Use Of Assisted Reproduction Research Articles

Pharmacokinetics of the progesterone-containing vaginal tablet and its use in assisted reproduction

Natural progesterone, which is devoid of androgenic activity, is widely used in assisted reproduction for luteal and pregnancy support. The vaginal route has become the most established way to deliver natural progesterone because it is easily administered, avoids liver first-pass metabolism, and has no systemic side-effects. The vagina has a large potential for absorption, and through the ‘uterine first-pass effect’ vaginal administration results in higher uterine progesterone concentrations. We have investigated the pharmacokinetics of natural progesterone in the form of a vaginal tablet. A single dose of 100 mg resulted in a mean C max of 31.53 ± 9.15 nmol/l with a T max of 6.92 ± 3.12 h. The terminal half-life was 16.39 ± 5.25 h. The pharmacokinetic data are discussed in relation to dose, age, and estrogen priming. Single-dose pharmacokinetics of 100 mg of progesterone vaginal tablets and gelatin capsules were evaluated over 24 h. Results indicated a similar mean T max of 6.92 ± 3.12 and 6.23 ± 6.57 h, respectively. However, a significantly higher C max was achieved by the vaginal tablet (31.95 ± 9.15 and 23.85 ± 9.57 nmol/l, respectively, P < 0.05). Continuous use of vaginal progesterone did not influence the hormonal, liver, or lipid profiles evaluated. There was no case of endometrial hyperplasia. The vaginal tablet was found to be well-tolerated, safe, and easily administered. In conclusion, progesterone-containing vaginal tablets have good pharmacokinetic properties and should be used for progesterone supplementation in IVF.

Safety factors important with drug use in assisted reproduction

Safety factors important with drug use in assisted reproduction

Artificial Stimulation of Cryopreserved Human Spermatozoa by Sodium Nitroprusside, 2-Chloroadenosine, and 2-Deoxyadenosine

We analyzed the effects of sodium nitroprusside (SNP), 2-chloroadenosine (2-CLA), and 2-deoxyadenosine (2-DA) on sperm motility and motion characteristics of cryopreserved human spermatozoa. Thawed semen samples from healthy donors (n = 10) were incubated with the stimulants for 0, 30, 60, 120, and 180 min. The final concentrations used were SNP 25, 50, and 100 nM; 2-CLA 12.5, 25, and 50 microM, and 2-DA 0.5, 1, and 2.5 mM. Sperm motility and changes in motion characteristics were measured on a computer-assisted semen analyzer. Compared with control (0 min, no stimulant), a significant improvement in percentage motility was generally seen with all three stimulants even at 180 min. The sperm motility improved at concentrations of 50 and 100 nM for SNP (except at 120 min), 25 and 50 microM for 2-CLA, and at all concentrations of 2-DA. Other sperm motion characteristics increased to varying extent with the stimulants. Of the three stimulants, all concentrations of 2-DA resulted in significant increases in curvilinear velocity, average path velocity, and amplitude of lateral head displacement at 60 min of incubation. All three stimulants significantly increased percentage motility for extended intervals of time. 2-DA also improved sperm motion characteristics, though these changes were less uniform with 2-CLA. Motility stimulation by these chemicals may be beneficial in the treatment of cryopreserved and oligozoospermic sperm specimens for use in assisted reproduction.

Sperm kinematics of cryopreserved normozoospermic specimens after artificial stimulation

Objectives Cryopreservation of semen is associated with reduced motility after thawing, resulting in a decreased pregnancy rate. Artificial stimulation of motility has been used in fresh semen samples. This study measured the effect of motility stimulants on various motion characteristics and other sperm functions using cryopreserved semen. Methods Frozen semen samples from healthy donors were thawed, and motility stimulants were added in vitro and incubated for 60 minutes. The percentages of motile spermatozoa in each specimen and other motion characteristics were measured. In addition, spermatozoon's viability, membrane integrity, and ability to penetrate bovine cervical mucus were studied after addition of stimulants. Results Percentage motility and all other motion characteristics improved after stimulation with pentoxifylline, caffeine, or 2-deoxyadenosine. Linearity did not significantly differ in the control samples after adding any of the stimulants. Viability, membrane integrity, and penetration ability did not improve significantly and were comparable with control values. Conclusions Pentoxifylline, caffeine, and 2-deoxyadenosine can stimulate sperm motility and other motion characteristics. This may be beneficial in the cryopreservation of sperm from normal donors and oligozoospermic patients for use in assisted reproduction.

'The good of the child'

Warnock, chair of Britain's Committee of Inquiry into Human Fertilisation and Embryology, discusses the implications of the "artificial family" for children born through the use of reproductive technologies. She considers both treatment of infertility and the possible use of assisted reproduction to enable persons other than infertile couples, such as single persons and homosexuals, to have children. Warnock has found that emphasis has been placed on the wants and well-being of the adult(s) involved, and that the "good of the child" is a "wide and vague concept, widely invoked, not always plausibly." She is particularly concerned about children born as a result of the delayed implantation of frozen embryos, AID children who are deceived about their origins, and children born of surrogate pregnancies. She recommends that a detailed study of existing "artificial family" children be conducted to aid public policy decisions on assisted reproduction.