Oral contraceptives and thrombotic disease: risk of venous thromboembolism

Studies conducted in the first three decades after discovery of a link between venous thromboembolism and oral contraceptive users showed a relative risk of first thrombosis during oral contraceptive use of 2.9 (95% CI 0.5-17). In recent studies in which the sub-50 micrograms ethinyl estrodiol containing pills were investigated comparing current users with non-users, the RR is 3.8 for non-fatal deep VTE and 2.7 for superficial VTE, deep VTE and pulmonary embolism (PE) together and 2.1 for fatal VT and PE together. The association is attributed to the estrogenic component and not related to duration of pill use. The risk disappears once the pill has been stopped, and it is not elevated among past users. Smoking does not appear to be risk factor for VTE; obesity and varicose veins are, at the most, weak risk factors. Since a causal relationship between OC use and VTE is tempting, clues for unraveling the mechanism were sought in the hemostatic system. Studies of the coagulation system found changes in the activation of coagulation and fibrinolytic compartments, but within the normal range. An epidemiologic study showed that the risk of VTE among women using OCs is 30-fold increased by the presence of a mutation of factor V, called Factor V Leiden (5% prevalence in the Caucasian population). Selective screening for the mutated factor V should be limited to women with a personal or family history of VTE. Four epidemiologic studies showed a two-fold increase in risk of VTE with the use of OCs containing third-generation progestins (gestodene and desogestrel), relative to second-generations products (levonorgestrel). Biases cannot devaluate the conclusion that the increased risk of VTE in especially first-time and younger users of third-generation OCs is highly likely. The clinical consequence is therefore that second-generation OCs are the first choice in prescription to first-time users.

Predicting optimal cervical mucus for infertility diagnosis

OBJECTIVE

We studied the relationship between cervical mucus evaluations and daily fertility examinations in order to find monitoring techniques that can predict optimal mucus one day before it occurs.

METHODS

Twenty-three healthy young female volunteers were followed during one spontaneous cycle with serial measurements of serum estradiol, progesterone, LH and FSH, urinary LH, and transvaginal ultrasound measurements of endometrial thickness and follicles. Data were related to cervical mucus scores.

RESULTS

All cycles were ovulatory with optimal mucus, but in 14 optimal mucus was present for only one day. Echographic measurement of the leading follicle (mean diameter > or = 18 mm) could predict the day of optimal mucus in 78% and estradiol (> 700 pmol/l) in 83% of the cases. These two measurements combined predicted optimal mucus in 100% of the investigated women one day in advance.

CONCLUSION

Optimal cervical mucus parameters can be predicted one day in advance by serial measurements of serum estradiol and follicular diameters.

Factor V Leiden: should we screen oral contraceptive users and pregnant women?

The factor V Leiden mutation is the most common genetic risk factor for deep vein thrombosis: it is present in about 5% of the white population. The risk of deep vein thrombosis among women who use oral contraceptives is greatly increased by the presence of the mutation. The same seems to be true of the risk of postpartum thrombosis. Several authors have called for all women to be screened before prescription of oral contraceptives and during pregnancy. Such a policy might deny effective contraception to a substantial number of women while preventing only a small number of deaths due to pulmonary emboli. Moreover, in pregnancy the ensuing use of oral anticoagulation prophylaxis might carry a penalty of fatal bleeding that is equal to or exceeds the risk of death due to postpartum thrombosis. It might pay, however, to take a personal and family history of deep vein thrombosis when prescribing oral contraceptives or at a first antenatal visit to detect women from families with a tendency to multiple thrombosis.

Immunohistochemical and ultrastructural localization of prostaglandin H synthase in the preimplantation mouse embryo

The immunohistochemical and ultrastructural localization of prostaglandin H synthase (PGH synthase) was studied in the Albino Swiss CF-1 mouse at different stages of embryonic development (two-cell stage, four-eight cell stage, morula and blastocyst). Flushed embryos and sections of uteri and oviducts containing embryos were treated with a mouse IgG monoclonal anti-PGH synthase antibody. The second antibody (rabbit anti-mouse) was conjugated with peroxidase or fluorescein isothiocyanate for light microscopy, fluorescence microscopy and confocal scanning. For reflection contrast microscopy and transmission electron microscopy a second antibody, goat anti-mouse, was conjugated with ultrasmall gold particles. Controls without anti-PGH synthase were used concurrently. All embryos demonstrated PGH synthase reactivity. Immunostaining appeared to be more intense at the two-cell stage, four-eight cell stage embryos and morulae than in blastocysts. Further examination indicated an intracytoplasmic location for PGH synthase, which was confirmed by stereoscopic photographs made during confocal scanning microscopy and by the immunostaining patterns observed with reflection contrast microscopy and transmission electron microscopy. Transmission electron microscopy immunostaining patterns support the localization of PGH synthase in the endoplasmic reticulum. This is the first demonstration of the ultrastructural localization of PGH synthase in the mouse embryo. Its presence before the apposition with the endometrial epithelium supports the hypothesis that arachidonic acid metabolism via the PGH synthase pathway may be crucial for implantation.

Prostanoid excretion in incipient singleton and twin pregnancies

OBJECTIVE

Our purpose was to examine the urinary excretion of metabolites of prostacyclin, 6-keto-prostaglandin F(1 alpha) and 2,3-dinor-6-keto-prostaglandin F(1 alpha), and thromboxane A2, thromboxane B2 and 2,3-dinor-thromboxane B2, in early twin and singleton pregnancies resulting from in vitro fertilization-embryo transfer.

STUDY DESIGN

Overnight urine samples were obtained from 23 women at regular intervals for 20 weeks after embryo transfer. Prostanoids were measured by high-pressure liquid chromatography-radioimmunoassay.

RESULTS

All prostanoids, most markedly 6-keto-prostaglandin F(1 alpha) and 2,3-dinor-6-keto-prostaglandin F(1 alpha), increased in both singleton and twin pregnancies. This resulted in an increased ratio of prostacyclin over thromboxane A2 both in the dinor compounds (from 1.3 to 2.8) and the total metabolites (from 1.7 to 3.5). No marked differences were observed between twin and singleton pregnancies.

CONCLUSIONS

Twin and singleton pregnancies show a similar increase in the prostacyclin to thromboxane A2 ratio in the first half of pregnancy.

Effect of the postcoital test on the sexual relationship of infertile couples: a randomized controlled trial

OBJECTIVE

To investigate the impact of the postcoital test (PCT) on the sexual relationship and functioning of infertile couples.

DESIGN

Randomized controlled study.

SETTING

University hospital.

PATIENTS

New infertility patients were randomized to an infertility work-up with (PCT group) or without (non-PCT group) postcoital test as integral part of the investigation.

INTERVENTION

Performance of the PCT.

MAIN OUTCOME MEASURE

Both partners completed a questionnaire on their sexual relationship and functioning at the initial visit and after 3 months.

RESULTS

Of 500 consecutive new couples, 304 fulfilled inclusion criteria and 290 consented to participate (PCT group: 152; non-PCT group: 138). Answers to both the first and second questionnaire were obtained from 84 couples (PCT: 43; non-PCT: 41). After 3 months, couples in the PCT group were at least as satisfied with their sexual relationship as couples in the non-PCT group with little difference having occurred in the 3 months of investigation.

CONCLUSION

Overall, the influence of the PCT on the sexual relationship of infertile couples is more positive than negative.

Evaluation of the postcoital test for assessment of 'cervical factor' infertility

OBJECTIVE

To evaluate the test properties of the postcoital test (PCT).

STUDY DESIGN

Retrospective analysis of prospectively collected data on a cohort of infertile couples with complete follow up.

SETTING

Fertility clinic of a Dutch university hospital.

SUBJECTS

A continuous series of 224 couples of whom 24 were excluded for reasons of anovulation, coital problems, proven sterility or incomplete follow-up.

ANALYSIS

Cumulative pregnancy rates in relation to PCT results with and without treatment for 'cervical factor' infertility.

RESULTS

The predictive values of normal and abnormal PCTs were 0.54 and 0.58 overall and 0.74 and 0.47 if only untreated women were considered. Sensitivity and specificity were, respectively, 0.47 and 0.65 for all women and 0.54 and 0.68 for untreated women only. Likelihood ratios for normal and abnormal PCTs were 0.83 and 1.32 overall and 0.67 and 1.72 in untreated women.

CONCLUSION

The PCT has poor predictive power. This and the psychological impact on subfertile couples attest to the need for more rigorous study designs in evaluating this test.

Enhancement by factor V Leiden mutation of risk of deep-vein thrombosis associated with oral contraceptives containing a third-generation progestagen

Recent concern about the safety of combined oral contraceptives (OCs) with third-generation progestagens prompted an examination of data from a population-based case-control study (Leiden Thrombophilia Study). We compared the risk of deep-vein thrombosis (DVT) during use of the newest OCs, containing a third-generation progestagen, with the risk of "older" products. We also investigated the influence of family history of thrombosis, previous pregnancy, age, and the thrombogenic factor V Leiden mutation. We selected 126 women with DVT and 159 controls aged 15-49 (mean age 34.9) and premenopausal and found, as compared with non-users, the highest age-adjusted relative risks to be that for an OC containing desogestrel and 30 micrograms ethinyloestradiol (relative risk [RR] 8.7, 95% CI 3.9-19.3). We found lower relative risks for all other types of OC, ranging from 2.2 to 3.8. In a direct comparison, users of the desogestrel-containing oral contraceptive had a 2.5-fold higher risk (95% CI 1.2-5.2) than users of all other OC types combined. The relative risk for the desogestrel-containing OC was similar among women with and without a family history--ie, preferential prescription because of family history cannot explain our findings. Nor could the excess risk be explained by previous pregnancy, and it was highest in the youngest age categories, where we would expect most new users. The age-adjusted RR for the desogestrel-containing contraceptive was 9.2 (3.9-21.4) among non-carriers of the factor V Leiden mutation and 6.0 (1.9-19.0) among carriers of the mutation. This latter risk is superimposed on the 8-fold increased risk of venous thrombosis for carriers of the factor V Leiden mutation. The risk of carriers using the desogestrel-containing OC as compared with noncarrier non-users will therefore be increased almost 50-fold. Use of low-dose OCs with a third-generation progestagen carries a higher risk of DVT than the previous generation of OCs. The absolute risk of DVT associated with these OCs seems to be especially high among carriers of the factor V Leiden mutation and among women with a family history of thrombosis. However, the higher risk associated with OC with a third-generation progestagen compared with previous generations was also present in women without factor V Leiden and with no family history.

Prostanoid excretion before in vitro fertilization relates to the likelihood of pregnancy

The objective of this study was to determine the urinary excretion of prostacyclin (PGI2) and thromboxane A2 (TXA2) metabolites during in vitro fertilization (IVF) in relation to the clinical outcome of IVF. Urine was obtained overnight every 3 to 4 days from 24 women during IVF cycles. TXB2, 6-keto-PGF1 alpha and their 2,3-dinor derivatives were measured by high-pressure liquid chromatography with radioimmunoassay. The patients were women with (n = 16, 119 samples) and without (n = 8, 53 samples) a clinical IVF pregnancy. Concentrations of 2,3-dinor-TXB2 and 2,3-dinor-6-keto-PGF1 alpha were lower before embryo transfer in women who achieved a pregnancy than in those who did not conceive (p < 0.05). Contrary to women who did not conceive, women who achieved pregnancy had an increase in 6-keto-PGF1 alpha excretion after embryo transfer (p = 0.04). In women who did not conceive, levels of 2,3-dinor-TXB2 were higher before embryo transfer than after transfer (p = 0.04) and than levels in women who did conceive (p = 0.01). We concluded that differences in urinary prostanoid metabolite excretion before embryo transfer appear to relate to the likelihood of pregnancy, but the nature of this relationship remains elusive.

[Variations in fertility studies in The Netherlands]

OBJECTIVE

To determine how a standard infertility investigation is conducted and to determine the use of fertility tests used in such investigations in relation to WHO guidelines.

DESIGN

Questionnaire survey.

SETTING

Dutch medical schools.

METHOD

A questionnaire survey among the heads of all 8 university and 20 non-university teaching departments of obstetrics and gynaecology or their fertility units was conducted. One non-university department failed to respond.

RESULTS

The examinations recommended by the WHO (general physical examination, andrological and gynaecological examination, semen analysis, ovulation detection, tubal patency testing) in general were carried out, but general physical examination of the male as a rule was only carried out if indicated. Popular routine examinations not recommended by the WHO were the postcoital test and hysterosalpingography. Regarding the postcoital test, there was variation in the time interval after coitus and the standards for spermatozoal motility.

CONCLUSION

Standard fertility investigations are usually based on empiricism and tradition, including the testing recommended by the WHO.

Lesbian mothers who conceived after donor insemination: a follow-up study

This study investigated the development of family relationships in lesbian families who conceived after donor insemination (DI). The main characteristics of this unknown family structure were analysed. An anonymous donor was used to conceive, the family unit consisted of two mothers and a father was non-existent, and both women had a homosexual orientation. A total of 50 lesbian couples who conceived after DI with children aged between 1 and 2 years participated in this study, using a standardized interview created for this study. After the birth of their child, 56% of the lesbian mothers (n = 100) would have wanted the identity of the donor to be registered, while 10% would have done so at the time of the insemination. Opinions differed in 12 of the 50 couples: the biological mother was in favour of identity registration while the social mother was not. Both women considered themselves a parent of the child with equally shared responsibilities. Mothers were open about the special features of their family structure with children and within their immediate social network. Only 30% disclosed their lesbian identity in a broader social environment. The features of these newly created families may influence the psychological development of the children and therefore make long-term follow-up studies indispensable.

European postcoital tests: opinions and practice

OBJECTIVE

To assess differences in opinion and practice with regard to the postcoital test in Europe.

DESIGN

Multilingual questionnaire survey among heads of departments of obstetrics and gynaecology with large fertility clinics in 16 European countries.

SUBJECTS

Of 203 heads of departments, each responsible for 882 infertility cases per year (95% CI 657-1107) 145 (71%) responded. INFORMATION SOUGHT: Use of the postcoital test: its timing in relation to cycle and coitus, methodology used for the test, cut-off level of normality and treatments applied for abnormal test results.

RESULTS

The postcoital test is used in 92% (and routinely in 68%) of departments. There are large differences in timing of the test in relation to menstrual cycle and coitus, in microscopic magnification used, and in cut-off levels of normality. More than 10 different treatments are applied for abnormal test results.

CONCLUSION

Guidelines of the World Health Organisation are not followed and divergence in practice and opinion is wide enough to question whether infertile couples are better off with than without the test.

Consistency and variation in fertility investigations in Europe

A questionnaire survey among the teaching departments of obstetrics and gynaecology in Western Europe (response rate 71%) revealed only weak adherence to the World Health Organization recommendations for the standard investigation of the infertile couple. Both general and specific examinations were applied more frequently in the female than in the male partner. Although semen analysis and the ascertainment of ovulation were standard in virtually all departments, the criteria for normal semen and the methods used for the detection of ovulation varied greatly among both departments and countries. There were also large differences among countries in the preferred standard method for testing tubal patency. The data suggest that fertility investigations are based more on tradition and personal preferences than on the demonstrated utility of its components.

Oral contraceptives and venous thromboembolism: a quantitative discussion of the uncertainties

OBJECTIVES

The majority of post-thrombotic women are barred from using oral contraceptives. We evaluated this policy for its clinical relevance.

DESIGN

A meta-analysis of controlled studies between 1960 and 1993.

SETTING

A Medline computer search, from 1966 to 1993, in multiple languages, with the following index terms: thrombosis, thrombopheblitis, vein, venous, pulmonary embolism, contraceptives, oestrogen, oral.

STUDY SELECTION

A total of 588 articles or abstracts were reviewed for controlled studies, in which an index group was compared with a control group. Included were one randomized trial, six follow-up studies and eight case-control studies.

MAIN OUTCOME MEASURES

Summary thrombosis risk for oral contraceptive users, number needed to discontinue oral contraceptives to prevent one (recurrent) thrombosis, comparison of additional unwanted pregnancies and postpartum thrombosis between alternative birth-control methods.

RESULTS

The studies proved highly heterogeneous with regard to size and direction of the risk estimate. The summary relative risk of first thrombosis during oral contraceptive use was 2.9 (95% CI, 0.5-17). Since the risk of thrombosis recurrence is not well known, we estimated alternatives, making various hypothetical assumptions, wherein women would continue to take oral contraceptives after a first episode of thrombosis, or stop and switch to use of an intra-uterine device, condom or the progestogen-only pill. Depending on the assumptions with regard to recurrence risk and the existence of possible subgroups with genetic coagulation defects, the cost-benefit ratio of advising against the use of oral contraceptives after a first thrombosis varied tremendously.

CONCLUSIONS

Our analysis shows that we lack the necessary data for recurrence risk of venous thrombosis during continuing use of oral contraceptives, or after switching to other modes of contraception. This reflects the clinical uncertainties that result in highly contradictory advice to young women who have experienced a first thrombosis. Only follow-up studies on recurrence risk will settle the issue.

When is the post-coital test normal? A critical appraisal

A systematic review was conducted of published studies, which related post-coital test (PCT) results to pregnancy, to evaluate the predictive power of the test and determine a definition of abnormality that yielded the best test properties. Well defined test results and valid outcome data for women attending fertility clinics were present in 11 out of 53 published reports relating to a total of 3093 women. The predictive values of normal and abnormal PCT were 0.37-0.92 and 0.58-0.85 respectively. Sensitivity was 0.10-0.90 and specificity 0.30-0.97. Likelihood ratios for normal and abnormal PCT were 0.77 and 1.85 respectively. When criteria for normality were set at a lower number of motile spermatozoa per field, sensitivity decreased with an increase in specificity and likelihood ratio for an abnormal test result. The discriminating ability of the PCT is poor, and altering definitions of normality hardly enhances its predictive power. As long as the value of the PCT for the assessment and treatment of so-called 'cervical factor infertility' remains unclear, a cut-off point with high specificity and a high likelihood ratio for an abnormal test result is recommended. Hence, an abnormal PCT is best defined as less than one motile spermatozoon per high power field.

Follow-up of 30 pregnancies after embryo cryopreservation

OBJECTIVE

In an observational follow-up study, the pregnancy outcome of the first 30 women who conceived after transfer of cryopreserved embryos was evaluated.

STUDY DESIGN

The main outcome measures were duration and complications of pregnancy, mode of delivery, complications during and after childbirth, birthweight, Apgar score, and congenital anomalies.

RESULTS

Twenty-six pregnancies ended in birth of one (n = 22) or more (n = 4) infants with a cesarean section rate of 23%. Of the singleton pregnancies 77% were uncomplicated, but there was a high incidence of breech presentation (14%). Infant birthweight tended to be above average with 45% of singletons weighing more than the 75th centile of weight for gestation. There were no major congenital deformations.

CONCLUSION

The results of our embryo cryopreservation program are encouraging, but sustained follow-up of such pregnancies and infants is needed.

A case of 16-ene-synthetase deficiency in male pseudohermaphroditism due to combined 17 alpha-hydroxylase/17,20-lyase deficiency

A 17-year-old phenotypic female with primary hypergonadotropic amenorrhea, absence of secondary sexual development, hypertension and 46 XY karyotype is presented. Hormonal analysis revealed very low levels of testosterone, dehydroepiandrosterone, androstenedione, estrogens, cortisol and high levels of ACTH, progesterone, deoxycorticosterone and corticosterone. Enzyme studies of the testicular tissue after bilateral gonadectomy showed absence of 17 alpha-hydroxylase and 17,20-lyase activity as well as 16-ene-synthetase activity. This enzyme catalyzes the reaction from pregnenolone to 5,16-androstadien-3 beta-ol, a sex pheromone precursor. The other enzyme systems leading from pregnenolone to testosterone were intact. This is the first report of male pseudohermaphroiditism in which the combination of 17 alpha-hydroxylase, 17,20-lyase and 16-ene-synthetase deficiency is described, indicating that all these activities might be associated with the same protein.

Prostanoid levels in in vitro fertilization culture medium are not related to the likelihood of implantation

OBJECTIVE

To determine prostanoid levels (prostaglandin E2, prostaglandin F2 alpha, 6-keto-prostaglandin F1 alpha, and thromboxane B2 [TXB2]) in embryo culture medium containing inactivated maternal serum and their correlation with the clinical outcome of IVF-ET.

DESIGN

Prostanoid levels were measured in blank control medium and in medium containing an embryo or nonfertilized oocyte with a high-pressure liquid chromatography (HPLC-RIA) method. Comparisons of HPLC-RIA, Seppak C18-RIA, and RIA directly in the medium demonstrated identical results for TXB2, allowing the use of direct RIA in the large investigation of 129 media.

SETTING

Leiden University Hospital, The Netherlands.

PATIENTS

Patients with (n = 12) and without (n = 15) an ongoing pregnancy after IVF-ET.

MAIN OUTCOME MEASURES

Prostanoid levels in embryo culture medium and relationship between prostanoid levels and successful implantation.

RESULTS

Thromboxane B2 is the only prostanoid consistently found in these media. In both groups there was no difference in TXB2 levels between control media, media containing a nonfertilized oocyte, and media containing an embryo. There was no difference in TXB2 levels between media that had harbored the beginning of a successful pregnancy and those that had not produced a pregnancy.

CONCLUSION

Thromboxane B2 in the embryo culture medium originates from maternal serum and bears no relationship with the likelihood of fertilization and implantation.

The influence of indomethacin on the hatching of mouse blastocysts

In order to investigate the effect of indomethacin for inhibition of the cyclooxygenase pathway on the hatching process of mouse blastocysts, 508 mouse blastocysts were cultured in modified HAM F10 medium containing 0, 8, 79 or 788 microM indomethacin, added after 24 h of incubation. Hatching was scored after 72 h of incubation. In another series of experiments, indomethacin was added only after blastulation had occurred. Indomethacin in doses of 8 microM and 79 microM, added after 24 h of incubation or after blastulation had occurred, did not influence successful hatching. A dose of 788 microM indomethacin interfered with hatching, but this dose appeared to be toxic for the embryo.