake of children with short stature born small for gestational age before and during a randomized GH trial.

Parents of short children born SGA often report that their children have a serious lack of appetite and a low food intake. In this study we investigated food intake, by using a standardized 7-day food questionnaire, in 88 short SGA children before start of GH treatment. The intake was compared with the recommended daily intake (RDI) of age-matched children. We also compared the food intake of GH-treated children (n=62) with randomized controls (n=26) after 1 year of GH treatment. In addition, we evaluated the effect of food intake and GH treatment on body composition and serum levels of IGF-I, IGFBP-3 and leptin. Our study shows that caloric intake, fat and carbohydrate intake of short SGA children aged 5.9 (1.6) years was significantly lower compared to the RDI for age-matched children. One year of GH treatment resulted in a significant increase of caloric, fat, carbohydrate and protein intake compared to baseline. Compared to randomized controls, caloric, carbohydrate and protein intake increased significantly after 1 year of GH treatment. Short SGA children had significantly lower SDS scores for LBM, fat mass, skinfold (SF) and BMI compared to age-matched references. They also had significantly lower serum IGF-I, IGFBP-3 and leptin levels. GH treatment resulted in a significant increase of height, LBM, BMI, IGF-I and IGFBP-3 SDS and a significant decrease of SF SDS and leptin SDS. In conclusion, our study shows that short SGA children have indeed a lower food intake than age-matched controls. During GH treatment the food intake increased significantly compared to baseline in contrast to the randomized control group.

Reduced insulin sensitivity and the presence of cardiovascular risk factors in short prepubertal children born small for gestational age (SGA).

BACKGROUND: Epidemiological studies have shown that the metabolic syndrome, a combination of type 2 diabetes mellitus, hypertension, dyslipidaemia and a high body mass index (BMI), occurs more frequently among adults who were born with a low birth weight. Because insulin is thought to play a key role in the pathogenesis of this syndrome we investigated insulin sensitivity and risk factors for cardiovascular disease in short prepubertal children born small for gestational age (SGA). PATIENTS AND METHODS: Frequently sampled intravenous glucose tolerance tests (FSIGT) were performed in 28 short prepubertal children born SGA. Short stature was defined as a height < -2SD. SGA was defined as a birth length and/or a birth weight for gestational age < -2SD. Twelve short children born appropriate for gestational age (AGA) were used as controls for the FSIGT's results only. AGA was defined as a birth weight and/or birth length for gestational age > -2SD. In short SGA children, blood pressure (BP), fasting levels of serum free fatty acids (FFA), triglycerides (TG), total cholesterol (TC), high-density lipoprotein (HDL) cholesterol and low-density lipoprotein (LDL) were measured and compared to reference values. RESULTS: Mean insulin sensitivity (Si) level in short SGA children was significantly reduced to 38% of the mean Si level measured in short AGA controls (P = 0.004). Mean acute insulin response (AIR) was significantly higher in SGA children compared to short AGA controls (P < 0.001). Differences in Si and AIR between the two groups remained significant after adjusting for age and BMI (P < 0.001 and P = 0.003, respectively). The mean (SD) systolic BP SDS was 1.3 (1,1), being significantly higher than zero. Mean fasting serum levels of FFA, TC, TG, HDL and LDL were all within the normal range. However, 6 of the 28 SGA children had serum FFA levels above the normal range. Cardiovascular risk factors could statistically be represented in two clusters. Both clusters played a significant role in the development of insulin insensitivity (1/Si). CONCLUSION: Although the metabolic syndrome has been described in adulthood, our study showed that risk factors for the development of type 2 diabetes mellitus and cardiovascular disease are already present during childhood in short prepubertal children born SGA, suggesting a pretype 2 diabetes mellitus phenotype.

GH treatment and its effect on bone mineral density, bone maturation and growth in short children born small for gestational age: 3-year results of a randomized, controlled GH trial.

BACKGROUND: To investigate in a group of short children born small for gestational age (SGA), the effects of 3 years of GH treatment vs. no treatment on bone age (BA), height and bone mineral density (BMD). Also, to evaluate the influence of the severity of growth retardation at start and the GH dose on the gain in height. PATIENTS AND METHODS: The study design was an open-labelled, controlled multicentre GH study for 3 years. Non-GH-deficient (GHD) children (n = 87) were randomized to either a GH group (n = 61) or an untreated control group (n = 26). In addition, 12 SGA children had GHD (GHD group) and were treated in parallel. Both the GH and the GHD group were treated with a GH dose of 33 microg/kg/day. BMD was evaluated using dual energy X-ray absorptiometry (DEXA). In addition, data of our first GH trial in which short SGA children were treated with a GH dose of 66 microg/kg/day (n = 24) were used for comparison of height gain. RESULTS: In contrast to the control group, the GH group showed a significant increase in height (P < 0.001), as did the parallel GHD group. Bone maturation [delta bone age (BA)/delta calendar age (CA)] increased significantly during the first 2 years of GH treatment but slowed-down thereafter. The 3-year deltaBA/deltaCA ratio correlated significantly with the gain in height (r = 0.6, P < 0.001). At start, mean BMD SDS and mean BMAD SDS were significantly lower than zero. During GH treatment both increased impressively (P < 0.001). The gain in height of children with severe short stature at start (< or = -3.00 SDS), did not differ between those receiving either a GH dose of 33 or 66 microg/kg/day. CONCLUSION: Three years of GH treatment in short children born SGA results in a normalization of height during childhood. Also, bone maturation increased proportionately to the height gain. At start, mean values of BMD and BMAD were significantly reduced but normalized during GH treatment. We did not find an indication to treat very short SGA children (H SDS < or = -3.00) with a higher GH dose. We rather suggest to start GH treatment at an early age in order to achieve a normal height before puberty starts.