Modifications in uterine and intraovarian artery impedance in cycles of treatment with exogenous gonadotropins: effects of luteal phase support

Effect of exogenous estradiol Benzoate on uterine blood flow in postpartum dairy cows

The objective of this study was to assess the uterine blood flow following estradiol benzoate administration in Holstein-Friesian dairy cows by trans-rectal color Doppler ultrasonography. Six healthy lactating Holstein-Friesian cows were examined daily for 10 days starting at 4 weeks postpartum. All the cows, which were clinically healthy based on vaginal mucus scoring and endometrial cytology, were examined by trans-rectal Doppler ultrasonography to measure pulsatility index (PI), resistance index (RI), time average maximum velocity (TAMAX), blood flow volume (BFV) and diameter in the uterine arteries ipsilateral and contralateral to the previously pregnant uterine horn. On the third day of the experiment, the six cows were administered 10 mg intramuscular injection of estradiol-17β (E₂).Blood samples were collected at the time of daily examination for the assessment ofE₂concentrations.The PI and RI values decreased while TAMAX, BFV and diameter of uterine arteries increased in response toE₂ administration (P < 0.05).There was a high correlation between both the ipsilateral and contralateral uterine arteries for all variables that were studied(r = 0.860, P < 0.0001, r = 0.922, P < 0.0001, r = 0.651, P < 0.0001, r = 0.879, P < 0.0001, r = 0.861, P < 0.0001 for the PI, RI, TAMAX, BFV and uterine arteries diameter, respectively).In conclusion, the greater blood concentrations ofE₂may be responsible for the greater TAMAX, BFV, increased diameters and decreased PI and RI of the uterine arteries during the puerperium in dairy cows.

A comparative analysis of arterial blood flow in unexplained infertility, tubal infertility and fertile groups

We aimed to compare ovarian (O), uterine (U) and spiral (S) artery (A) resistance of patients diagnosed as fertile, unexplained infertility (UI) and tubal factor infertility (TFI) in the peri-implantation period and independent from the impact of the treatment. UI (n = 70), TFI (n = 75) and fertile (n = 72) patients' ovarian, uterine and spiral artery pulsatility index (PI), resistance index (RI) and the endometrial thickness, serum estradiol and progesterone levels were compared. The specificity and sensitivity values were calculated according to determined cutoff values. Both TFI and control groups' UA PI values were significantly lower than the UI group's PI values. The highest UA RI values were found in UI group and the lowest values were in the control group. UI and TFI groups' OA PI/RI values were significantly higher than the control group. Both the control and TFI groups' SA PI/RI values were significantly lower than UI group's PI/RI values. UI patients' uterine and spiral arteries PI values >1.86 and >0.85, RI values >0.80 and >0.53 can be used as a valuable test showing reduced uterine perfusion. Ovarian artery PI values  >0.96 and RI values  >0.58 can be used as tests showing decreased ovarian perfusion in patients with TFI. In these patients, embryo cryopreservation can be considered.

The effect of exogenous estradiol benzoate and altrenogest on uterine and ovarian blood flow during the estrous cycle in mares

In recent years, a positive relationship between genital perfusion and fertility has been established; in species other than horses, uterine and ovarian perfusion was improved by exogenous estrogen but impaired by exogenous progestin. The goal of the present study was to investigate the effect of exogenous estrogen and progestin on uterine and ovarian blood flow in cycling mares. Five Trotter mares were examined daily during three estrous cycles. Mares were given no treatment, altrenogest (0.044 mg/kg BW) orally from Day 0 (ovulation) to Day 14 and estradiol benzoate (5mg i.m.) on Days 0, 5, and 10, in three cycles, respectively. There was no difference ( P > 0.05 ) in the length of untreated versus estrogen-treated cycles ( 22.8 +/-1.3 days and 23.2 +/= 1.5 days, respectively), but cycle length was increased (P < 0.05) in progestin-treated cycles (26.0 +/- 1.2). To facilitate comparisons among cycles with different lengths, data from Days 0 to 15 (diestrus) and from Days -6 to -1 (estrus) were analyzed. Transrectal Doppler sonography was used to evaluate blood flow in both uterine arteries and in the ovarian artery ipsilateral to the preovulatory follicle during estrus and ipsilateral to the corpus luteum during diestrus. Blood flow was assessed semiquantitatively using the pulsatility index (PI); high PI values indicated high resistance and a low perfusion and vice versa. An immediate effect of treatments occurred only after the administration of estradiol benzoate on Day 0; uterine PI values decreased (P < 0.05) between Days 0 and 1 and estrogen-treated mares but increased (P < 0.05) at the corresponding time in untreated cycles. Mean PI values for the uterine and ovarian arteries during both diestrus and estrus were higher (P < 0.05) in estrogen-treated versus untreated mares. Furthermore, mean uterine PI values during diestrus and estrus were higher (P< 0.05) in altrenogest-treated versus untreated mares. Neither estrogen nor altrenogest treatments had a significant immediate effect on ovarian PI values. Compared to untreated cycles, mean ovarian PI values were elevated (P < 0.05) only in the estrus following altrenogest administration. In conclusion, exogenous estrogen and progestin both decreased genital perfusion in cycling mares.

Hemodynamic effects of transdermal estradiol alone and combined with norethisterone acetate

A 24 weeks, randomized, two-period, placebo controlled study was conducted to compare the effects of continuous transdermal 17 beta-estradiol replacement therapy (0.05 mg/day once a week) with placebo on systemic hemodynamics and blood pressure in postmenopausal women. Twenty-nine postmenopausal women (47-62 years) free of hormone replacement therapy were randomized in two groups; group 1 received estradiol patches for the first 12 weeks and placebo patches for the second, and group 2 received the same treatments in the reverse order. The effect of combined estradiol plus oral norethisterone acetate (NETA) 1 mg was also evaluated in the subset of women with intact uteri (n = 24). Crossover analysis showed that stroke volume and cardiac output were significantly higher (P < 0.05) and blood pressure was significantly lower (P < 0.05) with estradiol, irrespective of the order in which the treatments were administered. Although correlations between plasma estradiol levels during active treatment and hemodynamic changes were not significant, hemodynamic changes were significantly greater above 63 pg/ml than below this level (P < 0.05). Oral norethisterone acetate administration either during transdermal placebo or estradiol arms tended to modify systemic hemodynamics in the same direction than estradiol but the changes did not attained statistical significance. In summary compared with placebo, transdermal 17 beta-estradiol, replacement to postmenopausal women, increased cardiac output and decreased blood pressure. Although the average magnitude of changes was small, the results suggest that plasma estradiol levels could be a source of individual variability in the hemodynamic response. Oral NETA administration tended to enhance rather than reverse the estradiol-induced changes.