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L Bahamondes

Publications and source records attributed to L Bahamondes.

At least 19 recordsLinked to original sources

The in vitro effect of levonorgestrel on the acrosome reaction of human spermatozoa from fertile men.

The objective of the study was to evaluate the effect of levonorgestrel (LNG) on the occurrence of acrosome reaction (AR) of capacitated spermatozoa from fertile men. A total of 20 semen samples from four fertile men were evaluated. The spermatozoa were separated by swim-up, and subsequently incubated for 20 h under capacitating conditions. Capacitated spermatozoa were exposed to three different concentrations of LNG (200, 400 and 800 ng/mL), follicular fluid (20% v/v), and ethanol or human tubal fluid medium (HTF) as a control. The AR rate and the ratio of live to dead spermatozoa were assessed after 15 and 30 min of incubation at 37 degrees C and 5% CO(2). The different treatments were compared with follicular fluid and HTF medium as positive and negative controls. The main results showed that the AR rate after 15 min of exposure was not affected by LNG and was significantly higher with follicular fluid than with all the other treatments. At 30 min of exposure, the three LNG concentrations induced a greater rate of AR than the HTF and a trend of higher AR rate with greater concentration was observed. Follicular fluid induced a significantly higher rate of AR than the other treatments. In conclusion, the addition of LNG in vitro to capacitated human spermatozoa is associated with a dose-dependent increased rate of AR, but such increase was not as great that induced by follicular fluid.

Acrosome↗

Delayed first injection of the once-a-month injectable contraceptive containing 25 mg medroxyprogesterone acetate and 5 mg estradiol-cypionate: effects on cervical mucus.

The objectives of this study were to assess whether women who were administered the first injection of the once-a-month contraceptive containing estradiol cypionate and 25 mg depot-medroxyprogesterone acetate (MPA+E(2)C) on Day 7 of their menstrual cycle (delayed injection) exhibit the same degree of cervical mucus changes as women who receive it on Day 5 of their menstrual cycle. This was a multicenter, randomized, controlled clinical trial. A total of 158 women, aged between 18 and 38 years (inclusive), who, were willing to use MPA+E(2)C as their contraceptive method participated in the trial. Participants received a MPA+E(2)C injection on Day 5 (control group, n = 41) or Day 7 (delayed-injection group, n = 117) of their menstrual cycle. Participants who received MPA+E(2)C on Day 5 of their menstrual cycle (control group) exhibited fair or poor mucus quality and poor sperm penetration. Of those women who received MPA+E(2)C on Day 7 of their menstrual cycle (delayed-injection group), 3 (3%) showed good mucus or good sperm penetration at some time point during follow-up. It is possible to conclude that the first injection of MPA+E(2)C given on Day 7 of a menstrual cycle does not provide the same degree of inhibition of mucus quality and sperm penetration as that observed if it is administered on Day 5. However, the theoretical risk of pregnancy after receiving MPA+E(2)C on Day 7 would be expected to be low.

Adult↗

Comparison of weight increase in users of depot medroxyprogesterone acetate and copper IUD up to 5 years.

The objective of this study was to evaluate retrospectively the weight variation in long-term users of depot medroxyprogesterone acetate (DMPA) compared to users of the TCu380A intrauterine device (IUD). A cohort of 206 healthy women allocated in two groups of 103 women according to the contraceptive method used was evaluated through 5 years. Each user of DMPA was paired with an IUD user by age (+/- 1 year) and weight (+/- 1 kg) at the beginning of the study. Weight was evaluated yearly during 5 years. The mean age at the beginning of the study was 33.1 years in both groups, and the mean weight was 59.4 kg in the IUD users and 60.4 kg in the DMPA group. Both cohorts of women presented significant weight increase at the end of the 5 years of observation (p < 0.001). However, DMPA users presented higher weight increase when compared to IUD users from the second through the fifth year of observation. The DMPA users increased weight by 4.3 kg during the 5 years, and IUD users increased 1.8 kg. In conclusion, DMPA users had a significantly higher weight increase when compared to IUD users. In addition, this cohort of women increased weight throughout the 5 years with the use of DMPA or IUD.

Adult↗

Delayed first injection of the once-a-month injectable contraceptive containing 25 mg of medroxyprogesterone acetate and 5 mg of E(2)-cypionate: effects on ovarian function.

OBJECTIVE: To assess whether women who were administered the first injection of DMPA+E(2)C on day 7 of their menstrual cycle (delayed injection) exhibit the same degree of ovarian suppression as women who receive it on day 5 of their menstrual cycle. DESIGN: Multicenter, randomized controlled trial. SETTING: Reproductive health clinics. PATIENT(S): Women aged between 18 and 38 years (inclusive) willing to use DMPA+E(2)C as their method of contraception. INTERVENTION(S): Participants received a DMPA+E(2)C injection on day 5 (control group, n = 41) or day 7 (delayed-injection group, n = 117) of their menstrual cycle. MAIN OUTCOME MEASURE(S): Ovarian activity and follicular development determined by serial serum progesterone levels and vaginal ultrasound. RESULT(S): Participants who received DMPA+E(2)C on day 5 of their menstrual cycle (control group) exhibited no more than limited follicular growth (no follicle >16 mm). Of those women who received DMPA+E(2)C on day 7 of their menstrual cycle (delayed-injection group), 21 (18%) showed some follicular growth, of whom 4 (3%) ovulated. CONCLUSION(S): The first injection of DMPA+E(2)C given on day 7 of a menstrual cycle does not provide the same inhibition of ovarian activity as that observed when it is administered on day 5 of the menstrual cycle.

Adolescent↗

Forearm bone density in long-term users of oral combined contraceptives and depot medroxyprogesterone acetate.

OBJECTIVE: To compare the bone mineral density of users of combined oral contraceptives (OC) or depot medroxyprogesterone acetate (depot-MPA) with women who have never used a hormonal contraceptive method. DESIGN: Cross-sectional study. SETTING: Academic tertiary-care hospital. PATIENT(S): A total of 189 women, aged 30 to 34 years old, were allocated to three groups: 63 who had used OC for at least 2 years; 63 who had used depot-MPA for at least 2 years; and 63 control women who had never used hormonal contraceptives. INTERVENTION(S): Each woman's bone mineral density (BMD) was evaluated at the distal and ultradistal section of the radius of the nondominant forearm by the use of single x-ray absorptiometry. MAIN OUTCOME MEASURE(S): We obtained BMD measurements for each participant. RESULT(S): Independent of the period of use and the section of the forearm studied, we found no difference in BMD for OC or depot-MPA users when compared to women who had never used hormonal contraceptive methods. In addition, BMD was similar between OC users and depot-MPA users. The multiple linear regression analysis showed that the variables associated with BMD were weight, number of pregnancies, and the woman's occupation. CONCLUSION(S): Women aged 30 to 34 years who have used OC or depot-MPA have similar BMD as control women. These findings suggest that the use of OC or depot-MPA does not affect the BMD of women in this age group.

Absorptiometry, Photon↗

Evaluation of human sperm membrane integrity using the water test and the hypoosmotic test.

The objective of the study was to compare the water test and the hypoosmotic test (HOS) in the assessment of the human sperm membrane. A total of 686 semen samples from human male donors were subjected to water and HOS tests after routine semen evaluation. The mean percentage of swollen spermatozoa was 71.8 +/- 9.6% in the HOS test and 67.8 +/- 9.4% for the water test; these values were not statistically different. The correlation of coefficients between the water test and the HOS test was highly significant whether the values for the HOS test were higher or lower than 60% (P < 0.001). A poor correlation was obtained when the two tests were compared for sperm counts either higher or lower than 20 x 6 ml-1 and when the results for both tests were compared with the percentage of eosin-Y staining spermatozoa. A poor correlation was also obtained when the results of each test were compared with eosin-Y staining spermatozoa in normal and abnormal semen samples. The coefficient of regression between the two tests showed a high correlation (P < 0.001). In conclusion, even though a high correlation between the HOS test and water test was observed in this study, it is not possible to recommend assessment of sperm membrane integrity using the water test and the consequent replacement of the HOS test in routine practice. Further studies are necessary to establish the best test for sperm vitality.

Cell Membrane↗

The effect upon the human vaginal histology of the long-term use of the injectable contraceptive Depo-Provera.

The objective of the study was to evaluate the effect of long-term use of the injectable contraceptive depot medroxyprogesterone acetate (DMPA) on human vaginal histology. Twenty premenopausal women currently using DMPA as a contraceptive method for two and three years were compared with 20 regularly menstruating women, who never used Depo-Provera and/or other kind of hormonal contraceptive in the last 6 months prior to the study. Subjects and controls were matched by age (+/-1 year), body mass index (kg/m2) (+/-1.0), number of pregnancies (+/-1), age at first intercourse (+/-1 year), years of sexual activity (+/-1 year), and number of partners during their life (+/-1). Vaginal biopsies were performed in users at 90+/-7 days after the last injection and in nonusers at day 20-25 of the menstrual cycle. In addition, at the day of the biopsy a blood sample was collected to measure estradiol (in all women) and DMPA in users. The level of serum estradiol was significant lower in Depo-Provera users than in controls (p < 0.001). The thickness of the vaginal epithelium was not smaller among DMPA users than among controls, the mean count of Langerhans cells per mm of epithelium were almost identical in both groups, and no significant differences were found on the vaginal maturation indices. In conclusion, the use of Depo-Provera between two and three years did not affect vaginal thinning of the epithelium, Langerhans cell count or maturation index.

Adult↗

Acceptability and performance of the levonorgestrel-releasing intrauterine system (Mirena) in Campinas, Brazil.

The objectives of this study were to evaluate the acceptability of the LNG-IUS Mirena(R), when offered as an additional option in a free choice context, and to evaluate the possibility of using this method in women with increased bleeding wanting an IUD and in copper IUD users requesting removal of the device for bleeding problems. A total of 256 women chose Mirena and were accepted into the study during the enrollment period. This represents 23.3% of all new acceptors of contraceptive methods in the clinic during the same period. Discontinuations were fairly evenly distributed among expulsion, bleeding changes, pain, and personal reasons. Bleeding changes were decreased bleeding, oligomenorrhea or amenorrhea. Comparing the performance in the group of women who chose the LNG-IUS as a first option with those having heavy bleeding, the only difference found was a higher expulsion rate in the group with bleeding problems. No pregnancies occurred and continuation rate was slightly over 75% in the total sample and in both groups. The characteristics of the LNG-IUS (Mirena) allow predicting that this method can effectively contribute to the increase in contraceptive options when introduced to family planning programs in Brazil.

Brazil↗

Latin american experience with two low-dose oral contraceptives containing 30 microg ethinylestradiol/75 microg gestodene and 20 microg ethinylestradiol/150 microg desogestrel.

The objective of this study was to compare cycle control, efficacy and tolerance of an oral contraceptive containing 20 microg ethinylestradiol and 150 microg desogestrel with a preparation containing 30 microg ethinylestradiol combined with 75 microg gestodene. This study involved 342 women and 4104 cycles use in Argentina, Brazil, Chile, and Mexico. Contraceptive efficacy was good with both formulations. Two pregnancies occurred in the desogestrel group but were not due to method failure. With respect to cycle control, the incidence of intermenstrual bleeding was higher during the first 3 cycles in the desogestrel group; it was significant (p <0.01) during the first 3 days of the cycle for a normal or heavy bleeding only in the Mexican group. Amenorrhea was not reported for any group, but the incidence of dysmenorrhea was significantly higher (p <0.01) in the Brazilian desogestrel group (13.8%) and was significantly lower (p <0.01) in the Mexican gestodene group (8.5%). Adverse events were similar in all the countries with headache, breast tension, and nausea, the most frequently reported symptoms. The range of mean increase in body weight varied from 0.2 kg in the Argentine group to 2.6 kg in the Chilean group (95% confidence limit, +/- 2.51) in the gestodene group, and 0.2 kg in the Argentine group to 2.5 kg in Brazilian group (95% confidence limit, +/- 2.36) in the desogestrel group. Fifteen women discontinued because of headache, but there were no significant differences between the groups regarding discontinuation for this and other medical or non-medical reasons. Both oral contraceptive preparations are reliable and well tolerated, and both have favorable effects on control cycle.

Adolescent↗

T-shaped IUDs accommodate in their position during the first 3 months after insertion.

The objective of this study was to observe the position dynamics of the T-shaped intrauterine device (IUD) in the uterine cavity, from insertion to 90 days of use. IUD position was evaluated in 214 women by vaginal ultrasound, measuring the IUD-endometrium, IUD-myometrium, and IUD-fundus distances. The 90th percentile of the IUD-endometrium distance was 5, 6, and 8 mm at time of insertion, 30 and 90 days of use; 7, 9, and 10 mm for IUD-myometrium distance; and 23, 24, and 27 mm for IUD-fundus distance, respectively. Seventeen IUDs were classified as misplaced at insertion by using the 90th percentile of the IUD-myometrium distance as standard. Of these, only 6 remained misplaced after 90 days of use. On the other hand, 21 IUDs were beyond the 90th percentile at the 90-day observation, only 6 of which were considered misplaced at insertion. We conclude that the T-shaped IUD accommodates its position in the uterine cavity during the first 3 months following insertion, and that ultrasound evaluation of its position is not a good predictor of future evaluation.

Adult↗

Forearm bone density in users of Depo-Provera as a contraceptive method.

OBJECTIVE: To determine the influence of depot medroxyprogesterone acetate (MPA) on bone mineral density when used as a contraceptive method. DESIGN: Cross-sectional study. SETTING: Academic tertiary-care hospital. PATIENT(S): Fifty premenopausal women who had used depot MPA as a contraceptive method for > or =1 year and 50 women who had never used hormonal contraceptive methods. INTERVENTION(S): Bone mineral density was evaluated at the midshaft and at the distal radius of the nondominant forearm using single x-ray absorptiometry. MAIN OUTCOME MEASURE(S): Bone mineral density. RESULT(S): Bone mineral density at the midshaft of the forearm was lower in depot MPA users than in women who had never used hormonal contraceptive methods, but the difference was not statistically significant. At the distal portion, bone mineral density was significantly lower in the study group. The duration of depot MPA use was not related to bone mineral density. CONCLUSION(S): Women > or =35 years of age presented with a lower bone mineral density only at the distal portion of the forearm after the use of depot MPA for > or =1 year. However, this decrease was not related to the duration of depot MPA use. It is not possible to conclude that women who use depot MPA are at risk of osteoporosis.

Adult↗

Endometrial histology in long-term users of the once-a-month injectable contraceptive Cyclofem.

This study evaluated endometrial histology in women using the once-a-month injectable contraceptive Cyclofem for one year or more. The study received IRB approval. Seventeen Cyclofem users accepted to be submitted to an endometrial biopsy. All the samples were collected with an endometrial suction curette (Z-Sampler, ZSI Gynecological Product, Chasworth, CA, USA) in an outpatient clinic, 27-33 days after the last injection. The material was fixed immediately in Bouin solution prior to wax embedding and screened as a routine histological examination by a senior pathologist. The pathologist did not know the bleeding status of each woman or the number of injections each woman had received before the biopsy. All women recorded bleeding and spotting for the last 60 days prior to the biopsy. The mean age of volunteers was 25.9 years (range 21-32) and the mean number of injections received was 24.8 (range 14-47). The results were: 4 out of 17 biopsies were found to be inadequate for diagnosis because they consisted of only blood and mucus. Two of these women were bleeding regularly and the other 2 had amenorrhea. Eight endometrial samples presented a proliferative pattern and, in this group, 3 women had amenorrhea and 5 were bleeding regularly. The other 5 biopsies were reported as secretory endometrium, and 4 of them showed pseudodecidual reaction compatible with the administration of progestin. All of these women were bleeding regularly. The results of the biopsies were not related to the number of injections received nor to the age of the women. In conclusion, long-term administration of the injectable contraceptive Cyclofem did not produce adverse alterations in the endometrium as hyperplasia.

Adult↗

Comparison of the performances of TCu380A and TCu380S IUDs up to five years.

A modification of the TCu380A IUD to create the model TCu380S was introduced many years ago. The TCu380S utilizes copper sleeves that are flush in the plastic and are set at both ends of the horizontal arm. The objective of this study is to compare the clinical performance of the TCu380A and the TCu380S IUDs, especially regarding contraceptive performance and expulsion, in a cohort of women who had one of these two devices inserted at random. This paper presents the results up to 5 years of use. A total of 1568 women were enrolled: 806 women received a TCu380A and 762 women received a TCu380S IUD. The performance was evaluated by life-table analysis and significance between rates was tested by the method of log-rank. The cumulative pregnancy rate was low in users of both models of IUD but lower in users of the TCu380S model through the 5 years of use, without statistical significance. Expulsion was significantly higher in users of the TCu380S model during the five years of use. The other reasons for discontinuation were similar for both devices and did not show statistical significance. The continuation rate was significantly lower in users of the TCu380S model in the first and second years of use. Both devices presented a very low pregnancy rate and TCu380S presented a lower pregnancy rate than the TCu380A, although without statistical significance.

Adolescent↗

T-shaped IUD move vertically with endometrial growth and involution during the menstrual cycle.

Ultrasound has been used to detect and evaluate intrauterine device (IUD) position for some years. Different definitions of the IUD in the uterine cavity have been discussed trying to relate them to bleeding and pain complaints. Most of these definitions do not take into account the uterine wall or endometrial thickness. This is a secondary analysis of a previous cross-sectional study, in which 481 IUD users had their T-shaped IUD evaluated by transvaginal sonography. The correlation between the endometrium thickness and the IUD-myometral distance was studied, defined by the linear measurement between the upper end of the IUD and the myometrium/endometrium interface. These two measurements were highly correlated over the entire sample range (r = 0.29) and an even stronger correlation existed (r = 0.66) when only cases below the 90 percentile of the IUD-endometrial distance distribution were considered. These results suggest that the IUD position in the uterine cavity is influenced by the growth and thinning of the endometrium, and that this information should be considered when evaluating the IUD position by sonography.

Endometrium↗

Timing of onset of contraceptive effectiveness in Depo-Provera users: Part I. Changes in cervical mucus.

OBJECTIVE: To evaluate the changes in cervical mucus within the first hours or days after depot medroxyprogesterone acetate (MPA) injection so as to estimate the time at which cervical mucus becomes hostile enough to prevent pregnancy. DESIGN: Multicenter, clinical descriptive study. SETTING: Family planning clinic. PATIENT(S): Thirty women who were between days 8 and 13 of their menstrual cycle and who had requested Depo-Provera were enrolled in the study. INTERVENTION(S): Cervical mucus and blood samples were obtained; transvaginal ultrasonography was performed. MAIN OUTCOME MEASURE(S): Cervical mucus scores, sperm penetration distances, ovarian follicular size, and serum levels of progesterone and estradiol. RESULT(S): From 6 to 24 hours after injection, there was a sharp decline in the cervical mucus score for most of the subjects. All subjects exhibited poor mucus on day 3 after injection, and by day 7, all subjects had zero scores, with the exception of two outliers on each day. Sperm penetration, as measured by the vanguard sperm distance, was already poor (< 1 cm) in 7 of the 30 subjects at the time of injection and was reduced progressively up to 24 hours after injection, when only four subjects had a sperm penetration of > 1 cm. A rapid decline in the estimated number of sperm was observed at 12 hours and more so at 24 hours in the majority of subjects. CONCLUSION(S): The data presented in this report confirmed that depot MPA causes profound changes in cervical mucus after injection. Although very little change was seen at 6 hours, alterations were observed subsequently, with 90% of the subjects showing a poor cervical mucus score 24 hours after administration of the progestin. No reliable clinical marker is available to identify in which women depot MPA might exert its effect on cervical mucus within 3 days. Thus, we believe that at present, women should be informed of this uncertainty and should use a backup method of contraception for 7 days when the first injection of depot MPA is provided after the seventh day of the menstrual cycle.

Adult↗

Timing of onset of contraceptive effectiveness in Depo-Provera users. II. Effects on ovarian function.

OBJECTIVE: To determine the timing of onset of contraceptive effectiveness after the first injection of 150 mg of depot medroxyprogesterone acetate (DMPA) administered between days 8 and 13 of the menstrual cycle. DESIGN: Descriptive, prospective study. SETTING: A tertiary university referral center. PATIENT(S): Thirty healthy women between 18 and 40 years of age. INTERVENTION: Volunteers were injected with DMPA between days 8 and 13 (5 women on each day) of the menstrual cycle. MAIN OUTCOME MEASURE(S): Ovarian function determined by serum levels of E2 and progesterone and follicular development evaluated by vaginal ultrasound. RESULT(S): In nine (30%) of 30 women studied, DMPA did not prevent ovulation. All ovulations occurred in women receiving DMPA between days 10 and 13 of the cycle. No woman who received injections on day 8 or 9 ovulated. Ovulation suppression was more effective in women with low ovarian activity. All ovulation occurred within 3 days after the injection. CONCLUSION: A back-up contraceptive method, used after the 7th day of the menstrual cycle, is recommended for up to 7 days after the first injection of DMPA.

Adolescent↗

Weight variation in users of the once-a-month injectable contraceptive Cyclofem.

This study was aimed to evaluate weight variation in 3183 women using the injectable contraceptive Cyclofem. All women were allocated to groups according to their weight at admission. The weight gain was inversely proportional to the weight at admission. The groups of women weighing less than 50 kg at admission, experienced a higher increase, 2.8% in four months, and they continued gaining weight, reaching 7.7% in 13 months. Women weighing more than 64 kg at admission did not present any weight change in 4 months and increased only 1.7% at 13 months. When women were classifed as discontinuers due to weight increase, discontinuers due to other reasons, and continuers, at four months, the differences in the mean weight between the groups was statistically significant only in the groups weighing 55 kg or more at admission. At 13 months, the results were similar and the differences were statistically significant only in the groups weighing 55-59 kg and 60-64 kg. Discontinuation rates due to weight increase were proportional to the weight at admission. This rate was almost three times higher in the group of women weighing more than 64 kg at admission than in the group weighing less than 55 kg (p<0.001). In conclusion, considering the data presented in this study, it is impossible to recommend health providers to inform women who choose Cyclofem as their contraceptive method, that this method may increase their weight throughout its use.

Adult↗