Determination of patulin by reversed-phase high-performance liquid chromatography with extraction by diphasic dialysis

A simple and economical method has been developed for the determination of patulin in apple juice. The sample is extracted with ethyl acetate in a diphasic dialysis system, and the extract is cleaned up by elution from a Sep-Pak cartridge. Patulin is detected and determined by reversed-phase high-performance liquid chromatography using a Novapak C18 column and an ultraviolet detector. The lower detection limit is 1 microgram l-1 and the recovery is 85% at the 20 micrograms l-1 level.

Relative contributions of anovulation and luteal phase defect to the reduced pregnancy rate of breastfeeding women

OBJECTIVE

To evaluate the contribution of anovulation and luteal phase defects to lactational infertility.

DESIGN

Prospective longitudinal follow-up.

SETTING

Outpatient clinic.

SUBJECTS

Forty-nine women fully nursing and amenorrheic on day 75 postpartum and 25 cycling, interval non-nursing women.

INTERVENTIONS

Plasma prolactin, luteinizing hormone, estradiol (E2), and progesterone (P) levels twice a week up to the second postpartum menses.

MAIN OUTCOME MEASURES

Ovulation rate and endocrine profile of the menstrual cycles.

RESULTS

Ovulation rates were 37% and 97% at 6 and 12 months postpartum; 67% of ovulations occurred in amenorrhea. The luteal phase was shorter, and E2 and P levels were lower in lactating women than in non-nursing women. These parameters were closer to normal in the second cycle than the first, in spite of active nursing. The risk of ovulation and pregnancy in amenorrhea was 27.7% and 0.9% at month 6 postpartum. After the first menses, these risks were 93% and 7%, respectively.

CONCLUSION

The abnormal endocrine profile of the first luteal phase offers effective protection to women who ovulate during lactational amenorrhea within the first 6 months after delivery. Later luteal phases are improved and women are at risk of pregnancy.

Alterations in the cell wall of Saccharomyces cerevisiae induced by the alpha sex factor or a mutation in the cell cycle

We performed experiments in parallel to study the rate of synthesis of cell wall polysaccharides and the activity of glycosyl transferases in Saccharomyces cerevisiae after arrest of a cdc 28 mutant in G1 phase by either addition of alpha-factor or transfer to the non-permissive temperature. Both effectors brought about similar time-dependent increases in the rate of synthesis and deposition of the cell wall polysaccharides chitin, glucan and mannan. These changes in cell wall composition were accompanied by an increase in the specific activities of glucan and chitin synthetases. This increase was inhibited by cycloheximide suggesting that it represented de novo enzyme biosynthesis and not enzyme activation. Our data are consistent with the notion that both alpha-factor and the cdc 28 mutation affect the same stage-specific function that controls the temporal expression of glycosyl transferases.

Clinical trial with 3-keto-desogestrel subdermal implants

The study was done to assess the clinical performance and in vivo steroid release rate of 3-keto-desogestrel subdermal implants designed to deliver 5 different doses of the progestin. Volunteers were healthy women of proven fertility who provided blood samples at scheduled intervals during treatment. No pregnancy occurred in 514 woman-months in users of implants delivering 30 and 40 micrograms per day of 3-keto-desogestrel. Three pregnancies, one ectopic, were observed in 109 woman-months recorded with implants delivering 20 micrograms per day or less. Ovulation was inhibited, as judged by depressed progesterone levels, in 57 of 59 (97%) blood samplings in women whose 3-keto-desogestrel plasma levels were greater than 0.28 nmol/L and in 39 of 75 (52%) of cases with lower levels. Users of 4 cm implants manufactured by The Population Council, New York, showed mean levels above 0.28 nmol/L until 18 months of use. Levels achieved with 4.4 cm implants manufactured by Organon, Oss, Holland, were less consistent. No changes were observed in the plasma lipoprotein pattern or clinical chemistry during treatment. The main complaint was the occurrence of bleeding irregularities, particularly with the lower doses. Ovarian cysts found during pelvic examination in 11 (22%) subjects disappeared spontaneously within 7-90 days. 3-keto-desogestrel implants releasing around 40 ug/day and providing plasma levels around 0.28 nmol/L afford efficient contraceptive protection.

Mechanism of action of progesterone as contraceptive for lactating women

Progesterone vaginal rings releasing 5-15 mg/day were tested as a contraceptive for lactating women. Progesterone plasma levels achieved ranged from 10 to 20 nmol/L. Pregnancy rates at the end of the year were less than 1% and 39% in treated (n = 210) and untreated (n = 236) nursing women, respectively. Around 70% of treated and 30% of untreated women were amenorrheic at 8 months post partum. The endocrine profile during the first 8 months post partum was assessed in 36 treated and 28 untreated nursing women. Pre- and postsuckling prolactin (PRL) levels were measured at 1600 hr at fortnightly intervals and E2 determinations and ovarian ultrasound were performed twice a week. Prolactin increases in response to suckling and postsuckling PRL levels were higher, E2 levels were lower, and follicular growth was arrested at earlier stages in progesterone-treated than in untreated women. The pattern observed in progesterone-treated women was similar to that in prolonged lactational amenorrhea. This suggests that progesterone increases the sensitivity of the breast-hypothalamic-pituitary system to suckling and reinforces the mechanism of lactational infertility.

Contraceptive efficacy of lactational amenorrhea in urban Chilean women

The contraceptive efficacy of breastfeeding was assessed in 236 healthy urban women who were followed at monthly intervals during the first postpartum year. Proportional hazard models were used to evaluate the influence of time postpartum, menstrual status and breastfeeding pattern upon the risk of pregnancy. Time and menstrual status had a highly significant effect on this risk. Those women who remained in amenorrhea had cumulative probabilities of pregnancy of 0.9% and 17% at 6 and 12 months postpartum, respectively. In those who recovered menstrual cycles, the risk rose to 36% and 55% at 6 and 12 months, respectively. Milk supplementation also increased significantly the risk when considered alone but not when time and/or menstrual status were included in the analysis. However, amenorrheic women who introduced bottle feeding, had a higher risk of pregnancy after 6 months postpartum than those who remained fully nursing. The analysis was unable to detect a significant influence of the nursing frequency. The results confirm that lactational amenorrhea is an effective contraceptive during the first six months postpartum. The first postpartum bleeding marks a great increase in the risk of pregnancy. Supplementation also increases the risk, particularly in amenorrheic women.

Early difference in the endocrine profile of long and short lactational amenorrhea

The endocrine profiles associated with long and short lactational amenorrhea were assessed in a longitudinal study in which morning blood samples were drawn in 48 women from the first postpartum month until the recovery of ovulation and in a cross-sectional study in which the samples were drawn throughout 24 h at the end of the third postpartum month in 10 fully nursing and amenorrheic women. PRL, LH, FSH, estradiol (E2), progesterone, cortisol, and dehydroepiandrosterone sulfate were measured. In both studies we detected a smaller PRL increase in response to suckling (P less than 0.001) and higher E2 levels (P less than 0.001) in nursing women who ovulated within 6 months postpartum compared to those in women who did not. Such differences were observed early after delivery when all women were fully nursing and amenorrheic. These results suggest some probable sources of variability in the duration of lactational amenorrhea in our population. The greater PRL response to suckling associated with longer amenorrhea may be due to higher sensitivity of the breast-hypothalamus-pituitary system or a stronger suckling stimulus in this group. Differences in plasma E2 levels between longer and shorter periods of amenorrhea may reflect dissimilar endogenous production, intake, or clearance of estrogens.

Clinical assessment of treatments for prolonged bleeding in users of Norplant implants

The effectiveness of three drugs in controlling prolonged bleeding in the first year of NORPLANT implants use was tested. The drugs were levonorgestrel (L-Ng, 0.03 mg twice a day for 20 days), ethinylestradiol (EE, 0.05 mg per day for 20 days) and ibuprofen (Ib, 800 mg three times a day for 5 days) and were given orally. A control group received a placebo (PL, one pill of lactose for 20 days). Treatment should start each time a woman experienced eight consecutive days of bleeding or spotting. The 183 volunteers were not aware of the drug administered. A daily record of bleeding and spotting and of treatment intake was maintained. One-hundred-forty women completed the study period; 60 never used the prescribed treatment. Women treated with the three test drugs had significantly fewer bleeding and spotting days during the treated month and also throughout the study year than women using the placebo. The mean number of bleeding plus spotting days per actually treated subject in the first year was 77, 94, 101 and 129 days for the EE, Ib, L-Ng and PL groups, respectively. The administration of EE might help in the management of prolonged bleeding during the first year of NORPLANT implants use.

A longitudinal study on cortisol, prolactin and thyroid hormones in users of Norplant subdermal implants or a copper T device

A longitudinal study was undertaken to assess PRL, cortisol, TSH, T3 and T4 levels in NORPLANT implant users (n = 22) and Copper T users (n = 20). Participants were healthy women with no contraindication for hormonal contraception. Samples were drawn at 0930 to 1000 h twice pretreatment and at month 2, 4, 6, 12, 24 and 36 after insertion. At the second treatment month, a second sample was obtained at 1600 h to assess cortisol diurnal variation. Hormones were measured by RIA. Values for all hormones were similar in Norplant and Copper T users. No significant changes occurred throughout the study period. Elevated PRL levels (greater than 500 mU/1) were found in three women from each group before and during treatment but no clinical evidence of hyperprolactinemia was detected. The results of this study reassure that long-term use of NORPLANT implants do not impair plasma levels of cortisol, prolactin and thyroid hormones.

Circadian variation of basal plasma prolactin, prolactin response to suckling, and length of amenorrhea in nursing women

The circadian pattern of plasma PRL levels and the PRL response to suckling were examined at various times during the first postpartum year and related to the length of lactational amenorrhea. Ten healthy women whose infants were breast-fed exclusively and who were amenorrheic 3 months postpartum were studied 3, 6, and 9-11 months postpartum. The women and their babies were admitted to a metabolic unit for 48 h. On the second day, blood samples were drawn at 2-h intervals for 26 h starting at 0800 h and also 10 and 30 min after the initiation of six of the nursing episodes. During the three postpartum periods, there was a circadian rhythm of basal plasma PRL concentrations; the peak concentrations occurred between 2400-0600 h. Suckling induced a significant rise in plasma PRL levels at all hours except 0800 h. There was a positive correlation between the duration of the nursing episode and the suckling-induced PRL increase at 30 min. Both the basal plasma PRL levels and the PRL responses to suckling diminished with time after delivery. This trend was less evident at 0400 h and was not fully explained by changes in the nursing pattern. The five women in whom menstrual cycles resumed before day 180 postpartum had lower basal and suckling-induced plasma PRL levels than the women who had amenorrhea for a longer period. This difference was present in the third month, when all women were amenorrheic and fully nursing and when the frequency and duration of nursing episodes and infant growth rates were similar. The results indicate that comparable nursing patterns may be associated with different plasma PRL levels, which are associated with different lengths of lactational amenorrhea. An early difference in the sensitivity of the breast-hypothalamus-pituitary system to suckling may explain the differences in the duration of lactational amenorrhea, which are not dependant on the breastfeeding pattern. The magnitude of the PRL response to suckling may predict the likelihood of recovering ovarian function during lactation.

Clearance of levonorgestrel from the circulation following removal of NORPLANT subdermal implants

The disappearance of levonorgestrel from plasma after the removal of NORPLANT subdermal implants was studied in 12 women who had been treated from 5.5 to 78 months. The existence of one or two half-lives for the rate of disappearance was assessed. The influence of body weight, body fat and length of treatment upon levonorgestrel clearance was studied through stepwise regression analysis. It was found that the levonorgestrel decay rate after implant removal can be entirely accounted assuming one half-life of 42 +/- 16 h (mean +/- SD; range 13 to 62 h). Stepwise regression analysis showed that levonorgestrel half-life is positively correlated with body weight and not significantly correlated with the length of treatment or body fat. It is concluded that, after long-term administration of levonorgestrel via subdermal implants, the major part of the steroid is cleared from plasma within 96 h and that only trace amounts are detected in the following days.

Estradiol plasma levels during long-term treatment with Norplant subdermal implants

Estradiol-(E2) plasma levels were assessed in forty-seven women treated for one through seven years with the same set of Norplant implants. Each woman was subjected to one (n = 34), two (n = 11) or three (n = 2) sampling runs. At each sampling run, blood samples were drawn every third or fourth day during 5 or 6 consecutive weeks. Sampling runs were classified as ovulatory (n = 11), anovulatory (n = 49) or uncertain (n = 1) according to progesterone levels. Controls were Copper T users (n = 8), all classified as ovulatory. No significant differences were found for the mean E2 levels between Norplant users and Copper T users and between ovulatory and anovulatory cases. The mean of the peak E2 value found in each sampling run was significantly higher in anovulatory Norplant subjects than in the control group. The mean of the minimum E2 level observed was significantly lower in Norplant cases than in Copper T users. A single woman from the Norplant group and none from the Copper T group had all E2 values below 370 pmol/l. The inhibition of the reproductive function induced by Norplant implants is associated with a wider range of E2 circulating levels. None of the values observed at the extremes should cause serious concerns. High peaks are transitory and opposed by the antiestrogenic effect of levonorgestrel. Persistent low levels which could be associated with a hypoestrogenic state were observed in a single case.

Lactational amenorrhea and the recovery of ovulation and fertility in fully nursing Chilean women

The probability of experiencing the first postpartum bleeding, the first ovulation and the risk of pregnancy during exclusive breastfeeding was assessed in a selected group of urban Chilean women. Admission criteria included having had a normal pregnancy and a vaginal term delivery of a healthy infant and the desire to maintain breastfeeding for as long as possible. The risk of bleeding and the recovery of ovulation was assessed in 48 women selected for being amenorrheic and fully nursing at day 75 postpartum and their willingness to participate in the blood sampling protocol. The first bleeding and ovulation was experienced while fully nursing by 28% and 26% of these subjects, respectively, at day 180 postpartum. The probability of experiencing the first bleeding and the probability of pregnancy during full nursing were calculated for 236 women not contracepting who were enrolled during the first month postpartum. The cumulative probability of bleeding and of pregnancy was 52% and 9.4% at day 180 postpartum, respectively. The risk of pregnancy was less than 2% in the subset of amenorrheic cases. In this urban population selected for having the highest motivation and best breastfeeding performance, the association of breastfeeding with infertility was too weak to serve as an effective birth spacer, except for the period of lactational amenorrhea. When the first postpartum bleeding took place before the sixth postpartum month in fully nursing women, it had a good predictive value to indicate the onset of a higher risk period.

Breastfeeding pattern and the duration of lactational amenorrhea in urban Chilean women

The influence of the breastfeeding pattern and several clinical variables upon the duration of postpartum amenorrhea was assessed in a group of healthy women selected for having had a normal pregnancy and delivery and being highly motivated for prolonged breastfeeding on demand. 676 women who were fully nursing at the second month postpartum entered the study. Supplements were administered to 11% and 48% of the infants by the end of the 3rd and 6th month, respectively. The first bleeding was experienced before the end of the sixth month postpartum by 57% of the cases. Supplementation had a strong negative influence while nursing frequency had a significant positive influence upon the length of amenorrhea. Notwithstanding, a frequency of 8+ suckling episodes per 24 h could not maintain amenorrhea in around half of the subjects. Age and parity had a moderate negative influence upon the risk of experiencing the first postpartum bleeding. Maternal weight and ponderal index, infant sex, birth weight and growth rate showed no significant influence upon the length of amenorrhea. In this urban population selected for having the highest motivation and best breastfeeding performance, the association of breastfeeding with amenorrhea was weak in comparison with what has been described for other populations. The risk of experiencing the first bleeding was reduced while fully breastfeeding with a high number of nursing episodes per day and night, particularly in older women with higher parity. But even in such situation 25% and 50% of the women had started to cycle by the end of the fifth and eight postpartum month.

A study on the feasibility of suppressing ovarian activity following the end of postpartum amenorrhoea by increasing the frequency of suckling

The aim of the study was to test the effect of increasing the frequency of breastfeeding upon ovarian function following the end of postpartum amenorrhoea. Women exclusively breastfeeding (n = 14) who experienced their first postpartum menstruation between the third and fifth month after delivery were randomly allocated to an experimental (n = 7) and a control (n = 7) group and studied during the next two cycles. Women in the experimental group agreed to increase the number of breastfeeding episodes per day throughout the second cycle. Blood samples were drawn twice a week from the first to the third postpartum menstruation for prolactin, oestradiol and progesterone determinations. The number of breastfeeding episodes per day and night and the length of each episode were recorded daily. An average frequency of 11 nursing episodes per 24 h was reported during the first study cycle in both groups. The experimental group increased by 50% the breastfeeding frequency after the second menstruation while the control group kept its spontaneous feeding pattern. The increase of suckling frequency occurred mainly during day hours. The total breastfeeding time per 24 h was not increased. The length of the menstrual cycle was not altered by the increased suckling frequency. The endocrine pattern differed neither between the first and second cycle of the experimental group nor between the experimental and control group, with the exception of PRL levels which were higher in the experimental group throughout both cycles. Twenty cycles (71%) showed progesterone values compatible with ovulation (greater than 9.5 nmol/l). The highest progesterone values and the highest oestradiol values observed in the ovulatory cycles of lactating women were within the range found in non-nursing fertile women. Plasma levels of PRL were significantly elevated in all cycles but one, in comparison with PRL levels in non-nursing women. It is concluded that if cyclic ovarian function is reestablished early in fully nursing women, a mere increase in the number of breastfeeding episodes, without augmenting total suckling time and the frequency of nocturnal episodes, does not provide a sufficient stimulus to resuppress the pituitary-ovarian axis.

Treatment with Norplant subdermal implants inhibits sperm penetration through cervical mucus in vitro

Attempts were made to collect several samples of cervical mucus in each of thirty-three cycles of women using NORPLANT subdermal implants, in seven cycles from NORPLANT-2 rod users, and in 33 control cycles. The attempts to collect a mucus sample were successful on 20 of 77 and 7 of 14 occasions in NORPLANT capsule and rod users, respectively, due to the scanty amount and stickiness found in the majority. All 59 attempts in control subjects were successful. The distance travelled by the fastest sperm and by the bulk of spermatozoa through the cervical mucus in vitro was assessed after 10 min of incubation with a normal semen sample. The best score for each cycle was considered for the comparison between treated and control cases. Sperm penetration was greatly impaired in mucus samples of implant users with penetration by the fastest sperm exceeding 10 mm in only two instances and exceeding 20 mm in none. In 30 of 33 control samples, the fastest sperm travelled 21 mm or more and in 28, the bulk of spermatozoa travelled further than 10 mm. Unsuccessful attempts to collect mucus and poor sperm migration were observed in NORPLANT implant users even when circulating estradiol levels were comparable to those seen in the late follicular phase of the normal menstrual cycle. These results suggest that the principal mechanism by which NORPLANT implants prevent pregnancy is by interference of sperm migration through cervical mucus.

Recovery of fertility and outcome of planned pregnancies after the removal of Norplant subdermal implants or Copper-T IUDs

The recovery of fertility after discontinuation of NORPLANT implant use was assessed in ninety women who stated a desire for a new child at the time of removal. Three subjects were lost to follow-up after removal. The cumulative probability of conception in the remaining 87 women was 25, 49, 73 and 86 percent at one, three, six and twelve months after removal, respectively. Nine observations were censored either because of the use of a contraceptive method soon after removal of the implants (n = 7) or separation (n = 2). All other cases were pregnant at the end of two years with exception of three subjects where a male factor for infertility was present. There was no significant correlation between the length of NORPLANT use and the length of the interval from removal to conception. A significantly higher frequency of intervals longer than 6 months was observed among women older than 30 years as compared to younger women. Pathology during pregnancy was cholestasia (n = 5), hypertension (n = 1) and gestational diabetes (n = 1). The outcome was term delivery in 59 cases, premature delivery in 4 cases, and spontaneous abortion in 7 cases. One woman is still pregnant and the outcome is unknown in 4 cases. One premature infant died. A contemporary control group of Copper T users enrolled under the same criteria as NORPLANT implant users provided 44 women who had the device removed to become pregnant. The cumulative probability of pregnancy was 27, 69, 84 and 89 at one, three, six and twelve months and all were pregnant by the end of the second year. Six censored observations occurred because of the use of another contraceptive method after removal (n = 3) or loss to follow-up (n = 3). The outcome of pregnancy was term delivery in 23 cases and abortion in 7 cases. Recovery of fertility occurred at a normal rate after NORPLANT implant removal and the incidence of problems detected in the ensuing pregnancy were within the expected range for Chilean women.

Long-term follow-up of women treated with Norplant implants

This report describes the long-term follow-up of 376 women who received NORPLANT implants in the period October 1974 through May 1979. One-hundred-and-ten subjects received replacement implants after variable lengths of use of the first set. The average levonorgestrel plasma levels declined steadily through eight years of use of NORPLANT capsules (r = -.937). Values were 0.35 ng/ml, 0.29 ng/ml and 0.22 ng/ml at treatment years 1, 5 and 8, respectively. Levonorgestrel plasma levels after replacement with a second set of implants were similar to those observed after the first insertion, either when placed in the same site as the first set or in a different area. Nineteen pregnancies occurred during 18,530 woman-months of use of the first set of implants, eleven of them during years 6 through 8 of treatment. The Pearl Index for the first 5 years of NORPLANT implants use was 0.63. No pregnancy has occurred in 4194 woman-months observed during treatment with a second set of capsules. Fifty-six women (14.9%) out of 376 acceptors of the first implant and 10 (9.1%) out of 110 acceptors of the replacement implants were terminated for other medical reasons, mainly bleeding problems and side effects commonly associated with hormonal contraception. Two women died while using NORPLANT implants, one of a cardiac arrest after surgery for a gallbladder disease and one because of endocranial hypertension originating from the rupture of an aneurism of the median cerebral artery. The bleeding pattern observed in the three months after NORPLANT capsules replacement was similar to that observed in the 90 days before replacement and different from that experienced by the same women in the first 90 days of implant use. This finding can be interpreted as an indicator of adaptive changes experienced by the target organs during long-term continuous administration of levonorgestrel. The prompt recovery of fertility after removal of NORPLANT implants suggests that these changes are reversible.

The place of progesterone in human contraception

Progesterone, the natural hormone produced by the corpus luteum and other steroid-secreting glands, is endowed with antiestrogenic action and has a fundamental role in the initiation and maintenance of pregnancy and in the regulation of gonadotropin secretion. Although it was discovered half a century ago, it has found little clinical use as a therapeutic agent due to its low potency and extensive degradation following oral administration in comparison with a variety of highly potent synthetic analogs that became available in the last three decades. When delivered systemically, a large proportion of the dose bypasses degradation in the gut and liver, and progesterone can achieve effective levels in target tissues for clinical use. Sustained administration via compressed pellets implanted subdermally or silicone rubber rings placed in the vagina produced circulating levels of progesterone within the lower third of those found in the luteal phase of the human menstrual cycle. Those levels were shown to delay the recovery of fertility in nursing women without adverse effects to the mother or the infant. Progesterone transferred to the babies via the breast milk did not change their rate of pregnandiol-3-alpha glucuronide excretion. It is concluded that sustained administration of the natural hormone progesterone may be an effective and safe contraceptive method for nursing women.

Bleeding pattern, outcome of accidental pregnancies and levonorgestrel plasma levels associated with method failure in Norplant implants users

The aim of this study was to characterize the bleeding pattern, the outcome of pregnancies and the levonorgestrel plasma levels associated with method failures in Norplant implants users. Nineteen pregnancies are reported in 458 woman and 21,589 woman-months observed during the first eight years of Norplant use. Pregnancy rates increased slightly during the first six years of use, attaining a Pearl Index above three thereafter. All women who became pregnant had experienced a regular bleeding pattern in the six months preceding conception. Levonorgestrel plasma levels observed at different intervals before conception and during the conceptional cycle were similar to those observed in non-pregnant women at comparable intervals after Norplant insertion. The nineteen pregnancies ended in thirteen term deliveries, one premature delivery, three abortions and two ectopic pregnancies. No abnormalities were found in the infants. The two ectopic pregnancies are the only ones reported for Norplant users in The Population Council studies. The overall incidence is less than 0.8 per 1000 woman-years.

Fertility regulation in nursing women: VIII. Progesterone plasma levels and contraceptive efficacy of a progesterone-releasing vaginal ring

The objectives of this trial were to test the contraceptive efficacy and measure progesterone plasma levels of women using progesterone-releasing rings during lactation. Two types of rings delivering an average of about 5 mg or 10 mg of progesterone per day were tested in 128 healthy nursing women. A control group was formed by 127 Copper T users. Rings were inserted at day 60 postpartum and replaced every 3 months with a new one. Initially progesterone plasma levels were around 10 nmol/l and 15 nmol/l for rings releasing 5 and 10 mg per day, respectively, and decreased slightly after 30 days. Levels observed in subsequent segments of use approximated those of the first segment. These levels are within the range shown to inhibit fertility in lactating women. One pregnancy was diagnosed in 739 woman-months of progesterone ring use, and none occurred in 794 woman-months of Copper T use, which contrasts with the high incidence of pregnancy in a group of untreated nursing women where 19 pregnancies resulted during 677 woman-months. No deleterious effects were detected lactation and infant growth or maternal and infant health. It is concluded that the vaginal rings releasing progesterone are a suitable contraceptive method for lactating women.

Fertility regulation in nursing women: VII. Influence of NORPLANT levonorgestrel implants upon lactation and infant growth

The objective of this study was to test the influence of NORPLANT implants upon lactation and infant growth. The results obtained during the first postpartum year are reported. One-hundred women were enrolled in the implant group. The control group was formed by 100 women who received a Copper T IUD. Treatments were administered at day 55 +/- 3. At admission all subjects were in exclusive breastfeeding with an adequate weight increase of the infant. No significant differences were found between the treated and control groups in the percentage of women in full nursing at different postpartum intervals, except for the 12th month postpartum where a lower percentage of cases from the NORPLANT group was in the full nursing category. No difference was found in the time of weaning. The infants showed a normal weight gain rate in both groups although the girls from the NORPLANT group showed a significantly lower daily weight increase during the 4th month than the girls from the IUD group. No pregnancies were diagnosed. No women asked for implant removal during the first year. No serious side effects related to treatment were detected. Bleeding irregularities were rare during breastfeeding which is in contrast with what occurs in non-nursing women treated with NORPLANT implants. Levonorgestrel concentrations found in milk were variable and individual values ranged from 23 to 311 pg/ml. The dose received by the infant can be estimated around 15 to 18 ng/Kg/day during the first month of treatment when the higher plasma values of levonorgestrel are observed. These levels is conjunction with the clinical observations reported here minimize the potential problems associated with levonorgestrel transference through maternal milk. Nevertheless, long-term studies are required to settle this matter and until more information is available, NORPLANT implant use in lactating women should be limited to cases who require a highly effective contraceptive method and where non-hormonal methods of similar effectiveness are contraindicated or unacceptable.

Plasma levonorgestrel and progesterone levels in women treated with silastic covered rods containing levonorgestrel

Levonorgestrel and progesterone plasma levels were measured in women bearing levonorgestrel subdermal implants. Two groups using four or six levonorgestrel covered rods and one group of non-hormonal contraceptors were compared. Blood samples were drawn twice a week for six consecutive weeks at different intervals after treatment administration. The mean levonorgestrel levels (mean +/- S.D.) observed in the four rods group was .49 +/- .13 ng/ml in the first year and decreased to .34 +/- .06 in the fifth year of treatment. The mean values observed in the six rods group were .70 +/- .15 ng/ml in the second year and .43 +/- .11 in the sixth year. The levonorgestrel plasma levels were slightly above those found with Norplantr implants in the four rods group and well above it in the six rod group. The highest plasma progesterone value found in each sampling period was above 9 nmol/l in 7 (14%) out of 50 subjects in the four rods group, in 2 (4.3%) out of 47 subjects in the six rods group and in all the 49 control women. In 4 out of the 7 subjects from the 4 rods group and in the two subjects from the 6 rods group, the highest progesterone value was preceded and followed by values lower than 6 nmol/l. It was concluded that the progesterone levels were seldom compatible with the occurrence of ovulation in women treated with four or six levonorgestrel covered rods which release an estimated daily dose of 70 and 105 micrograms, respectively.

Clinical chemistry in women treated with six levonorgestrel covered rods or with a copper IUD

A group of women treated with six levonorgestrel covered rods participated in a study on general chemistry and blood levels of selected hormones at treatment months 20 and 65. A comparable group of Copper T users served as control. Parameters analyzed were the SMA 12 chemistry profile, estradiol, testosterone, cortisol, T3, T4 and TSH. Samples from treated and control subjects were drawn within the same calendar period and were run simultaneously for the assay of each parameter. The values observed were within the normal limits. Significantly higher values of total protein and albumin and lower levels of estradiol and testosterone were found among implant users when compared to the control group. The results suggests little or no metabolic changes in users of six levonorgestrel covered rods which release a daily dose of approximately 105 micrograms.

Relationship between pathogenesis and immune regulation mechanisms in histoplasmosis: a hypothetical approach

The cellular immune response may be the principal mechanism of defense against infection with Histoplasma capsulatum. Subsequently, regulation of cell-mediated immunity could be fundamental to the outcome of disease. Suppressive phenomena-present in the host before infection or brought about by fungal components-would explain the various courses of infection. The fact that high titers of antibodies are associated with a poor cellular response suggests that antibodies may have a role as "regulatory molecules" in histoplasmosis. Antibodies may modulate the expression of the cellular response either by direct inhibition or by activation of the suppressor cell population, thereby interfering with the infectious process.

Fertility regulation in nursing women. VI. Contraceptive effectiveness of a subdermal progesterone implant

Six progesterone pellets implanted subdermally were tested as contraceptive method for lactating women. One pregnancy was diagnosed in 1614 woman-months of observation, a failure rate which was similar to that observed in a contemporary group of Copper T users. Nineteen pregnancies were diagnosed in the 677 woman-months observed in untreated lactating women. The progesterone implants were effective when administered either at 30, 60 or 240 days after delivery. The duration of the effective life was 5 months and fertility was quickly restored afterwards. There were no deleterious effects upon maternal or infant health or upon lactation and the rate of child growth. The main problem encountered was the occurrence of pellet expulsion at a variable rate which appeared related to the manufacturing procedure.

Growth pattern of selected urban Chilean infants during exclusive breast-feeding

This report describes the growth pattern of healthy, low middle and low socioeconomic class Chilean infants during exclusive breast-feeding. Two-hundred forty-two infants who were on exclusive breast-feeding at day 30 postpartum entered the study. Of these, 59% were fully nursing at 6 months and grew at a normal rate without receiving either supplementary milk or nondairy food. Supplementary feedings were administered in 27% of cases because of suspected primary inadequate milk output and in 14% of cases for other reasons such as pregnancy, illness, maternal work, or self-prescription. Full nursing provided the highest rate of weight increase during the first 3 months of life and a greater weight gain for boys than for girls up to the age of 6 months. Gastrointestinal pathology, malnourishment, or hospitalization were rare events in this population. It is concluded that maternal milk alone, if produced in sufficient amounts, can maintain normal growth up to the 6th month of life. The study supports the choice of exclusive breast-feeding on demand plus child growth monitoring up to 6 months over routine prescription of supplements at earlier times particularly where supplement administration fails to meet individual requirements.

Fertility regulation in nursing women: IV. Long-term influence of a low-dose combined oral contraceptive initiated at day 30 postpartum upon lactation and infant growth

The study was designed to test the long-term influence of a low-dose combined oral contraceptive upon lactation and infant growth when treatment was initiated at day 30 postpartum. The contraceptive tested contained ethinyl estradiol 0.03 mg and levonorgestrel 0.15 mg. Two control groups were formed by women who received an injectable placebo or a Copper T at day 30 postpartum. Women in the injectable placebo group received non-hormonal contraceptives at day 90 postpartum. An exacting list of requirements for admission and continuation in the study was applied to all groups. The oral contraceptive group had a significantly lower percentage of cases in full nursing from the 4th through the 10th postpartum month when compared to both control groups. The average absolute weight of infants in the oral contraceptive group was significantly lower at several ages when compared to the placebo group but not when compared to the Copper T group. No adverse side effects upon infant's health were detected. It was concluded that the oral contraceptive tested showed a moderate inhibitory influence upon lactation when treatment was initiated at the beginning of the second postpartum month.

Fertility regulation in nursing women: III. Short-term influence of a low-dose combined oral contraceptive upon lactation and infant growth

The study was designed to test the short-term influence of a low-dose combined oral contraceptive upon lactation and infant growth when treatment was initiated at day 30 postpartum. The contraceptive tested contained ethinyl estradiol 0.03 mg and levonorgestrel 0.15 mg. Two control groups were formed by women who received either an oral placebo or an injectable placebo at day 30 postpartum. An exacting list of requirements for admission and continuation in the study was applied to all groups. The oral contraceptive group had a lower percentage of cases in exclusive breastfeeding at day 91 postpartum when compared to both control groups. Infants in the oral contraceptive group showed a significantly lower average absolute weight at days 61 and 91 postpartum and a significantly lower average daily weight increase during the first month of treatment when compared to both control groups. It was concluded that the oral contraceptive tested had a negative influence upon lactation and child growth.

Fertility regulation in nursing women: V. Long-term influence of a low-dose combined oral contraceptive initiated at day 90 postpartum upon lactation and infant growth

The study was designed to test the long-term influence of a low-dose oral contraceptive upon lactation and infant growth when treatment was initiated at day 90 postpartum. The contraceptive tested contained ethinyl estradiol 0.03 mg and levonorgestrel 0.15 mg. The control group was formed by women who chose non-hormonal contraception at the same postpartum time. Only cases who were in exclusive breast-feeding with a minimal infant daily weight increase of 20 g per day during the third month of age were included. The oral contraceptive group showed a significantly lower percentage of cases in full nursing from the 6th postpartum month and a significantly lower infant weight increase during the 4th month of age when compared to the control group. No differences were found in the absolute infant weight up to one year of age. No adverse side effects upon infant's health were detected. It was concluded that the oral contraceptive tested showed a moderate inhibitory influence upon lactation when treatment was initiated at day 90 postpartum.

Fertility regulation in nursing women. II. Comparative performance of progesterone implants versus placebo and copper T

A clinical study was designed to test whether sustained administration of progesterone to nursing mothers could prolong lactation and delay the postpartum recovery of fertility. The hormone was administered by subdermal implantation of six pellets that each contained 100 mg of progesterone. This treatment was administered to 84 fully nursing women on day 30 post partum. Control groups were composed of 130 fully nursing women who received an injectably placebo, and by 125 fully nursing women who received a TCu 200 intrauterine contraceptive device. An exacting list of requirements for admission to and continuation in the study was applied to all groups. No pregnancies occurred in the progesterone-treated group from the second to the sixth postpartum month. This period coincided with the period of elevation plasma progesterone attributable to hormone released from the implants. The cumulative probability of pregnancy in the placebo group was 10.2 per 100 women at the sixth month. Treatment with progesterone did not change the duration of lactation or the rate of child growth, and no adverse effects were recorded. These results warrant further investagation of the use of progesterone as an alternative method to prevent conception in nursing women.

Endocrine profile in patients with chronic renal failure under zinc replacement

The plasma levels of androstenedione (A), testosterone (T), dihydrotestosterone (DHT), follicle stimulating hormone (FSH), luteinizing hormone (LH), and prolactin (PRL) were studied in 15 men (aged 24-50 years) with chronic renal failure under periodic peritoneal dialysis, before and after 50 mg of elemental zinc (Zn) orally, twice a day for three weeks. Before treatment, they were divided into three groups: group I, plasma A above normal and PRL less than 100 ng/ml; group II, low or normal A levels with PRL less than 100 ng/ml; and group III, normal or high A levels with PRL greater than 100 ng/ml. After oral Zn, plasma FSH, LH, and PRL were unchanged in all groups; however, in groups I and II plasma A was within normal T and DHT rose significantly, the A/(T+DHT) ratio decreased to normal, and the T/DHT ratio rose above normal. In group III plasma androgens remained low and androgen ratios were unchanged. Oral Zn seems to improve the conversion of A to T and also uncovered the possibility that plasma PRL levels greater than 100 ng/ml might cause a blockade in the 5 alfa-reductase.

Testicular function in men with chronic renal failure and transplant recipients under bromoergocriptine therapy

Plasma zinc (Zn), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), and androgens concentrations were determined in 15 male patients with chronic renal failure who were successful recipients of kidney transplant. After 25 +/- 8.5 months of the renal transplant, Zn levels were (88 +/- 4 g/dl) lower than in the control group (116 +/- 5 micrograms/dl). Normal concentrations for androstenedione (A) (0.63 +/- 0.05 ng/ml) and testosterone (T) (3.31 +/- 0.15 ng/ml) were found. Dihydrotestosterone (DHT) levels (0.38 +/- 0.01 ng/ml) were lower than normal (1.11 +/- 0.09 ng/ml), suggesting a blockade in the conversion of T to DHT. Eleven of the 15 patients showed higher PRL levels (9.5 +/- 0.8 ng/ml) in contrast with the normal group (3.6 +/- 0.3 ng/ml). Ten patients received orally 2-alpha-bromoergocriptine (BEC) 2.5 mg/day for ten days. Plasma PRL decreased to 2.6 +/- 1.0 ng/ml (p less than 0.001), but A and T levels did not significantly change; however, DHT increased from 0.38 +/- 0.02 ng/ml to 0.72 +/- 0.04 ng/ml (p less than 0.01). All patients showed an increase in both gonadotropins before BEC without significant changes after treatment. The high PRL levels may be responsible for the impaired conversion of T to DHT, possibly by interference with the enzyme 5 alpha-reductase.

Plasma progesterone levels following subdermal implantation of progesterone pellets in lactating women

The magnitude and duration of elevated plasma progesterone levels resulting from subdermal implantation of progesterone pellets were investigated in full nursing women. This condition was chosen because it is associated with a low rate of ovulation and minimal endogenous progesterone production. In addition, treatment with progesterone pellets was intended to be a substitute for oral or parenteral administration of synthetic progestogens to nursing mothers. A control group of full nursing women receiving no hormones provided blood samples so that basal plasma progesterone levels from the second to the sixth post-partum month could be assessed. Progesterone pellets were implanted subdermally on day 30-35 after delivery. Insertion of 2, 4 or 6 pellets each containing 100 mg of progesterone caused an initial elevation of plasma progesterone to 5.9, 9.9 and 13.5 nmol/l, respectively. This initial elevation was followed by a gradual decline, so that basal levels were attained at 70, 100 and 150 days after insertion of 2, 4 or 6 pellets. Implantation of 6 progesterone pellets led to a significant decrease in the ovulation rate of nursing women. These results indicate that subdermal implantation of 6 progesterone pellets can provide biologically effective levels of the hormone for up to 5 months.

Fertility regulation in nursing women: I. The probability of conception in full nursing women living in an urban setting

One hundred and thirty healthy women who were willing to breast-feed their babies were followed during the first postpartum year to assess their fertility, lactation and bleeding pattern and examine possible relationships between these variables. Seventy-five women were in full nursing and 22 in partial nursing at the end of the 6th postpartum month. Five hundred and three woman-months and nine pregnancies were recorded during full nursing between the 2nd and the 6th month after delivery. The cumulative probability of pregnancy at the end of 6 months in all full nursing women and in non-amenorrhoeic full nursing women was 10.0% and 27.2% respectively. The corresponding figure for partial nursing women was 40–5%.

By the end of the first year, the cumulative probability of pregnancy in full nursing women had increased to 33.9%. Except for the bleeding pattern, no differences were found among full nursing women who did or did not become pregnant.

It was concluded that full nursing women living in an urban setting who want to space pregnancies need additional protection at a time that depends upon the level of assurance wanted.

Zinc, prolactin, gonadotropins, and androgen levels in uremic men

This study correlates plasma levels of Zinc (Zn) and some pituitary and testicular hormones in 20 uremic men (aged 17-58 years) on a weekly peritoneal dialysis program. Patients were compared to 12 healthy male volunteers (aged 28-40 years). In uremic men, plasma androstenedione (A) was elevated, while testosterone (T), dihydrotestosterone (DHT), and Zn were low. On a group basis, plasma follicle stimulating hormone (FSH) and luteinizing hormone (LH) were normal while prolactin was increased. A negative correlation was observed between plasma A and LH levels, as well as between the A/T+DHT ratio and plasma Zn concentrations. Our results suggest a diminished A-to-T conversion and point to the possible role of Zn in the enzyme activity of the 17 beta-hydroxysteroid dehydrogenase.

[Changes in the nutritional status of the lactating women during exclusive lactation]

In order to evaluate the influence of breast feeding upon selected nutritional parameters of lactating women, several anthropometric and biochemical measurements were performed during the interval between 40 and 180 postpartum days in 54 women in full and satisfactory nursing. Only one significant change was detected in measurements done for nutritional assessment: loss of body weight. No changes were detected in hemoglobin levels or in serum protein and albumin. There was high variability in body weight changes with a mean loss of 1.5 kg due especially to a loss in fat body mass and, in a lesser proportion, to loss in lean body mass. The mean food intake did not change during the observation period. The mean caloric intake was 2,771 cal/day at the beginning and 2,737 cal/day in the end of the study. A significant correlation was established between the individual energetic intake and the body weight changes of lactating women. The allowance of 2,750 cal/day suggested by FAO/WHO for lactating women seems adequate for the health of women in a normal nutritional condition, but apparently insufficient to overcome undernutrition in women who initiate lactation with this condition. In spite of the small nutritional impact observed, our results support the need for food supplementation programs destined to lactating women, with special orientation to undernourished women of low socioeconomic level.

Plasma levels of levonorgestrel in women during longterm use of norplant

Levonorgestrel plasma levels were determined by a specific radioimmunoassay in a group of 110 women at various intervals between 1 and 60 months following implantation of six silastic capsules containing levonorgestrel (Norplant). The implants were placed subdermally in the volar aspect of the forearm. Blood samples were taken twice a week for six consecutive weeks in each subject. Blood drawn from the antecubital vein ipsilateral to the implant site contained two to three times more levonorgestrel than contralateral samples. Average systemic plasma levels represented by contralateral samples ranged from 0.35 +/- 0.03 to 0.29 +/- 0.02 ng/ml (Mean +/- S.E.) in the first and fifth year, respectively. The difference between these values is statistically significant at the 5% level. The results of the regression analysis of individual levels suggest that the decline observed throughout the first five years is mainly due to an early decrease taking place in the first two years. When the sampling period was repeated in the same subjects two or three times 10 to 24 months apart, no significant difference was found. A significant negative correlation was found between plasma levonorgestrel levels and body weight and body surface. The data indicate that the contraceptive efficacy of Norplant during the first five years of use is associated with sustained release of levonorgestrel and is in keeping with the estimated life span of Norplant of seven years.

Plasma levels of levonorgestrel in women during longterm use of Norplants

Levonorgestrel plasma levels were determined by a specific radioimmunoassay in a group of 110 women at various intervals between 1 and 60 months following implantation of six silastic capsules containing levonorgestrel (Norplant). The implants were placed subdermally in the anterior aspect of the forearm. Blood samples were taken twice a week for six consecutive weeks in each subject. Blood drawn from the antecubital vein ipsilateral to the implant site contained two to three times more levonorgestrel than contralateral samples. Average systemic plasma levels represented by contralateral samples ranged from 0.35 +/- 0.03 to 0.29 +/- 0.02 ng/ml (Mean +/- S.E.) in the first and fifth year, respectively. The difference between these values is statistically significant at the 6% level. The results of the regression analysis of individual levels suggest that the decline observed throughout the first five years is mainly due to an early decrease taking place in the first two years. When the sampling period was repeated in the same subjects two or three times 10 to 24 months apart, no significant difference was found. A significant negative correlation was found between plasma levonorgestrel levels and body weight and body surface. The data indicate that the contraceptive efficacy of Norplants during the first five years of use is associated with sustained release of levonorgestrel and is in keeping with the estimated life span of Norplants of seven years.

Ectopic pregnancies associated with low dose progestagen-releasing IUDs

Dimethyl-polysiloxane capsules containing pure progestagens were attached to Tatum's T IUDs and tested in 594 fertile women for contraceptive performance. The control group was represented by 71 women who received identical devices containing barium sulphate instead of steroid and 100 women who received a Copper T-200. The progestagens and the doses tested were megestrol acetate (4.8, 19.2, 26 and 32 micrograms/day; levonorgestrel (2.1, 3.4 and 8.5 micrograms/day); norethindrone (18 micrograms/day); R2323 (28.6 and 45 micrograms/day); and norgestrienone (26 micrograms/day). Twelve pregnancies were diagnosed during 5201 woman-months of exposure accumulated within the first year of use among users of the steroid-bearing IUDs. Five of these were ectopic gestations. Ten pregnancies, all uterine, were detected during 1701 woman-months of exposure in the control group. Intrauterine delivery of progestagens by means of a carrier IUD is effective in decreasing the pregnancy rate but it might effect postovulatory events in a way which increases the rate of tubal implantation. Because of this property, progestagen-releasing IUDs should be limited to doses that assure maximal effectiveness to avoid increasing the risk of ectopic pregnancy.

Studies on the duration of ovum transport by the human oviduct. III. Time interval between the luteinizing hormone peak and recovery of ova by transcervical flushing of the uterus in normal women

This article deals with attempts to time the onset and duration of the ovum's sojourn in the endometrial cavity of women. Recovery of the ovum from the uterus was attempted by means of transcervical flushing of the cavity 48 to 216 hours after the luteinizing hormone (LH) peak in plasma. A single flushing or repetitive flushings done at 24-hour intervals in the same cycle were performed in different subjects. With both modalities, the adverse effects were mild and few. Of 132 flushings done in 76 subjects, 90 were considered to be technically adequate from the point of view of recovering over 50% of the flushing volume. Twenty ova were recovered. Technically adequate flushings and adequate timing of the LH peak were accomplished in 39 cycles. In this group, 13 ova were recovered between 96 and 168 hours after the LH peak. The highest yield of ova per flushing was obtained from 120 to 168 hours with an average of 37% and a range of 25% to 50%. Limitations of the technique are discussed. Some uncertainties persist which prevent the drawing of definitive conclusions about how soon after the LH peak the egg enters the uterine cavity, how long it stays there, and what is the extent of individual variation. However, recovery rates at various times after ovulation agree with previous data derived from transfundal flushing and indicate that the ovum is usually transferred to the uterus between 96 and 120 hours after the LH peak is retained there for several days.