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Biomedical subjects

N Parera

Publications and source records attributed to N Parera.

9 recordsLinked to original sources
PubMed2006

A prospective trial comparing oocyte donor ovarian response and recipient pregnancy rates between suppression with gonadotrophin-releasing hormone agonist (GnRHa) alone and dual suppression with a contraceptive vaginal ring and GnRH.

BACKGROUND: Contraceptive treatment before gonadotrophin-releasing hormone agonist administration presents advantages in women with a tendency to hyper-response and simplifies donor-recipient treatment synchronization. This study compares response to gonadotrophin stimulation under hypophyseal suppression in oocyte donors with or without vaginal contraceptive pretreatment. METHODS: One hundred and ninety oocyte donors were recruited in a single centre and prospectively assigned to one of two treatment groups, according to the day of the week menstruation initiated: Group VC-, no prior vaginal contraceptive and Group VC+, prior vaginal contraceptive. RESULTS: VC+ patients presented a significantly higher cancellation rate, lower plasma estradiol levels and fewer follicles >12 mm on the day of hCG, versus the VC- group. Number of oocytes recovered was significantly lower in the VC+ group. All the cases of severe ovarian hyperstimulation syndrome (SOHSS) were in the VC- group. Pregnancy rates by embryo transfer to synchronic recipients were similar between VC+ and VC- (59.5 versus 57.9%, respectively). CONCLUSIONS: Vaginal contraceptive pretreatment resulted in a higher ovarian suppression, whereas SOHSS rate was lower than in donors who did not receive pretreatment. There were no differences in pregnancy rates between the two groups of synchronic oocyte recipients.

Adult↗
PubMed2001

Ultrasound-guided embryo transfer: immediate withdrawal of the catheter versus a 30 second wait.

It is essential to deposit embryos as gently as possible during IVF, avoiding manoeuvres that might trigger uterine contractions which could adversely affect the results of this treatment. The time during which the embryo transfer catheter remains in the cervical canal might be related to stimulation of contractions. This study investigates the influence that the time interval before withdrawal of the catheter after ultrasound (US)-guided embryo deposit might have on the pregnancy rate in patients under IVF cycles. A total of 100 women about to undergo transfer of at least two optimal embryos was studied. The women were prospectively randomized into two groups: (i) slow withdrawal of the catheter immediately after embryo deposit (n = 51); and (ii) a 30 s delay before catheter withdrawal (n = 49). The pregnancy rates for transfer in the two groups were 60.8 and 69.4% respectively, with no significant differences. There were no statistically significant differences in pregnancy rates between the two patient groups. The results indicate either that the waiting interval was insufficient to detect differences, or that the retention time before withdrawing the catheter is not a factor that influences pregnancy rate.

Adult↗
PubMed2000

Human chorionic gonadotropin and intravaginal natural progesterone are equally effective for luteal phase support in IVF.

This prospective randomized study compared human chorionic gonadotropin (hCG) and micronized transvaginal progesterone for luteal support in 310 in vitro fertilization (IVF) patients treated with leuprolide acetate and gonadotropins in a long protocol, and showing normal ovarian response. Both treatment groups were homogeneous for age, BMI, stimulation treatment and ovarian response. Pregnancy rates per embryo transfer were not significantly different (33.1% for the hCG group versus 38.7% for the progesterone group). For IVF patients with a normal response to stimulation under pituitary suppression, the use of hCG or progesterone for luteal support does not seem to have any effect on pregnancy rate. The choice of luteal treatment must balance medical hazard and patient convenience, as both therapeutic regimens seem equally effective.

Administration, Intravaginal↗
PubMed1997

Sexuality and contraception in adolescents from Barcelona, Spain.

STUDY OBJECTIVE: To describe the sexual behavior and contraception use among a sample of high school and vocational school adolescents in Barcelona, Spain. DESIGN: Cross-sectional study. METHODS: A random sample of 3139 students, aged 14 to 19 years, living in the city of Barcelona, were surveyed by means of an anonymous, self-administered questionnaire. SPSS/PC+ was used for statistical analysis. Significance criterion was set at 0.01. MAIN RESULTS: 13% of the students had previously participated in sexual intercourse; percentages between the sexes was equal. Frequency increased with age. Boys had their first experience at a significantly earlier age, but girls participated in sexual intercourse more often. The majority of adolescents used condoms as their primary contraceptive method; seven (3.3%) of the sexually active girls had been pregnant, and two (1%) boys had caused their partners to become pregnant. CONCLUSIONS: The rate of sexual activity among adolescents in Barcelona is low compared with those in both European and American studies. However, a higher rate of condom use is observed.

Adolescent↗
PubMed1996

Chronic illness and emotional distress in adolescence.

OBJECTIVE: The purpose of this study was to investigate emotional distress and suicidal ideation among adolescents with and without chronic illness. METHODS: Two groups were compared from the Barcelona Adolescent Health Survey (3,129 students aged 14-19 years) data base. The index group included 162 adolescents with chronic conditions (100 females and 62 males) including those with asthma, diabetes, seizures, or cancer. No differences in prevalence of emotional distress or suicidal ideation were found among the four categories of disease. The control group included 865 subjects (383 females and 482 males). No age differences were evident between the index and control groups. Chi-square and Student's t-test were used for intergroup comparisons, with the criterion value set at p < .01 to reduce the probability of type I error. Analyses were conducted separately by gender. RESULTS: Compared with controls, a significantly greater proportion of females with chronic illness reported emotional problems, feeling in a bad mood, feeling sad, believing nothing amused them, having suicidal thoughts, expressing depressive symptomatology, and having personal problems needing professional help. In contrast, no significant group differences were found for males. No gender differences were found regarding recent contact with a mental health specialist. CONCLUSIONS: Chronic illnesses were associated with substantive emotional distress and suicide ideation in females but not in males. Females with chronic conditions did not, however, seek mental health services more often than their non-chronically ill counterparts. This suggests serious shortcomings in identification of "at-risk" youth and effective outreach to this population.

Adolescent↗
PubMed1992

Indications for oocyte donation.

Donated oocytes were transferred on 92 occasions to 87 women without gonadal function and 5 with functional ovaries. Twenty-three pregnancies were established (25% pregnancy rate), 9 after transfer of fresh embryos in 30 synchronous donor and recipient cycles and 14 after transfers of frozen-thawed embryos in 62 asynchronous donor and recipient cycles. Twenty-two pregnancies were obtained in agonadal patients (25.3% pregnancy rate) and 1 in a gonadal woman (20% pregnancy rate). Pregnant women were younger than those who did not become pregnant, but the difference was not significant. The pregnancy rate was higher when intra-Fallopian transfer was performed (46%) as compared with intrauterine transfer (21.5%) and when micronized progesterone was given intravaginally (pregnancy rate 30.3%) as compared to intramuscularly injected natural progesterone in oil (pregnancy rate 22%). Twenty healthy infants have been born including one set of twins; four pregnancies miscarried.

Adult↗