Augmentation of DNA synthesis in placental and fetal tissues in utero by maternal growth hormone treatment.

The influence of maternal exogenous growth hormone treatment on in utero conceptus development was evaluated in the rat. The periods of response and stimulation of DNA synthesis on embryo/fetal and placental tissues were assessed by subcutaneous injections of ovine growth hormone (oGH) preparations during pregnancy days 11-15, autopsied on day 16; and during pregnancy days 11-20 and 16-20, autopsied on day 21. To determine DNA biosynthesis potential, thymidine (methyl-3H) was administered through the jugular vein 14-16 h prior to sacrifice. DNA content and uptake of radiolabeled thymidine into DNA were analyzed for whole embryos on day 16, and for fetal liver, brain and remaining body tissues on day 21 of pregnancy. Placental tissues from oGH-treated mother and controls were also quantified for DNA content and radiolabeled thymidine uptake. oGH treatment produced a significant increase (p < 0.05) in radiolabeled thymidine uptake into DNAs of different fetal organs compared to saline-treated controls matched for weight and litter number during the latter part of gestation (fetal histogenesis period; pregnancy days 16-20). The stimulatory influence of maternal growth hormone treatment on DNA contents and radiolabled thymidine uptake on placental tissues at this period of gestation was also significantly different from that of the controls. Rat conceptus tissues (embryos and placentas) during the organogenesis period of early gestation (days 11-15) appeared to be unresponsive to such treatment. Thus, these results suggest that maternal growth hormone influences conceptus growth during the latter part of gestation and activation of placental functions may be an important aspect of stimulation of cell proliferation in the rat fetus.

Altered follicular development in clomiphene citrate versus human menopausal gonadotropin-stimulated cycles for in vitro fertilization.

The pattern of periovulatory and luteal phase serum estradiol (E2) and progesterone (P) as well as follicular fluid (FF) E2, P, androgen, gonadotropin, and prolactin concentrations of eight women undergoing clomiphene citrate (CC)/human chorionic gonadotropin (hCG) stimulation and eight women undergoing human menopausal gonadotropin (hMG)/hCG stimulation of follicular development for the purpose of in vitro fertilization were compared. Ovulation was induced with either a 5-day course of CC (100 mg/day beginning on day 5 of the cycle) or an individualized hMG regimen, and laparoscopy was performed 36 hours after hCG administration. The length of the luteal phase was significantly longer (P less than 0.05) in the CC-treated group as compared with the hMG-treated group. The pattern of serum E2 levels differed significantly (P less than 0.01) in that E2 levels were lower in the early and midluteal phase in CC-stimulated cycles; in addition, a delayed second E2 peak was observed in the late luteal phase in these women. Serum P levels, however, were lower in the hMG-stimulated group. Analysis of FF hormone concentrations revealed significantly (P less than 0.05) higher concentrations of E2 and androsterone in the FF of hMG-treated patients. It is concluded that follicular development in CC-stimulated cycles differs markedly from that in hMG-stimulated cycles. These differences may reflect either an altered follicular maturational process or may represent a direct inhibitory effect of CC on follicular steroidogenesis.

The association between granulosa cell aromatase activity and oocyte-corona-cumulus-complex maturity from individual human follicles.

The steroidogenic capability of granulosa cells isolated from 12 preovulatory human follicles was correlated with the stage of maturation of the corresponding oocyte-corona-cumulus-complex ( OCCC ). Individual follicles from human menopausal gonadotropin (hMG) stimulated cycles were aspirated 36 h after administration of hCG. Granulosa cells were cultured for 150 min and corresponding OCCC were evaluated for maturity before fertilization with human sperm. Granulosa cell aromatase activity was measured using 1 beta-3H-testosterone as substrate by quantitating the amount of 3H2O produced. Progesterone production by the granulosa cells was measured as was follicular fluid levels of combined hCG and LH activity and FSH and PRL. Follicular fluid concentrations of combined hCG plus LH activity decreased somewhat while FSH levels increased as OCCC matured. PRL levels did not vary. Granulosa cell progesterone production did not change with maturity of OCCC . However, aromatase activity decreased as OCCC matured with levels from granulosa cells with immature OCCC vs. intermediate and mature OCCC of 260 +/- 148 vs. 129 +/- 53 (SE) pg E2/10(5) cells, respectively (P less than 0.07). Although granulosa cells responded variably to hMG stimulation from individual to individual, and the response was not predictable from peripheral serum estradiol levels, follicles isolated from the same patient had a definite diminution in aromatase activity with OCCC maturation. From these preliminary results, aromatase activity in immediately preovulatory granulosa cells declined as OCCC matured in hMG/hCG stimulated cycles.

The relationship between follicular fluid steroid concentration and successful fertilization of human oocytes in vitro.

Follicular fluids (FF) and their matched oocytes were obtained from 64 follicles of 28 women who failed to conceive after in vitro fertilization ( IVF ) and 33 follicles of 8 women who successfully conceived after the procedure. Ovulation was induced with human menopausal gonadotropin, and follicular aspiration was performed 36 hours after human chorionic gonadotropin administration. The concentration of 17 beta-estradiol, progesterone, testosterone, dihydrotestosterone, and androsterone was correlated with the morphology of the oocyte-corona-cumulus complex ( OCCC ), oocyte fertilization, the rate of cleavage, and the incidence of pregnancy after embryo transfer. In both groups of women, FF progesterone was lowest in follicles containing immature OCCCs . However, follicles aspirated from women who conceived after IVF which contained intermediate and mature OCCCs had significantly higher FF estradiol levels than similar follicles from women who failed to conceive after the procedure. Fertilized oocytes and 4- to 6-cell stage embryos which were obtained from follicles of pregnant women contained significantly higher FF estradiol levels than fertilized oocytes and similar embryos from nonpregnant women. It appears that higher FF estradiol levels correlate well with successful fertilization and an enhanced cleavage rate of oocytes associated with pregnancy following IVF .

Gonadotropin and prolactin levels in follicular fluid of human ova successfully fertilized in vitro.

Follicular fluid (FF) and oocytes were obtained from 94 follicles of 36 women for fertilization in vitro. Ovulation was induced with human menopausal gonadotropin, and follicular aspiration was performed 36 h after an ovulatory injection of hCG. The concentrations of immunoreactive hCG, FSH, and PRL were correlated with the degree of maturation of the oocyte-corona-cumulus complex mass (OCCC), fertilization, rate of cleavage, and the incidence of pregnancy after embryo transfer. Immature OCCC were derived from follicles that contained significantly lower levels of FSH than those from which intermediate and mature OCCC were derived (5.2 +/- 0.6 vs. 11.1 +/- 1.2 mlU/ml; P less than 0.05). FF from oocytes that were successfully fertilized contained higher levels of both hCG and FSH than FF surrounding oocytes that did not fertilize (136.7 +/- 8.7 vs. 108.5 +/- 10.3 mlU/ml hCG; 10.55 +/- 0.6 vs. 5.3 +/- 0.8 mIU FSH, respectively). There was no correlation between early embryonic growth rate and FF concentrations of FSH, hCG, and PRL. Ova reaching the two-cell stage 40 h after fertilization in vitro were associated with the same FF concentrations of FSH, hCG, and PRL as those that cleaved to the four-cell stage. The PRL concentration in FF was significantly higher in mature fertilized ova and in fertilized ova that were associated with a successful pregnancy. It is suggested that the intrafollicular concentration of FSH is associated with the degree of mucification of the OCCC, but FF levels of both FSH and hCG are associated with successful fertilization. High levels of PRL in FF were associated with successful pregnancy and may imply a role of this hormone in oocyte maturation.