[New perspectives for an old problem: premature labor]. / Nuevas perspectivas para un problema antiguo: el trabajo de parto pretérmino.

Preterm birth has been and continues to be one of the most serious problems in Obstetrics. It is the most common cause of neonatal death, and morbidity in surviving infants. The presence of bacterial vaginosis, and other genital infections is associated with increased risk of preterm labor. Cytokines promote the release of prostaglandin, and have been implicated as cause of uterina activity. Recently, new methods of detection as transvaginal ultrasonography, and measures of cervical fetal fibronectin have been acclaimed as useful to detect the problem. Atosiban, cytokines, glyceril trinitrate, and many others agents have been proposed as treatments and are under investigation. Such drugs, will allow an effective management of preterm labor with lower side effects. Antenatal TRH administration cannot be recommended for widespread clinical use. However, the antenatal administration of corticosteroids to fetuses at risk of preterm delivery include not only a reduction in the risk of respiratory distress syndrome but also a significative reduction in intraventricular hemorrhage mortality.

[Methods of sex selection. A new method for preventing genetic diseases]. / Métodos de selección del sexo. Una nueva forma de prevención de enfermedades genéticas.

Determining sex of offspring has been a subject of intense interest for the public and professional community. Although methods of selecting sex before concepts are not entirely reliable, couples could satisfy their wishes for the size and composition of their family and the children might benefit by being wanted. On the other hand, the ability to selectively separate X from Y chromosome-bearing spermatozoa and use the X spermatozoa to preferentially produce female offspring; could be reduce, or may even eliminate, the probability of conceiving affected males of X-linked diseases.

[Peri-conception use of folic acid in the prevention of neural tube defect: current concepts]. / Uso periconcepcional de ácido fólico en la prevención de defectos del tubo neural: conceptos actuales.

The incidence of neural tube defects (NTDs) is about 1.3 cases per 1000 live births. The higher incidence of NTDs occurs among certain ethnic groups, and geographic areas. The fetal morbimortality is high and the treatment for those babies who live is expensive with pour quality of live. It is unclear what biochemical mechanism involving folate explain the relationship of this vitamin to the pathogenesis of NTDs. However elevated concentrations of homocysteine or decreased methionine concentrations could be interfere with closure of the neural tube. The pharmacologic periconceptional intake of 0.4-4.0 mg/day of folic acid reduces the risk of occurrent NTDs by approximately 40-75%. A relatively high dietary intake of folate may also reduce the risk.

[Effect of prepuberal gonadectomy in partial androgen resistance syndrome]. / Efecto de la gonadectomía prepuberal en el Síndrome de Resistencia Parcial a los Andrógenos.

The androgen resistance syndrome, is a dominant and recessive linked to X disorder, with clinically heterogenous manifestations. Reported case. A 17-years patient with primary amenorrhoea and genital ambiguity. Bilateral inguinal herniplastia and probable gonadectomy were performed at 14-months-old. His cariotipe was male 46,XY and the hormonal determinations showed the presence of hypergonadotropic hypogonadismo. The congenital adrenal hyperplasia (deficiency of 21-hidroxilase) was discarded. In the partial androgen resistance syndrome, the prepuberal gonadectomy avoid a progresive virilization of the external genitals. However, the estrogenic hormonal replacement is mandatory.

[Urologic lesions in gynecologic and uro-gynecologic surgery. Two years of hospital experience]. / Lesiones urológicas en la cirugía ginecológica y uroginecológica. Dos años de experiencia institucional.

We are reporting the most frequent urologic injuries of the gynecologic and urogynecologic surgeries at the National Institute of Perinatology in Mexico City. From the period of March 1993 to February 1995. There were performed 3,452 surgeries. Of this, 2,971 were gynecologic and 481 urogynecologic cases. We found 20 patients with injury to the inferior urinary tract. The most frequent type of injury found was by puncture and blunt, in eight cases respectively and cutting in four. The transoperatory diagnostic of injury was performed in 17 patients and in three few days after. The late complications of the injury was urethral vaginal fistula in two, one vesicovaginal communication and one ureterovaginal, one stone formation and one transurethral catheter retention. The more affected organ was the bladder in 18 cases, urether and urethra. The injury to the inferior urinary tract represents 4.15% of the urogynecologic surgical complications, and 0.67% of the gynecological ones. The main aspect in the prognosis of the injury to the inferior urinary tract, is the early diagnostic during the surgical procedures.