A prospective longitudinal population-based study of clinical miscarriage in an urban Swedish population

OBJECTIVE

To describe the incidence of clinical miscarriage and to investigate the factors influencing the occurrence of clinical miscarriage.

DESIGN

Prospective study with both cross-sectional and longitudinal comparisons.

SETTING

City of Göteborg, Sweden.

POPULATION

Population-based study in cohorts of 19-year-old women followed longitudinally.

MAIN OUTCOME MEASURES

Incidence of miscarriage and pregnancy outcome.

MATERIAL AND METHODS

A postal questionnaire was sent to women born in 1962 and resident in the city of Göteborg in 1981 (n = 656) regarding pregnancy outcome, clinical miscarriage and other reproductive health factors. Responders in 1981 were contacted again and requested to answer a similar questionnaire every fifth year up to 2001. The same process was repeated in 1991 with women born in 1972 (n = 780) with follow up of these responders in 1996 and 2001. A third cohort of 19-year-old women born in 1982 (n = 666) was interviewed in 2001. The self-reported pregnancy data were verified from hospital files.

RESULTS

Complete data were available for 341 women born in 1962 and assessed up to the age of 39 years (ever pregnant, n = 320, 94%). There were in total 887 pregnancies (live birth, n = 590, 67%; miscarriage, n = 108, 12%; legal abortion, n = 173, 20% and ectopic pregnancy, n = 16, 2%). Of the 320 'ever pregnant' women, 80 women (25%) had experienced a miscarriage. 76.3% had experienced one miscarriage, 16.3% had two miscarriages and 7.4% had three or more miscarriages. The clinical miscarriage rates in women at different ages were as follows: 20-24 years 13.5%, 25-29 years 12.3%, 30-34 years 10.3% and 35-39 years 17.5%. The corresponding miscarriage rate in the 1972 cohort followed from 19 to 29 years of age was 11%, and in the 1982 cohort assessed at 19 years of age, the miscarriage rate was 9%. No risk factor for miscarriage could be reliably identified.

CONCLUSIONS

Clinical miscarriage constituted 12% of all pregnancies, and one in four women who had been pregnant up to 39 years of age had experienced a miscarriage. Three or more miscarriages were experienced by 7.4%. The occurrence of a miscarriage was not influenced by the order of the pregnancy.

Amenorrhoea in newly spinal cord injured women: an effect of hyperprolactinaemia?

STUDY DESIGN

Prospective, single centre study.

OBJECTIVES

Previous studies have suggested a relationship between stress reaction and elevated levels of prolactine. The aim of the present study was to investigate if there was a relationship between s-prolactine and menstrual cycle status following spinal cord injury (SCI).

SETTING

Spinal Cord Injury Unit, Göteborg, Sweden.

METHODS

S-prolactine and menstrual cycle status were investigated in 16 consecutive women with SCI, treated at the SCI Unit, Sahlgrens University Hospital, Göteborg, Sweden. Level of injury ranged from C1 to L5, ASIA A-D. Mean age at injury was 45 years (range 20-79).

RESULTS

S-Prolactine showed a mean value of 741 mIU/l (standard deviation (s.d.): 625; 95% confidence interval (CI): 435-1788 mIU/l, reference value <400 mIU/l). When dividing the group according to fertility status we found hyperprolactinaemia in the women who were in childbearing age (n=9): mean value 1050 mIU/l (s.d.: 678; 95% CI: 607-1493 mIU/ml), whereas it was normal in the group in menopause (n=7): mean value 343 mIU/l (s.d.: 185, 95% CI: 206-480 mIU/l) (P<0.01 when comparing groups). The group that developed amenorrhoea showed the highest values of s-prolactine. All values but one was normalised 3-6 months later.

CONCLUSION

Amenorrhoea following SCI is correlated to level of s-prolactine. We found no correlation between level of s-prolactine and level or degree of injury.

Birth of a healthy infant after in vitro oocyte maturation and ICSI in a woman with diminished ovarian response: Case report

In vitro maturation of oocytes (IVM) has been developed as a treatment option for subjects with good prognosis in assisted reproduction. We present successful IVM treatment in connection with a woman from whom low numbers of embryos were obtained after repeated failed conventional IVF cycles. A 35 year old woman, after 5 years infertility and two intrauterine insemination and three conventional IVF cycles, underwent first an IVM cycle with low dose FSH stimulation, and after failure, another natural IVM cycle. Three oocytes were obtained. After 36 h of IVM the oocytes had reached metaphase II stage, and fertilization using ICSI resulted in one 4-cell stage embryo, which was transferred 2 days later. The result was an uneventful pregnancy and birth of a healthy female infant weighing 4150 g. IVM may be an option for women from whom only low numbers of oocytes are obtained after gonadotrophin stimulation.

Recombinant LH is equally effective as recombinant hCG in promoting oocyte maturation in a clinical in-vitro maturation programme: a randomized study

BACKGROUND

Fertilization treatment using oocytes matured in vitro from pre-ovulatory follicles has many potential applications. It minimizes the risk of severe ovarian hyperstimulation and is an alternative for women with polycystic ovary syndrome who may have problems regarding stimulation for IVF. In-vitro maturation (IVM) may prove important for subjects needing fertility preservation, and also provides information about the final stages of oocyte maturation.

METHODS

From a randomized study of 73 women in an IVF programme, 36 subjects with 228 oocytes were allocated for oocyte maturation in culture medium with recombinant hCG, and 37 subjects with 256 oocytes for maturation with recombinant LH. The primary outcome was the rate of nuclear maturation of oocytes to metaphase II. During the same period, 32 women outside the study underwent 38 individually tailored IVM treatments.

RESULTS

The oocyte maturation rate was 54.8% with hCG and 55.9% with LH; fertilization and cleavage rates were not significantly different. Three pregnancies were achieved in the hCG group and one in the LH group. Seven pregnancies (22.6% per embryo transfer) were achieved in the parallel group.

CONCLUSIONS

Recombinant hCG or LH are equally effective in promoting oocyte maturation in a clinical IVM programme.

Expectant management of first-trimester miscarriage in clinical practice

BACKGROUND

The aim of this study was to evaluate treatment efficacy and patient compliance in women with an early miscarriage managed expectantly in routine clinical practice.

METHODS

During 1995-98, 263 consecutive women who sought medical attention for an ongoing or incomplete miscarriage (gestational length <99 days), and who were circulatory stable and had a gestational residue measuring 15-50 mm (anterio-posterior, A-P diameter) on ultrasound examination were invited to participate in this study. Hemoglobin (Hb), C-reactive protein (CRP), human chorionic gonadotrophin (hCG), progesterone and Rh-factor were analyzed and a questionnaire regarding the pregnancy, duration of genital bleeding and number of days of absenteeism was completed on admission and after 1 and 4 weeks.

RESULTS

Expectant management was considered to be complete (vaginal ultrasound, gestational residue <15 mm after 1 week) in 83%. The patients who were managed successfully by expectant management had a smaller gestational residue (p = 0.026) and a lower mean serum progesterone level (p = 0.025) on referral than in the group of women with failed expectant management. A gynecologic infection was diagnosed in seven cases (3%) and five of the infections were in the group of women who underwent dilatation and curettage. No patient required a blood transfusion. The mean number of days of absenteeism was 3.2 days. There were no differences in Hb levels before or after treatment, number of bleeding days or absenteeism between the groups.

CONCLUSIONS

Expectant management of clinically stable patients with symptoms of early miscarriage is safe, efficient and well tolerated.

Immune regulation of corpus luteum function

Immune cells of myeloid and lymphoid lineages constitute a significant cell mass in the corpus luteum. Changes in the distribution and numbers of these cells within the corpus luteum take place during the life span of the corpus luteum. These cells are now recognized to be important both in structural changes of the corpus luteum as well as in the regulation of steroidogenesis. Cytokines are secreted from immune cells and other cells of the corpus luteum and comprise an important component of the intercellular signaling that is regulating tissue remodeling and the endocrine activity of the gland. This review covers recent findings of the participation of immune cells and cytokines in the regulation of the corpus luteum function.

Different assembly properties of cod, bovine, and rat brain microtubules

Assembly properties of cod, bovine, and rat brain microtubules were compared. Estramustine phosphate, heparin, poly-L-aspartic acid, as well as NaCl, inhibited the assembly and disassembled both bovine and rat microtubules by inhibition of the binding between tubulin and MAPs. The assembly of cod brain microtubules was in contrast only marginally affected by these agents, in spite of a release of the MAPs. The results suggest that cod tubulin has a high intrinsic ability to assemble. This was confirmed by studies on phosphocellulose-purified cod tubulin, since the critical concentration for assembly was independent of the presence or absence of MAPs. The results show therefore that cod brain tubulin has, in contrast to bovine and rat brain tubulins, a high propensity to assembly under conditions which normally require the presence of MAPs. Even if cod MAPs, which have an unusual protein composition, were not needed for the assembly of cod microtubules, they were able to induce assembly of bovine brain tubulin. Both cod and bovine MAPs bound to cod microtubules, and bovine MAP1 and MAP2 bound to, and substituted at least the 400 kDa cod protein. This suggests that the tubulin-binding sites and the assembly-stimulatory ability of MAPs are common properties of MAPs from different species, independent of the tubulin assembly propensity.

The effect of estramustine derivatives on microtubule assembly in vitro depends on the charge of the substituent

Estramustine, and derivatives of estramustine with a charged substituent at position 17 on the estrogen moiety, have been investigated for their effects on bovine brain microtubules in vitro. The negatively charged estramustine phosphate has been found previously to be a microtubule-associated protein (MAP)-dependent microtubule inhibitor [Wallin M, Deinum J and Fridén B, FEBS Lett 179: 289-293, 1985]. In the present study the binding of estramustine phosphate to MAP2 and tau was investigated. Both these MAPs were found to have two to three binding sites for estramustine phosphate which is compatible with the reported number of basic amino acid repeats of these MAPs, considered to be the ultimate tubulin binding domains. The Kd for the binding of estramustine phosphate to MAP2 was estimated to be 20 microM at 4 degrees, and for the binding of tau, 200 microM. The rate of dissociation was very low (T1/2 greater than 2 hr), which indicates that the binding of estramustine phosphate may stabilize the protein-drug complex by changing the protein conformation. Two new negatively charged estramustine derivatives, estramustine sulphate and estramustine glucuronide, were found to be similar MAP-dependent microtubule inhibitors. The concentration for 50% inhibition of assembly was 100 microM for the sulphate derivative, the same as found previously for estramustine phosphate, and 250 microM for the more bulky estramustine glucuronide. A positively charged derivative, estramustine sarcosinate, did not inhibit microtubule assembly or alter the composition of the coassembled MAPs. The morphology of the microtubules was, however, affected. The uncharged estramustine bound to both tubulin and MAPs, but no effects were seen on microtubule assembly, the composition of coassembled MAPs or the microtubule morphology. Our results suggest that only negatively charged estramustine derivatives have a MAP-dependent microtubule inhibitory effect. The two new negatively charged derivatives could therefore be valuable tools in the study of tubulin-MAP interactions. The results also confirm that these interactions between tubulin and MAPs are mainly electrostatic.

Dependency of microtubule-associated proteins (MAPs) for tubulin stability and assembly; use of estramustine phosphate in the study of microtubules

Microtubule-associated proteins (MAPs) were separated from tubulin with several different methods. The ability of the isolated MAPs to reinduce assembly of phosphocellulose purified tubulin differed markedly between the different methods. MAPs isolated by addition of 0.35 M NaCl to taxol-stabilized microtubules stimulated tubulin assembly most effectively, while addition of 0.6 M NaCl produced MAPs with a substantially lower ability to stimulate tubulin assembly. The second best preparation was achieved with phosphocellulose chromatographic separation of MAPs with 0.6 M NaCl elution. The addition of estramustine phosphate to microtubules reconstituted of MAPs prepared by 0.35 M NaCl or phosphocellulose chromatography, induced less disassembly than for microtubules assembled from unseparated proteins, and was almost without effect on microtubules reconstituted from MAPs prepared by taxol and 0.6 M NaCl. Estramustine phosphate binds to the tubulin binding part of the MAPs, and the results do therefore indicate that the MAPs are altered by the separation methods. Since the MAPs are regarded as highly stable molecules, one probable alteration could be aggregation of the MAPs, as also indicated by the results. The purified tubulin itself seemed not to be affected by the phosphocellulose purification, since the microtubule proteins were unchanged by the low buffer strenght used during the cromatography. However, the assembly competence after a prolonged incubation of the microtubule proteins at 4 degrees C was dependent on intact bindings between the tubulin and MAPs.

Proteolytic cleavage of high-molecular-weight microtubule-associated proteins by the prostatic estramustine-binding protein

The rat prostatic estramustine-binding protein was found to inhibit assembly of microtubules in a concentration-dependent manner. The inhibition was caused by a proteolytic cleavage of the high-molecular-weight microtubule associated proteins (MAPs), as judged by sodium dodecyl sulfate-gel electrophoresis. A proteolytic fragment with a molecular weight of 199 kDa appeared, which remained bound to the assembled microtubules. Fragments of lower molecular weights (170, 149 kDa) were also found, but they did not bind to the assembled microtubules. Fragments with identical molecular weights were also found after incubation of purified MAP2 with the estramustine-binding protein, indicating that the fragments derive from MAP2. No proteolysis of tubulin, albumin, or casein was found. The estramustine-binding protein was found to be a Zn2+-dependent protease; it was inhibited by EDTA and reactivated by addition of 1 mM Zn2+. Its proteolytic activity was not affected by binding of the antimitotic drug estramustine.

Effects of proteolysis of the extending parts of the high-molecular-weight microtubule-associated proteins on interactions between microtubules

Digestion of assembled microtubules with agarose-bound trypsin was performed to obtain microtubules which lack the extending projections, the non-tubulin-binding part of the high-molecular-weight microtubule-associated proteins. The assembly kinetics and the minimum protein concentration for assembly were the same for these trypsinated microtubules as for normal, untreated microtubules. Furthermore, the digested microtubules gave rise to the same change in turbidity per polymer mass as that found for normal microtubules. However, electron microscopy of pelleted microtubules revealed a closer packing after trypsin treatment. A substantially lower increase in specific viscosity was found upon assembly. At concentrations of above approx. 1.5 mg/ml, the viscosity of trypsin-treated microtubules was almost independent of the protein concentration, in contrast to the turbidity, which still increased. Both microtubules and the trypsin-digested microtubules were easily oriented by shear, although the flow linear dichroism signal for the microtubules after trypsin treatment was only half of that found for perfectly oriented normal microtubules. At higher shear force gradients, digested microtubules aggregated side by side as shown by electron microscopy. This was not found for normal microtubules. Even although the extending parts of the high-molecular-weight proteins are not needed for assembly, they were found to play an important role in microtubule orientation and interactions between microtubules, probably by acting as spacers between microtubules.

Effect of estramustine phosphate on the assembly of trypsin-treated microtubules and microtubules reconstituted from purified tubulin with either tau, MAP2, or the tubulin-binding fragment of MAP2

Estramustine phosphate, an estradiol nitrogen-mustard derivative is a microtubule-associated protein (MAP)-binding microtubule inhibitor, used in the therapy of prostatic carcinoma. It was found to inhibit assembly and to induce disassembly of microtubules reconstituted from phosphocellulose-purified tubulin with either tau, microtubule-associated protein 2, or chymotrypsin-digested microtubule-associated protein 2. Estramustine phosphate also inhibited assembly of trypsin-treated microtubules, completely depleted of high-molecular-weight microtubule-associated proteins, but with their microtubule-binding fragment present. In all cases estramustine phosphate induced disassembly to about 50%, at a concentration of approximately 100 microM, at similar protein concentrations. However, estramustine phosphate did not affect dimethyl sulfoxide-induced assembly of phosphocellulose-purified tubulin. Estramustine phosphate is a reversible inhibitor, as the nonionic detergent Triton X-100 was found to counteract the inhibition in a concentration-dependent manner. The reversibility was nondisruptive, as Triton X-100 itself did not affect microtubule assembly, microtubule protein composition, or morphology. This new reversible MAPs-dependent inhibitor estramustine phosphate affects the tubulin assembly, induced by tau, as well as by the small tubulin-binding part of MAP2 with the same concentration dependency. This indicates that tau and the tubulin-binding part of MAP2, in addition to their assembly promoting functions also have binding site(s) for estramustine phosphate in common.

Interaction of estramustine phosphate with microtubule-associated proteins

We have reported [(1984) Cancer Res., in press] that estramustine phosphate inhibits microtubule assembly and disassembled preformed microtubules. We now present evidence that estramustine phosphate inhibits microtubule assembly by binding to the microtubule-associated proteins. We have found that: additional microtubule-associated proteins relieved the inhibition of assembly by estramustine phosphate; 3H-labelled estramustine phosphate bound predominantly to the microtubule-associated proteins; and the content of the microtubule-associated proteins was reduced in taxol reversed estramustine phosphate-inhibited microtubules.