Obstetric outcome in donor oocyte pregnancies: a matched-pair analysis

ABSTRACT: BACKGROUND: To investigate the obstetrical and perinatal impact of oocyte donation, a cohort of women who conceived after OD was compared with a matched control group of women who became pregnant through in vitro fertilisation with autologous oocytes (AO). METHODS: A matched-pair analysis has been performed at the Centre for Reproductive Medicine of the UZ Brussel, Dutch speaking Free University of Brussel. A total of 410 pregnancies resulted in birth beyond 20 weeks of gestation occurring over a period of 10 years, including 205 oocyte donation pregnancies and 205 ICSI pregnancies with autologous oocytes (AO). Patients in the OD group were matched on a one-to-one basis with the AO group in terms of age, ethnicity, parity and plurality. Matched groups were compared using paired t-tests for continuous variables and McNemar test for categorical variables. A conditional logistic regression analyses was performed adjusting for paternal age, age of the oocyte donor, number of embryos transferred, and singleton/twin pregnancy. RESULTS: Oocyte donation was associated with an increased risk of pregnancy induced hypertension (PIH) (matched OR: 1.502 CI: 1.024-2.204), and first trimester bleeding (matched OR: 1.493 CI: 1.036-2.15). No differences were observed between the two matched groups with regard to gestational age, mean birth weight and length, head circumference and Apgar scores. CONCLUSIONS: Oocyte donation is associated with an increased risk for PIH and first trimester bleeding independent of the recipients? age, parity and plurality, and independent of the age of the donor or the partner. However, oocyte donation has no impact on the overall perinatal outcome.     

Protein lateral mobility as a reflection of membrane microstructure

The lateral mobility of membrane lipids and proteins is presumed to play an important functional role in biomembranes. Photobleaching studies have shown that many proteins in the plasma membrane have diffusion coefficients at least an order of magnitude lower than those obtained when the same proteins are reconstituted in artificial bilayer membranes. Depending on the protein, it has been shown that either the cytoplasmic domain or the ectodomain is the key determinant of its lateral mobility. Single particle tracking microscopy, which allows the motions of single or small groups of membrane molecules to be followed, promises not only to reveal new features of membrane dynamics, but also to help explain longstanding puzzles presented by the photobleaching studies, particularly the so-called immobile fraction. The combination of the two complementary technologies should measurably enhance our understanding of membrane microstructure.     

Influence of gonadal hormones and social housing conditions on agonistic,copulatory, and related socio-sexual behaviour in the Mongolian gerbil (Meriones unguiculatus)

The Mongolian gerbil is colonial, but its social organization within its colonies is not known. Pair formation has been suggested by breeders and has been observed under semi-natural conditions. Family units remain stable under such conditions. In the solitary-living hamster (Cricetus auratus), agonistic behaviour decreases in male-female encounters during female heat. This report concerns the influence of female and male gonadal hormones on agonistic behaviour in gerbils studied in cagemate and non-cagemate encounters. Further, the occurrence of mating, marking, and drumming was studied in the same situations. No effects were found of either the female or the male endocrine condition on the low amount of agonistic behaviour between cagemates. A reduction in the high amount of agonistic responses in encounters between non-cagemates was indicated. It was related to the castrated-male and induced-oestrous female conditions. Copulatory behaviour was not influenced by social maintenance conditions. Marking and drumming were most frequent in females in oestrous and intact males. The occurences in the females were influenced by the individual's endocrine condition, but not by the opponent's. Intact males in encounters with non-cagemates marked more frequently when the females were in anoestrous. Drumming in the intact males increased in tests with oestrous versus anoestrous females but occurred more frequently in encounters with non-cagemates than in those with cagemates. The behaviour of castrated males was not influenced by the endocrine or by social housing conditions. The limited variation in agonistic behaviour relative to the endocrine conditions may reflect a non-solitary social organization.     

Cleavage inhibition in marine eggs by puromycin and 6-dimethylaminopurine

The possibility is discussed that puromycin may not inhibit cleavage in marine eggs solely by inhibiting protein synthesis. It is suggested that part of the effect of puromycin is through 6-dimethylaminopurine (DMAP) (the purine component of puromycin) a potent cleavage inhibitor which appears to enhance protein synthesis in sea urchin eggs.     

Embryonic fibronectins are up-regulated following peripheral nerve injury in rats

Fibronectin mRNAs that include the alternatively spliced exons EIIIA, EIIIB, and V are prevalent during embryogenesis, and EIIIA and EIIIB reappear during wound healing. Using ribonuclease protection analyses, we found an up-regulation of V120 (containing the α₄β₁ integrin binding site), as well as EIIIA, and EIIIB in fibronectin mRNAs in the crush-injured adult rat sciatic nerve. In situ hybridization using splice variant-specific probes revealed that cells within endoneurial tubes of the injured nerve synthesize these embryonic forms of fibronectin. Our results suggest that embryonic fibronectins synthesized within the nerve contribute to the permissiveness of the peripheral nervous system to axon regrowth and a mechanism by which alternative splicing of the V region in fibronectin mRNA could enhance nervous system regeneration. © 1995 John Wiley & Sons, Inc.