Prevención del embarazo reiterado en adolescentes: una experiencia clínica exitosa / Prevention of repeated pregnancy in teenagers: a successful experience

INTRODUCCIÓN: el embarazo adolescente tiene consecuencias para la madre y su hijo/a. Además del riesgo propio de la gestación índice, ser madre en esta etapa vital predice la ocurrencia de otra(s) gestación(es) antes de cumplir 20 años, lo que aumenta aún más la vulnerabilidad de todo el grupo familiar. La evidencia actual señala que el inicio postparto inmediato de un método anticonceptivo de larga duración (LARC, por sus siglas en inglés: long acting reversible contraceptive) es la intervención más efectiva para prevenir el embarazo reiterado en adolescentes. OBJETIVOS: evaluar la estrategia de iniciar un LARC inmediato post parto en un hospital público de la región metropolitana de nuestro país. MÉTODOS: en el Hospital El Carmen Dr. Luis Valentín Ferrada de Maipú se realiza consejería en anticoncepción a todas las madres adolescentes y se les ofrece inicio de implante anticonceptivo previo al alta. Durante el 2015 el 53.4% de las puérperas adolescentes decidieron iniciar implante (Implanon ®) en forma inmediata. El 2017 se logró contactar a 92 pacientes de este grupo: un 90.3% se mantenía usando el mismo método. De las adolescentes que se lo habían retirado, todas reportaban uso de algún otro método anticonceptivo. En el grupo intervenido no hubo ningún nuevo embarazo, en el grupo control (sin anticoncepción postparto) se observÓ un 7% de gestaciones reiteradas durante el periodo evaluado. CONCLUSIONES: el inicio de un método LARC en el postparto inmediato parece ser una herramienta exitosa para reducir de la tasa de embarazo repetido en la adolescencia.

INTRODUCTION: adolescent pregnancy has consequences for the mother and her child. In addition to the risk of the index pregnancy, being a mother at this stage of life predicts the occurrence of other pregnancies before the age of 20, which further increases the vulnerability of the entire family group. Current evidence suggests that immediate postpartum initiation of long-acting reversible contraceptive (LARC) is the most effective intervention to prevent repeat pregnancy in adolescents. OBJECTIVES: to evaluate the strategy of starting an immediate postpartum LARC in a public hospital in the metropolitan region of our country. METHODS: at the Hospital El Carmen Dr. Luis Valentín Ferrada de Maipú, contraception counseling is given to all adolescent mothers and they are offered the start of a contraceptive implant before discharge. During 2015, 53.4% ​​of adolescent puerperal women decided to start an implant (Implanon ®) immediately. In 2017, 92 patients from this group were contacted: 90.3% continued using the same method. Of the adolescents who had withdrawn it, all reported use of some other contraceptive method. In the intervened group there were no new pregnancies, in the control group (without postpartum contraception) 7% of repeated pregnancies were observed during the evaluated period. CONCLUSIONS: the initiation of a LARC method in the immediate postpartum seems to be a successful tool to reduce the rate of repeat pregnancy in adolescence.

Histopathologic examination of the genital tract in rabbits treated once or twice with a slow-release deslorelin implant for reversible suppression of ovarian function.

A total of 13 rabbits were treated with a subcutaneous deslorelin long-term release implant (4.7 mg) to study the effect on ovarian function and histologic features of the uterus. Seven rabbits (group 1) were implanted with a slow-release deslorelin implant before onset of puberty for 273 days as a part of a previous study. After resumption of ovarian function had been confirmed, they were implanted again at the age of 430 days. Six adult rabbits (>177 days old; group 2) were implanted with a slow-release deslorelin implant for 273 days. Ovarian function before, during, and after treatment with the implant was assessed by measuring serum progesterone levels 10 days after a challenge injection of a short-acting GnRH (0.8 µg buserelin intramuscularly) on progesterone levels in peripheral blood. Values more than 4 ng/mL progesterone were considered to verify ovarian function. Animals in group 1 underwent ovariohysterectomy during the second treatment with the implant and the uteri, and ovaries were subjected to histopathologic examination. Endometrial hyperplasia and endometritis were observed in 5 of 7 animals. Nonatretic and atretic follicles at different developmental stages, but no active corpora lutea, were present in the ovaries. Ovariohysterectomy of group 2 animals was performed 2 to 12 months after implant removal. The histopathologic examination of the uterus and ovary of four animals neutered during induced pseudopregnancy showed no signs of uterine disorders. In two animals undergoing ovariohysterectomy 12 months after implant removal, endometritis was present. Their ovaries contained follicles at different developmental stages and corpora albicantia. Reversible suppression of ovarian function can be achieved in female rabbits by the use of GnRH slow-release implants administered before or after puberty. The findings of endometrial hyperplasia and endometritis in seven out of 13 rabbits treated once or twice with the implant may indicate that the development of age-related pathologies of the uterus cannot be prevented by the suppression of ovarian function with a long-acting GnRH implant.

Reversible estrous cycle suppression in prepubertal female rabbits treated with slow-release deslorelin implants.

The aim of this study was to examine the long-term effect of a 4.7-mg deslorelin GnRH analog implant on ovarian function in the prepubertal female rabbit. Seven female rabbits (group 1) were treated with the implant at the age of 60 days. The implant was inserted subcutaneously in the umbilical region. Two animals (group 2) were not treated and served as a control group. The vulva of all 9 animals was examined for the presence of typical cyclical changes, additionally the occurrence of mounting behavior was recorded. Ovarian function was checked by administration of a short-acting GnRH agonist to induce ovulation and pseudopregnancy (0.8 µg of buserelin per animal intramuscularly). Ten days after each treatment with buserelin, blood was collected for progesterone measurement to confirm pseudopregnancy. After implant insertion, the first blood collection (Day 10) was done without preceding induction of ovulation to screen for implant induced ovulation and pseudopregnancy. The implant was in situ for 273 days, and during this time span, 12 attempts of induction of ovulation were carried out in intervals of 21 days, beginning at the age of 81 days. Afterward, it was removed under local anesthesia and 3 further inductions of ovulation by the same scheme were conducted. The insertion of the implant led to the establishment of a pseudopregnancy in 2 of 7 animals; the remaining 5 animals did not show elevated progesterone values. Attempts to induce ovulation by administration of the short-acting GnRH analog while the slow-release GnRH analog implant was in place were not successful in treated animals, and progesterone concentrations were basal. The effect was reversible as ovulation could be induced in 2 subsequent cycles in all animals by the third induction of ovulation after implant removal. Induction of ovulation in control animals at the age of 110 and 131 days resulted in elevated progesterone levels after 10 days. No adverse side effects could be observed in implant-treated animals. The typical red coloration of the vulva could be seen in group 2 and after implant removal in group 1. The results suggest that in 5 of 7 rabbits, puberty was delayed by the treatment with the 4.7-mg deslorelin slow-release analog until the implant had been removed. In the other animals, the treatment induced an initial flare-up phenomenon. Afterward, the treatment could reversibly suppress ovarian function in all 7 treated animals.

Reversibility of germinative and endocrine testicular function after long-term contraception with a GnRH-agonist implant in the tom-a follow-up study.

A significantly reduced gonadotropin and testosterone secretion is a well-described result of long-term administration of GnRH agonists in the male dog and cat. To date, no data are available about the duration of efficacy and the reversibility of treatment-induced effects after long-term treatment with a 4.7 mg deslorelin implant. Seven healthy male European Shorthair cats (3.2 ± 0.5 kg, 1-6 years) were treated with a 4.7 mg deslorelin implant. Blood samples (testosterone, T), testicular volume, penile spines, and mating behavior were recorded once weekly. Considering T > 0.5 ng/mL as the biological endpoint, mean duration of efficacy was 78.8 ± 12.9 weeks (range: 61.7-100.7 weeks) with T concentrations increasing rapidly after the last T less than 0.1 ng/mL (basal) (P < 0.0001), and pretreatment T concentrations being reached after 3 weeks. Testicular volume rapidly increased after the first increase of T (P < 0.001) with pretreatment testicular volume being reached after 6.9 ± 3.4 weeks (5-11 weeks). "Normal" libido reoccurred 88.7 ± 12.4 weeks after treatment, and "normal" mating behavior was observed even later. Fertile matings occurred 7 to 42 weeks after the last T less than 0.1 ng/mL with a mean of 4.0 ± 0.0 kittens, and 13.6 to 47.6 weeks afterwards testicular histology revealed normal spermatogenesis. The present data confirm that the use of slow-release GnRH-agonist implants containing deslorelin in tomcats represents an effective and safe reversible alternative for long-term contraception; however, as number of animals is low, further fertility trials are recommended.