Biomedical subjects

R G Forman

Publications and source records attributed to R G Forman.

25 records · Page 2Linked to original sources

PubMed1989

Assessing the early luteal phase in in vitro fertilization cycles: relationships between plasma steroids, endometrial receptors, and endometrial histology.

The corpus luteum-endometrial unit was investigated in in vitro fertilization (IVF) cycles using endocrine, morphologic, and biochemical measurements on the day normally scheduled for embryo transfer (day 16), in 12 stimulated and 4 natural cycles. Advanced endometrial histologic maturity was recorded in 9 of the 12 stimulated cycles. No in-phase endometria were seen when the preovulatory plasma estradiol (E2) was greater than 500 pg/ml or the day 16 plasma progesterone (P) greater than 10 ng/ml in natural or stimulated cycles. Significant negative correlations were noted between both preovulatory E2 and day 16 P and the concentration of cytosolic progesterone receptor (PRc). Advanced endometrial maturity tended to be associated with low concentrations of PRc. Regardless of endometrial maturity, the natural cycle was characterized by low cytosolic E2 receptors (ERc) and high PRc, whereas the concentration of both receptors was usually greatly reduced in stimulated cycles. It is concluded that the advanced endometrial maturation observed in stimulated IVF cycles is a consequence of the production of supraphysiologic levels of sex steroids by the corpus luteum that cause profound modifications of endometrial receptor dynamics.

Clomiphene↗

PubMed1988

An assessment of alternative policies for embryo transfer in an in vitro fertilization-embryo transfer program.

Conventionally, in in vitro fertilization (IVF) programs, all embryos obtained up to three are freshly transferred in the IVF cycle and supernumerary embryos frozen if cryopreservation facilities exist. This study was concerned with assessing alternative policies for embryo transfer (ET). When three or fewer embryos were obtained in the IVF cycle, fresh embryo transfer was either excluded (group I, n = 69) or only one embryo was immediately transferred (group II, n = 46), the remainder being transferred after freezing and thawing. The pregnancy rate in these two policies was compared to that in a control group of patients (group III, n = 115) in whom all the embryos were transferred in the IVF cycle. The ongoing pregnancy rate was similar in all three groups. No multiple pregnancies occurred in groups I and II compared with one in the controls. The consequences of these policies for pregnancy rates and the incidence of multiple gestation are discussed. It is concluded that the deliberate limitation of fresh ET to a maximum of one embryo followed by one or more cycles of thawed frozen ET is not detrimental to the pregnancy rate and is less likely to be associated with multiple gestations. Conversely, this policy increases the workload of the laboratory staff and raises certain ethical questions.

Chorionic Gonadotropin↗

PubMed1988

Management of triplet pregnancy.

Based on the outcome of 21 triplet pregnancies from Antoine Béclère Hospital, early diagnosis in the major requirement for improving rates of fetal survival in multiple pregnancies. The outcome was better in mothers with spontaneous ovulation than in those with induced ovulations. Elective cesarean section is proposed.

Betamethasone↗

PubMed1988

Improvements in ovarian stimulation for in vitro fertilization.

What are the major improvements in stimulation over recent years? The stimulated cycle has completely superseded the natural cycle since this is the only method of obtaining several embryos. In conventional stimulation, despite an enormous body of literature, no single treatment modality has emerged as superior to other forms of therapy. Undoubtedly it is the experience and habits of individual IVF teams that determine the success of one or another method. Therefore programmed stimulation is an improvement in that it introduces the factors of convenience and simplicity while retaining the clinical efficacy of stimulation by conventional treatment. The analogues of LHRH are still in an early phase of development, but they appear to be associated with a low cancellation rate even in previous poor-responders. Furthermore, preliminary results seem to indicate that this is the first development since the widespread adoption of follicular stimulation, which is associated with an increased pregnancy rate. We are currently involved in trying to associate programmed stimulation and analogue treatment in a bid to combine the advantages of both therapies. Finally, embryo cryopreservation must be mentioned. There is no point in refining our stimulation protocols to obtain many embryos if those surplus to immediate requirement are disposed of. Cryopreservation offers the means of maximizing the pregnancy potential of a single IVF cycle while reducing the possibility of multiple pregnancy.

Embryo, Mammalian↗

PubMed1987

The effect of dydrogesterone supplementation in an IVF programme.

Various treatments are given during the luteal phase by most IVF programmes, without any proof of their efficacy. We have performed a double-blind, randomized study with dydrogesterone (125 transfers) against placebo (133 transfers). The pregnancy rate was 21.6 versus 15.0% per transfer cycle with dydrogesterone or placebo, respectively. There was no significant difference between these figures, but taking into account the usual success rate in IVF programmes (15-20%) a difference of 5% would be significant only with two groups of 1500 subjects. This paper discusses the question of how we can come to a definite conclusion on the efficacy of hormonal supplementation during the luteal phase.

Adult↗

PubMed1987

One year's experience with programmed oocyte retrieval for IVF.

We have previously described a simplified form of ovulation stimulation for IVF in which the day of presumed oocyte retrieval is determined several weeks in advance. This paper retrospectively analyses this technique in 296 unselected patients over a one year period to assess if the method is suitable for routine use in an IVF programme. Oocyte retrieval was performed on the predetermined day in 70% of patients commencing stimulation. In the remainder, the presumptive day of oocyte retrieval was modified, or the cycle was cancelled. Compared with 356 patients undergoing a comparable classically monitored IVF stimulation during the same period, there was no significant difference in the cancellation rate of cycles prior to oocyte recovery, in the numbers of oocytes or embryos obtained or in the pregnancy rate between the two populations. It is concluded that programmed oocyte retrieval does not have a deleterious effect on the success rate of IVF compared with classical clomiphene citrate/HMG stimulation and it considerably facilitates the administration of an IVF programme.

Clomiphene↗

PubMed1987

The effect of endogenous progesterone on basal body temperature in stimulated ovarian cycles.

Whilst it is well recognized that progesterone is involved in the elevation of body temperature following ovulation, the mechanism for this process has not been determined. In this study 87 patients undergoing in-vitro fertilization recorded their basal body temperature during one treatment cycle. Exogenous gonadotrophin therapy administered to induce multiple folliculogenesis considerably elevated periovulatory oestrogen levels and early luteal phase progesterone. Body temperature rapidly rose to plateau 48 h after follicular aspiration in all patients. The amplitude of the temperature rise was independent of the progesterone concentration and the type of hormonal stimulation. There was no correlation between the degree of elevation of progesterone and the amplitude of the rise in body temperature over the first 4 days of the luteal phase. It is postulated that serum progesterone levels do not directly control body temperature, but that an oestrogen-progesterone synergism may be involved.

Body Temperature↗