Average Progesterone Levels Research Articles

Effect of different levels of serum progesterone on day of frozen ET on clinical outcome

BackgroundProgesterone (P4) plays a critical role in a natural menstrual cycle. It is an essential hormone to have successful embryo implantation into the endometrium.ObjectiveIn the current study, we compared the clinical outcomes of patients with different levels of P4 on embryo transfer day and aimed to determine the optimum threshold for P4 in the luteal phase.Material and methodsWe performed a prospective cohort study on 100 patients who were referred to the Taleqani Infertility Treatment Institute to undergo frozen embryo transfer (FET). Endometrial preparation was programmed using an estrogen (E2) and progesterone supplement. FET was carried out 3 days after administration of the first dosage of progesterone. We measured serum progesterone levels on embryo transfer day. Clinical pregnancy was the main investigated outcome. We used a parametric receiver operating characteristic curve (ROC) to determine the best-cut points of P4 on embryo transfer day.ResultsOverall, the average endometrial thickness was 7.9 ± 0.2 mm. We observed no association between endometrial thickness and clinical pregnancy (P value = 0.719). The mean number of the transferred embryos in all investigated cycles was 1.5 ± 0.5, and 80.0% of the transferred embryos were high quality (high and medium level). The average progesterone level in cycles with clinical pregnancy was 17.2 ± 3.3 ng/mL. It was only 13.4 ± 9.4 in patients without clinical pregnancy. The observed difference was statistically significant (P value = 0.032). The estimated AUC for the drawn ROC curve was 0.71 indicating a high predictive value.ConclusionThe current study demonstrated that high and low serum progesterone (P4) levels on embryo transfer day were associated with reduced clinical outcomes following blastocyst transfer during IVF/ICSI. However, more studies with large sizes are required in this regard.

Differential effects of western versus mediterranean diets and psychosocial stress on ovarian function in female monkeys (Macaca fascicularis)

Ovarian dysfunction increases risk for chronic diseases of aging including cardiovascular disease, depression, cognitive impairment, as well as bone and muscle loss which promote frailty. Psychosocial stress can disrupt ovarian function, and recent observations suggest that consumption of a Western Diet may also. Determination of causal relationships among diet, psychosocial stress, and ovarian physiology is difficult in humans. Long-tailed (a.k.a. cynomolgus) macaques (Macaca fascicularis) are an excellent translational model for the study of diet and psychosocial effects on ovarian physiology and aging-related processes. They have 28-day menstrual cycles with hormonal fluctuations like those of women, and similar physiologic responses to alterations and/or cessation of cyclicity. We examined ovarian function in 38 middle-aged socially housed females fed either a Western or Mediterranean diet for 31 months (≈ a 9-year period for humans). During the last year, we examined cycle length and peak progesterone per cycle using blood sampling (3/week) and vaginal swabbing for menses (6/week). Repeated measures analysis revealed a circannual pattern consistent with increased menstrual cycle disturbance during the late Summer and early Fall (F(11,348)= 4.05 p < 0.001). In addition, both Western diet (F(1,34)= 3.99; p = 0.05) and the stress of low social status (F(1,34)= 3.99; p = 0.04) reduced mean progesterone levels. Thus, on average, subordinates in the Western group had the lowest average progesterone levels (10.02 ng/pl). Compared to Western diets, Mediterranean diets exhibited protective effects via menstrual cycle regularity. For dominant monkeys, consuming Mediterranean diets resulted in significantly greater likelihood of having regular menstrual cycles. Mediterranean diets also protected individuals from shorter than normal menstrual cycles. The relationships between diet and menstrual regularity were partially mediated by both adrenal reactivity and social isolation. This study demonstrates the additive negative effects of poor diet and psychosocial stress on ovarian physiology in mid-life and lays the groundwork for future investigations to uncover their impact on metabolic signatures of accelerated aging. The results also suggest that – compared to Western-style diets - a Mediterranean diet may exert a protective influence against ovarian dysfunction and its pathologic sequelae.

Salivary Progesterone Levels in Female Patients with a History of Idiopathic Scoliosis: A Retrospective Cross-Sectional Study.

Idiopathic scoliosis is a condition characterized by a three-dimensional curvature of the spine. However, in addition to the spinal curvature, it has also been reported that patients with idiopathic scoliosis can display other abnormal physiologic parameters, such as hormone imbalances, genetic variants, and micronutrient deficiencies. The present study evaluates the salivary progesterone levels from a historical cohort of patients seeking treatment at a single integrative medicine clinic. A group of female patients with a history of idiopathic scoliosis is compared to a group of non-scoliosis female patients. Salivary progesterone levels were 49% higher in non-scoliosis patients compared to the scoliosis group (p < 0.05). When compared by the menstrual cycling status, non-scoliosis females had a 60% higher average progesterone level, while the progesterone level among non-cycling, non-scoliosis females was 39% higher than non-cycling scoliosis females. These results suggest a potential relationship between salivary progesterone and idiopathic scoliosis among female patients.

Effect of progesterone on hCG day-to-basal progesterone ratio on live birth rate in long agonist fresh IVF/ICSI cycles: a 5-year, single-center study of more than 10,000 cycles

Objective To investigate whether the ratio of the serum progesterone level on the day of human chorionic gonadotrophin (hCG) administration to the basal serum progesterone level (PhCG/Pbasal) is a predictor of pregnancy outcome during in vitro fertilization (IVF). Methods A total of 12,708 cycles were performed in 9747 patients between 19 and 36 years of age who were undergoing controlled ovarian stimulation from October 2011 to July 2016 for their first or second attempts at IVF followed by fresh embryo transfer (ET). hCG was administered 36 h before oocyte retrieval to trigger final oocyte maturation. The serum progesterone level was measured on menstrual cycle days 2-4 (basal progesterone, Pbasal) and on the day of hCG administration (PhCG). PhCG/Pbasal was calculated. Live birth rates were compared among various ordinal PhCG/Pbasal intervals (< 0.5, 0.5–1.0, 1.0–1.5, 1.5–2.0, 2.0–2.5, > 2.5). Results The average age of the patients recruited was 29.9 years. The average basal progesterone level was 0.8 ng/ml, while the average progesterone level on the day of hCG administration was 0.9 ng/ml. The live birth rates (according to the abovementioned ordinal PhCG/Pbasal intervals) were 47.3, 49.9, 47.8, 46.3, 45.5 and 44.0%, respectively. The live birth rates were significantly higher for patients with PhCG/Pbasal between 0.5–1.0 (OR = 1.14, 95% CI, 1.02–1.27, p = .02). Conclusions PhCG/Pbasal between 0.5-1.0 predicts a higher live birth rate in IVF. Both PhCG/Pbasal and P on hCG day is less predictive value for predicting live birth rate.

Does the interaction between partnership status and average progesterone level predict women's preferences for facial masculinity?

Many studies have attempted to identify biological factors that reliably predict individual differences in women's preferences for masculine male faces. Marcinkowska et al. (2018, Hormones & Behavior) recently reported that women's (N = 102) preferences for facial masculinity were predicted by the interaction between their relationship status (partnered versus unpartnered) and average progesterone level. Because previous findings for between-women differences in masculinity preferences have often not replicated well, we attempted to replicate Marcinkowska et al.'s result in an open data set from another recent study that had not tested this hypothesis (Jones et al., 2018, Psychological Science). In this sample of 316 women, we found that facial masculinity preferences were predicted by the interaction between women's relationship status and average progesterone level, consistent with Marcinkowska et al.'s results (data and analysis code are available at https://osf.io/q9szc). Together, these findings suggest that the combined effects of relationship status and average progesterone level may predict facial masculinity preferences relatively reliably.

Early pregnancy diagnosis of captive Amur tigers (Panthera tigris altaica)

From January 2015 to February 2017, urine samples was collected from twelve captive female Amur tigers during both their mating (or receptive) periods and the first four weeks after mating at the Hengdaohezi Feline Breeding Center (FBC) in China. A radioimmunoassay was applied to determine the progesterone levels in the urine samples. The relationship between progesterone levels and pregnancy in Amur tigers was assessed according to whether the tigers gave birth in the end. Results showed that average progesterone levels increased significantly (P < .05) after mating for all female tigers having parturition. And the minimum value of progesterone levels of them during the fourth week after mating was consistently higher than 0.21 ng/mL, the maximum value in mating period of all female tigers. However, there were no significant differences in progesterone levels between mating period and the first four weeks after mating of the female tigers having no parturition. Therefore, early pregnancy in captive Amur tigers can be diagnosed when urine progesterone concentrations attain a level higher than 0.21 ng/mL for seven days in a row after mating.

English

Progesterone is an endogenous hormone secreted by ovaries that prepares uterine endometrium for implantation. The aim of this study was to evaluate the relation of serum progesterone level on the day of transferring frozen embryo with pregnancy occurrence. MATERIALS AND METHODS 161 women were chosen for frozen embryo transfer. From the second day of their cycle, they were treated with 2 mg per 8 hours estradiol. From the 13th day, 5 mg intramuscular (IM) progesterone was injected every 12 hours to increase endometrium thickness above 8 mm. 4 days after progesterone administration, embryo transfer was performed, and progesterone level was measured. Pregnancy occurrence was also evaluated. RESULTS The average progesterone level in 25 women with positive beta HCG was 26.26 +/- 8.58 on 1st day, 26.63 +/- 8.22 on 17th day and 24.3 +/- 11.48 on the 18th day of transfer. In 136 non-pregnant women it was 25.61 +/- 16.01 on 1st day, 29.03 +/- 14.45 on 17th day and 15.42 +/- 2.77 on 18th day. CONCLUSION There was no relationship between serum level of progesterone on the day of transfer and pregnancy occurrence.

Average ovarian hormone levels, rather than daily values and their fluctuations, are related to facial preferences among women

Hormones are of crucial importance for human behavior. Cyclical changes of ovarian hormones throughout women's menstrual cycle are suggested to underlie fluctuation in masculinity preference for both faces and bodies. In this study we tested this hypothesis based on daily measurements of estradiol and progesterone throughout menstrual cycle, and multiple measurements of women's preference towards masculinity of faces and bodies of men. We expected that due to a large variation among daily hormonal levels we would not observe a direct effect of daily hormone levels, but rather that average levels of ovarian hormones throughout the cycle (a reliable marker of a probability of conception) would better predict women's preferences. We found a negative relationship between average progesterone levels and facial masculinity preference, but only among women who were in long-term relationships. There was no relationship between facial masculinity preference and either of the estradiol or progesterone daily levels. Similarly, only average levels of hormones were significantly related to facial symmetry preference. For women who were in relationships estradiol was positively related to symmetry preference, while for single women this relationship was opposite. For body masculinity preference there were no significant relationships with neither averaged nor daily hormonal levels. Taken together, our results further suggest that overall cycle levels of ovarian hormones (averaged for a cycle) are better predictors of facial masculinity and symmetry preference than daily levels assessed during preferences' tests. Importantly, including information about relationship status in the investigations of hormonal bases of preferences is crucial.

Progesterone and women's anxiety across the menstrual cycle

Animal models and a few human investigations suggest progesterone may be associated with anxiety. Progesterone naturally fluctuates across the menstrual cycle, offering an opportunity to understand how within-person increases in progesterone and average progesterone levels across the cycle correspond to women's anxiety. Across two longitudinal studies, we simultaneously modeled the between- and within-person associations between progesterone and anxiety using multilevel modeling. In Study 1, 100 Polish women provided saliva samples and reported their anxiety at three phases of the menstrual cycle: follicular, peri-ovulatory, and luteal. A significant between-person effect emerged, revealing that women with higher average progesterone levels across their cycles reported higher levels of anxiety than women with lower progesterone cycles. This effect held controlling for estradiol. In Study 2, 61 American women provided saliva samples and reported their attachment anxiety during laboratory sessions during the same three cycle phases. A significant between-person and within-person association emerged: women with higher average progesterone levels reported higher levels of attachment anxiety, and as women's progesterone levels increased across their cycles, so too did their attachment anxiety. These effects held controlling for cortisol. In sum, both studies provide support for a link between menstrual cycle progesterone levels and subjective anxiety.

Pemberian makanan pengganti cair Nutrisure Gold® tidak meningkatkan kadar hormon estrogen tetapi meningkatkan kadar hormon progesteron pada anak tikus putih (Rattus norvegicus) galur Wistar betina

Abstract: One of the factors that influences aging process is hormonal imbalance that can occur due to the intake of food or drink containing hormone. Children aged more than 1 year with difficulty in eating are usually given Nutrisure Gold®. Analysis has shown that Nutrisure Gold® contains estrogen dan progesterone. This study was aimed to prove that Nutrisure Gold® could increase estrogen and progesterone levels in Wistar female rats. This was an experimental study with the post test only control group design. Subjects were 36 female Wistar rats (Rattus norvegicus) aged 21 days divide into 2 groups, each of 18 rats. The control group was given white rice 3.11 g and aqua bidest meanwhile the treatment group was given Nutrisure Gold® 0.93 g three times a day for 28 days. The results showed that the average estrogen level in the control group was 44.26±11.49 pg/ml and of the treatment group was 45.30±7.66 pg/ml. The average progesterone level in the control group was 22.43±3.62 ng/ml and of the treatment group was 27.44±2.28 ng/ml. Data of estrogen level were analyzed with t-independent test that showed t = -0.320 and P = 0.751 (P &gt;0.05) meanwhile of progesterone level showed t = -4.978 and P = 0.000 (P &lt;0.05). Conclusion: After treatment, the average estrogen levels in both groups did not differ significantly meanwhile the average progesterone levels in both groups showed significant difference.Keywords: liquid replacement meal, estrogen, progesteroneAbstrak: Salah satu faktor yang memengaruhi proses penuaan ialah ketidak seimbangan hormon yang dapat terjadi antara lain akibat pemberian asupan makanan atau minuman yang mengandung hormon. Anak-anak berusia satu tahun ke atas dengan masalah sulit makan sering diberikan makanan pengganti cair Nutrisure Gold®. Analisis menunjukkan bahwa Nutrisure Gold® mengandung hormon estrogen dan progesteron. Penelitian ini bertujuan untuk membuktikan bahwa pemberian Nutrisure Gold® meningkatkan kadar hormon estrogen dan progesteron pada tikus putih galur Wistar betina umur 21 hari. Jenis penelitian ialah eksperimental dengan post test only control group design, Subyek penelitian ialah 36 ekor tikus putih (Rattus norvegicus) galur Wistar betina umur 21 hari yang dibagi atas 2 kelompok, masing-masing kelompok terdiri dari 18 ekor. Kelompok kontrol diberikan nasi putih 3,11 gr dan aquabides sedangkan kelompok perlakuan diberikan Nutrisure Gold® 0,93 gr 3 kali sehari selama 28 hari. Hasil penelitian menunjukkan rerata kadar estrogen kelompok kontrol 44,26±11,49 pg/ml dan rerata kelompok perlakuan 45,30±7,66 pg/ml. Rerata kadar progesteron kelompok kontrol 22,43±3,62 ng/ml dan rerata kelompok perlakuan 27,44±2,28 ng/ml. Analisis kemaknaan kadar estrogen dengan uji t-independent menunjukkan t = -0.320 dan p = 0,751 (P &gt;0,05). Analisis kemaknaan kadar progesteron dengan uji t independent menunjukkan nilai t = -4,978 dan p = 0.000 (P &lt; 0,05). Simpulan: Setelah diberi perlakuan, rerata kadar estrogen pada kedua kelompok tidak berbeda bermakna tetapi rerata kadar progesteron pada kedua kelompok menunjukkan perbedaan bermakna.Kata kunci: makanan pengganti cair, estrogen, progesteron

Estrous Synchronization with Used CIDR-G Devices in Ewes During Non-Breeding Season

Summary The objective of this study was to investigate the efficacy of used controlled internal drug release devices (CIDR-G) on estrous synchronization in ewes. This investigation was conducted in 58 fat-tailed ewes during the non-breeding season. Ewes were divided in to four groups. In Group I, CIDR-G devices were inserted to vagina for 12 d (CIDR group). In Group II, previously used CIDR-G devices were inserted into the vagina for 12 d (U-CIDR). After the intravaginal devices had been removed 500 IU equine chorionic gonadotropin (eCG) was injected intramuscularly (i.m.) into ewes of the CIDR and U-CIDR groups. Ewes in Group III (eCG group), 500 IU eCG was injected im. Ewes in Group IV, served as control and received an injection of 3 mL 0.9% NaCl (C Group). None of the control ewes expressed estrus. It was found that, 13/15 (86.67%), 10/15 (66.67%) and 1/13 (7.69%) ewes expressed estrus in CIDR, U-CIDR and eCG groups, respectively. The pregnancy rates in the CIDR, U-CIDR and eCG groups were 8/15 (53.33%), 9/15 (60%) and 1/13 (7.69%) at first breeding, respectively. The interval from eCG application to onset of estrus was 42.6±1.01, 40.13±1.35 and 74 h in the CIDR, U-CIDR and eCG groups, respectively. Average progesterone (P4) levels during P4 treatment were 3.28±0.28 and 2.62±0.14 ng/ml in the CIDR and U-CIDR groups, respectively. It is concluded that, CIDR-G that have been previously used for 12 d could be used for the synchroniation of estrus in ewes during non-breeding season.

The use of a new logistic regression model for predicting the outcome of pregnancies of unknown location.

The aim of this study was to generate and evaluate new logistic regression models from simple demographic and hormonal data to predict the outcome of pregnancies of unknown location (PULs). Data were collected prospectively from 185 consecutive women classified as having a PUL by transvaginal scan; blood was taken at presentation and 48 h later to measure serum progesterone and HCG. These women were followed-up until the outcome was established: an intrauterine pregnancy (IUP), an ectopic pregnancy (EP) or a failing PUL. Three multi-categorical logistic regression models were tested. M1 was based on the HCG ratio (rate of change in HCG over 48 h), M2 was based on the average progesterone level (the mean of the progesterone level at 0 and 48 h) and M3 was based on the patient's age. A total of 102 failing PULs, 63 IUPs and 20 EPs were used in the training set to develop the new models. The best of these models, M3, gave a retrospective area under the receiver operating characteristic (ROC) curve of 0.984 for failing PUL, 0.995 for IUP and 0.920 for EP. All three models were tested prospectively on the test set of 196 cases. M1 outperformed M2 and M3 when tested prospectively. The area under the ROC curve (AUC) was 0.975 for failing PUL, 0.966 for IUP and 0.885 for EP. M1, for the detection of EP, had a sensitivity of 91.7%, a specificity of 84.2%, a positive likelihood ratio of 5.8, a positive predictive value of 27.5% and a negative predictive value of 99.4%. The logistic regression model M1, can predict which PULs will become failing PULs, IUPs and, most importantly, EPs based on the patient's HCG ratio alone.

The relationship between the blood progesterone concentration at early metoestrus and uterine infection in the sow

Abstract In a previous study it was shown that gilts inoculated in the uterus during standing oestrus had a better resistance to Escherichia coli infections than gilts that were similarly inoculated within 12 h after the end of the standing reflex (De Winter et al., 1992). In the present study, the changes of blood progesterone concentrations during early metoestrus were investigated. It was also investigated to what extent the onset of endometritis after intrauterine inoculation is correlated to the blood progesterone concentration. In a preliminary study, the plasma progesterone concentration was measured in a group of 11 gilts during early metoestrus, in order to evaluate the average progesterone levels at that stage of the oestrous cycle. A wide variation of blood progesterone concentrations was observed. A second group of 13 gilts was inoculated in the uterus with an E. coli suspension in order to investigate the presence of a correlation between blood progesterone level and susceptibility of the porcine uterus to bacterial endometritis. A third group of six gilts was similarly inoculated with Staphylococcus hyicus. A clear correlation between blood progesterone concentration and susceptibility to endometritis and the development of a vaginal discharge in gilts experimentally inoculated was observed. The gilts with a low blood progesterone concentration at the time of inoculation had less vaginal discharge and a better resistance to endometritis than gilts with a higher blood progesterone concentration. In gilts inoculated with E. coli, as well as those inoculated with S. hyicus, a significant correlation (P

Prostaglandin E 2 and progesterone during the estrous cycle of the pig

The possible role of endogenous PGE 2 in corpus luteum function during the estrous cycle of the pig was examined. A catheter was placed in an ovarian vein of each of three sows and in the posterior vena cava of six gilts. Blood samples were collected twice daily. Blood was also collected every 10 min for 6 h from the sows and for 12 h from the gilts during early, mid and late estrous cycle. In the sows, average serum PGE 2 levels tended to be higher on days 2 and 9 than on day 16 postestrus ( P < 0.1). Average PGE 2 levels in the gilts were higher during the late phase than during the early and mid phases of the cycle ( P < 0.05). Average progesterone levels in both the sows and the gilts were several fold higher during the mid phase than during the early and late phases of the cycle. Results from this study do not support the hypothesis that endogenous PGE 2 is antiluteolytic because the average PGE 2 levels in the gilts and sows were either higher or not lower during the regression phase of the corpus luteum than during earlier stages of the cycle.

Plasma concentrations of progesterone during oestrous cycles of ethiopian menz sheep using enzyme immunoassay

Plasma progesterone concentrations were assessed with a commercially available ELISA technique in 20 Ethiopian Menz ewes during their oestrous cycles which averaged 17.2 ± 1.0 (range 15–20) days ( n=36). Average progesterone levels were significantly ( P<0.0001) different between ewes (range 2.43–4.80 ng/ml) and days ( P<0.0001) of their oestrous cycles (0.32–5.84 ng/ml). Progesterone values were under 1.0 ng/ml from 2 days before to 4 days after oestrus. Hormone concentration rose steadily to peak at 5.0–5.6 ng/ml on days 10 to 14. This was followed by a rapid decline to 3.0 ng/ml (53% of day 14 peak value) on day 15; 0.8 ng/ml (15% of peak value) on day 16; and 0.2 ng/ml (3.7%) on the day before oestrus. It is concluded that the ELISA method can be used for progesterone determination in Ethiopian sheep, and also, that progesterone levels of under 1.0 ng/ml are indicative of either anoestrous or the follicular and early luteal phases of the oestrous cycle.

Low profiles of salivary progesterone among college undergraduate women

High incidences of amenorrhea and oligomenorrhea are often found among late adolescent, college-aged women. We studied menstrual profiles of salivary progesterone in 17 undergraduate women (average age 20.2 years) who were experiencing regular menstrual cycles, and compared the results with similar data obtained from older women, both recreational runners (30.7 years) and nonexercising controls (29.3 years), to see whether this late adolescent population showed evidence of compromised luteal function not manifested by menstrual irregularity. The profiles obtained from the undergraduates and the older women were similar in shape but different in level. The undergraduate profiles were significantly lower than the controls (average progesterone level during the luteal phase, 154 ± 14 versus 287 ± 30 pmol/L; peak progesterone level, 352 ± 35 versus 655 ± 46 pmol/L; mean ± SE, p < 0.01), and remained at a significantly elevated level for fewer days (1.3 ± 0.4 versus 4.5 ± 0.6 days, p < 0.01). The undergraduates were more comparable in all measures to the older women runners; however, reported exercise and weight differences did not account for the low levels in the undergraduates. We suggest that the low progesterone levels in the undergraduates reflect an extended process of ovarian maturation that does not culminate until the mid to late twenties.

Immunosuppression, sialic acid, and sialyltransferase of bovine serum as a function of progesterone concentration

Serum samples from progesterone-oestrogen-treated ovariectomized Holstein cows (N = 4) were compared with samples from control ovariectomized Holstein cows (N = 4) to determine the effects of physiological levels (0-6 ng/ml) of circulating progesterone. The average progesterone level in treated animals rose from 1 ng/ml (Day 0) to plateau at 5 ng/ml (Days 12 to 36). Sera from progesterone-oestrogen-treated cows during Days 4 to 10 significantly suppressed stimulation of lymphocytes by phytohaemagglutinin as compared with sera from control cows (P = 0.02), whereas no differences were detected in serum samples from Days 12 to 36. Serum samples from progesterone-oestrogen-treated or control cows did not affect the stimulation of lymphocytes by pokeweed mitogen. Sialyltransferase activity (P = 0.0002) and sialic acid content (P = 0.006) were both significantly elevated in serum from progesterone-oestrogen-treated animals compared with controls during Days 8 to 16, whereas no significant differences were observed at later times. The results suggest that suppression of phytohaemagglutinin-induced stimulation, sialic acid content, and sialyltransferase activity are sensitive not to the circulating level of progesterone but rather to increases in progesterone concentration, with maximal effects observed at Days 8, 12 and 12, respectively, after the start of progesterone treatment. The work provides a preliminary basis for further studies on the mechanism of immunosuppression by steroids and during pregnancy.

Various coagulation techniques tested in a rabbit model. Results of morphological and endocrinological studies.

CO2- pelviscopies or laparotomies were performed in 370 New Zealand white rabbits and were followed by coagulation of the distal uterine horns with unipolar, bipolar, endo- or CO2-laser coagulation. After 1, 2, 4, 8 or 12 weeks laparotomy was carried out and, following macroscopic description, photo documentation and measurement of the destroyed region, the uterine horns were excised. In addition to the normal histological and electromicroscopic evaluation, 5 mu thick cryostat sections were screened for the presence of nine different enzymes. Attempts were made not only to determine the extent of the destroyed zone, but also to obtain additional information on damage to the vascular and nervous systems of the tubes and ovaries. Progesterone levels were determined in 49 New Zealand rabbits before and after stimulation with 50 I.U. HCG i.v. We were able to show that there is a definite correlation between the type of coagulation technique and the extent of the destruction zone. The average progesterone levels of the animals coagulated using the monopolar high-frequency technique, were significantly lower than the hormone levels in the endocoagulation, bipolar or control group.

Control of estrus and progesterone levels in heifers given intravaginal progesterone coils and injections of progesterone and estrogen.

Fifty-three mature Hereford-cross heifers, which were between day 0 and 3 of the estrous cycle, each had silastic coils containing 2.1 g progesterone inserted into the vagina where they remained for 12 days. Animals were assigned to treatment groups and were injected with (1) 5 mg estradiol benzoate, (2) as (1) + 50 mg progesterone or (3) as (1) + 200 mg progesterone at the time of insertion of the coils. Blood samples were taken for radioimmunoassay of progesterone in plasma before insertion and daily while the coils were in the vagina. There were no differences among treatments in the percentage of heifers observed in estrus from days 1 to 6 after removal of the coils, but a greater percentage of animals in treatments 1 and 3 than in treat 2 were in estrus within 2 days of removal of the coils (P<.05). The mean daily plasma levels of progesterone during treatment for animals on the different treatments, which were in estrus within 2 days removal of the coils were not different. However, for animals in treatment groups 1 and 2 lower average progesterone levels over the first 2 days after insertion appeared to be associated with poor synchronization. The level of progesterone over the last 3 days of treatment was significantly related to the interval from removal of coils to onset of estrus for all heifers (P<.01).