Effects of L-arginine on utero-placental circulation in growth-retarded fetuses.

BACKGROUND: To evaluate the effects of L-arginine (ARG) infusion, the nitric oxide as substrate, on the utero-placental circulation at third trimester. METHODS: Three groups of nine pregnant women each were infused i.v. with 30 g ARG, for 30 minutes. One group served as control, and the two remnants were composed by patients with intrauterine growth retardation with (IUGR-B) or without (IUGR-A) increased resistances in the utero-placental circulation. Changes of blood flow velocity waveforms of both uterine arteries and umbilical artery were recorded for 60 minutes. Blood pressure, serum nitrites/nitrates and growth hormone levels were also measured. RESULTS: No hemodynamic changes in utero-umbilical circulation were observed during infusion in any of the three groups. Considering the uterine arteries separately as placental and non-placental sided we found a significant decrease of non-placental side resistances in IUGR-B women. Indeed, the pulsatility index was lowered by 14%, in respect of baseline value. Serum nitrites/nitrates as well as serum growth hormone levels were significantly increased by ARG, in every woman, irrespective of the presence of fetal growth retardation. Blood pressure remained unaffected during infusion in every woman. CONCLUSIONS: These findings suggest that L-arginine infusion affects utero-placental circulation in patients with IUGR associated with increased uterine resistances. Such an action is specific and appears possibly to be mediated by a release of nitric oxide.

A comparative, randomized study of three different progesterone support of the luteal phase following IVF/ET program.

The use of luteal phase support has been demonstrated in patients undergoing IVF/ET in cycles stimulated after pituitary desensitization with gonadotrophin releasing hormone agonists. However, it is still not clear which is the most suitable kind of supplementation. This study was designed to compare the absorption and the efficacy of three different luteal support. We randomly administered progesterone i.m. (50 mg/day), human chorionic gonadotrophin (hCG) (2000 IU every three days), progesterone vaginal cream (100 mg/day) or nothing (controls) to 176 women treated for assisted procreation. We were not able to show any statistical differences for the percentage of pregnancy rate between groups. The serum progesterone (P) and 17-beta-estradiol (E2) and E2/P ratio levels of the luteal phase were compared with the control not supplemented group. All the treatments were able to increase significantly the luteal P values versus controls (p < 0.01). Moreover, vaginal cream and natural P im significantly decreased E2/P ratio (p < 0.05). Serum P levels were more steady with P vaginal cream than im injection. Vaginal cream for better bioavailability and acceptance appear the most suitable and comfortable method for luteal phase support.

Human decidua and in vitro decidualized endometrial stromal cells at term contain immunoreactive corticotropin-releasing factor (CRF) and CRF messenger ribonucleic acid.

CRF, a hypothalamic neurohormone, has been shown to be present in several tissues outside the brain. During pregnancy, both fetal (placental trophoblast, chorion, and amnion) and maternal (decidua) intrauterine tissues contain immunoreactive CRF. A paracrine/autocrine role of CRF as a regulator of hormonogenesis in human placenta and decidua has been suggested. The expression of CRF mRNA in human decidua was demonstrated in the present study by Northern blot analysis and was found to be higher in specimens collected at term than in those collected during the first and second trimesters of gestation. Furthermore, the presence of CRF was detected immunocytochemically in cultured decidual cells isolated from term decidua as well as in endometrial stromal cells decidualized in vitro by treatment with a mixture of medroxyprogesterone acetate, estradiol, and relaxin. These results indicate that human decidua is an intrauterine extrahypothalamic source of CRF in the maternal compartment and offer new tools to explore the in vitro decidualization processes and the regulation of CRF release from decidual cells.

Reduced spinal bone density in young women with amenorrhoea.

To assess the influence of diminished oestrogen production on bone density, we studied 23 amenorrhoeic women and 20 controls (age range 16-29 years) divided into four groups: group 1: 6 patients with idopathic hypogonadotrophic hypogonadism with primary amenorrhoea (IHH); group 2: 5 patients with delayed puberty owing to thalassaemia major (TM); group 3: 12 patients with secondary hypothalamic amenorrhoea (HA); group 4: 20 women with normal menses (controls). Secondary sexual characteristics had developed in all except the women with TM. Groups 1 and 2 had never menstruated and group 3 had been amenorrhoeic for 6 months to 3 years. The control group was studied during the follicular phase of the cycle. None of the patients were taking oestrogens at the time of observation. Plasma concentrations were determined for 17 beta-oestradiol (E2), deidroepiandrosterone sulphate (DHEA-S), cortisol (F), prolactin (PRL), thyroid hormones (T3 and T4), and gonadotrophins (LH and FSH). Spinal bone mineral density (BMD g/cm2) was assessed by dual photon absorbiometry. BMD (mean +/- 1SD) was reduced in the patients (group 2: 0.920 +/- 0.95; group 1: 0.980 +/- 0.94; and group 3: 1.037 +/- 0.75) as compared with the controls (1.290 +/- 0.95) (P less than 0.01). In the three groups of patients, plasma E2 levels were lower than 50 pg/ml and were positively correlated with the BMD. As expected, plasma gonadotrophin levels were highly and significantly reduced (P less than 0.01) in the patients, compared with that of the controls. These results suggest that reduced spinal BMD in hypogonadic women may be related to the lack of oestrogenic influence on bone metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)