Fulco van der Veen

Polymorphism for a 1.6-Mb deletion of the human Y chromosome persists through balance between recurrent mutation and haploid selection

Many human Y-chromosomal deletions are thought to severely impair reproductive fitness, which precludes their transmission to the next generation and thus ensures their rarity in the population. Here we report a 1.6-Mb deletion that persists over generations and is sufficiently common to be considered a polymorphism. We hypothesized that this deletion might affect spermatogenesis because it removes almost half of the Y chromosomes AZFc region, a gene-rich segment that is critical for sperm production. An association study established that this deletion, called gr/gr, is a significant risk factor for spermatogenic failure. The gr/gr deletion has far lower penetrance with respect to spermatogenic failure than previously characterized Y-chromosomal deletions; it is often transmitted from father to son. By studying the distribution of gr/gr-deleted chromosomes across the branches of the Y chromosomes genealogical tree, we determined that this deletion arose independently at least 14 times in human history. We suggest that the existence of this deletion as a polymorphism reflects a balance between haploid selection, which culls gr/gr-deleted Y chromosomes from the population, and homologous recombination, which continues to generate new gr/gr deletions.

Aspirin plus Heparin or Aspirin Alone in Women with Recurrent Miscarriage

BACKGROUND Aspirin and low-molecular-weight heparin are prescribed for women with unexplained recurrent miscarriage, with the goal of improving the rate of live births, but limited data from randomized, controlled trials are available to support the use of these drugs. METHODS In this randomized trial, we enrolled 364 women between the ages of 18 and 42 years who had a history of unexplained recurrent miscarriage and were attempting to conceive or were less than 6 weeks pregnant. We then randomly assigned them to receive daily 80 mg of aspirin plus open-label subcutaneous nadroparin (at a dose of 2850 IU, starting as soon as a viable pregnancy was demonstrated), 80 mg of aspirin alone, or placebo. The primary outcome measure was the live-birth rate. Secondary outcomes included rates of miscarriage, obstetrical complications, and maternal and fetal adverse events. RESULTS Live-birth rates did not differ significantly among the three study groups. The proportions of women who gave birth to a live infant were 54.5% in the group receiving aspirin plus nadroparin (combination-therapy group), 50.8% in the aspirin-only group, and 57.0% in the placebo group (absolute difference in live-birth rate: combination therapy vs. placebo, -2.6 percentage points; 95% confidence interval [CI], -15.0 to 9.9; aspirin only vs. placebo, -6.2 percentage points; 95% CI, -18.8 to 6.4). Among 299 women who became pregnant, the live-birth rates were 69.1% in the combination-therapy group, 61.6% in the aspirin-only group, and 67.0% in the placebo group (absolute difference in live-birth rate: combination therapy vs. placebo, 2.1 percentage points; 95% CI, -10.8 to 15.0; aspirin alone vs. placebo -5.4 percentage points; 95% CI, -18.6 to 7.8). An increased tendency to bruise and swelling or itching at the injection site occurred significantly more frequently in the combination-therapy group than in the other two study groups. CONCLUSIONS Neither aspirin combined with nadroparin nor aspirin alone improved the live-birth rate, as compared with placebo, among women with unexplained recurrent miscarriage. (Current Controlled Trials number, ISRCTN58496168.)

Risk factors for ectopic pregnancy: a meta-analysis *

OBJECTIVE To review current knowledge on the risk of ectopic pregnancy (EP), with the exception of contraceptive methods. DESIGN Meta-analysis. SETTING Case control and cohort studies published between 1978 and 1994 in English, French, German, or Dutch, retrieved by Medline search, crossover search from the papers obtained, and hand-search on recent medical journals. PATIENTS A total number of 6,718 cases of EP in 27 case control studies and 13,049 exposed women in 9 cohort studies. MAIN OUTCOME MEASURES Detected studies were tested for homogeneity. If homogeneity was not rejected, Mantel-Haenszel common odds ratios (OR) and 95% confidence intervals were calculated. RESULTS Previous EP, previous tubal surgery, documented tubal pathology, and in utero diethylstilbestrol (DES) exposure were found to be associated strongly with the occurrence of EP. Previous genital infections (pelvic inflammatory disease [PID], chlamydia, gonorrhoea), infertility, and a lifetime number of sexual partners > 1 were associated with a mildly increased risk. For gonorrhoea, PID, previous EP, previous tubal surgery, and smoking, a higher common OR was calculated when using pregnant controls compared with using nonpregnant controls. CONCLUSIONS The strong risk in women with a previous EP, previous tubal surgery, documented tubal pathology, or in utero DES exposure justifies the exploration of a screening policy for EP among these women. If a risk factor reduces fertility chances, the OR detected when using pregnant controls is higher than the OR calculated using nonpregnant controls.

The accuracy of hysterosalpingography in the diagnosis of tubal pathology: a meta-analysis

OBJECTIVE To assess the value of hysterosalpingography (HSG) in diagnosing tubal patency and peritubal adhesions using laparoscopy with chromopertubation as the gold standard. DESIGN Meta-analysis of 20 studies comparing HSG and laparoscopy for tubal patency and peritubal adhesions. PATIENTS Four thousand one hundred seventy-nine patients with infertility in 20 studies. INTERVENTION Hysterosalpingography and diagnostic laparoscopy as part of infertility workup. MAIN OUTCOME MEASURE Tubal patency and peritubal adhesions. RESULTS For tubal patency the reported sensitivity and specificity differed between studies. In a subset of studies that evaluated HSG and laparoscopy independently, a point estimate of 0.65 for sensitivity and 0.83 for specificity was calculated. For peritubal adhesions a summary receiver operating characteristic curve could be estimated. CONCLUSIONS Although HSG is of limited use for detecting tubal patency because of its low sensitivity, its high specificity makes it a useful test for ruling in tubal obstruction. For the evaluation of peritubal adhesions HSG is not reliable.

The performance of CA-125 measurement in the detection of endometriosis: a meta-analysis

OBJECTIVE To assess the diagnostic performance of serum CA-125 measurement in the detection of endometriosis. DESIGN Meta-analysis. SETTING AND PATIENT(S) Twenty-three studies comparing serum CA-125 levels and laparoscopically confirmed endometriosis. INTERVENTION(S) Serum CA-125 measurement and laparoscopy. MAIN OUTCOME MEASURE(S) Sensitivity and specificity of serum CA-125 measurement in the diagnosis of endometriosis with laparoscopy as the reference standard. RESULT(S) The estimated summary receiver operating characteristic curves showed that the performance of serum CA-125 measurement in the diagnosis of endometriosis grade I/IV is limited, whereas its performance in the diagnosis of endometriosis grade III/IV is better. CONCLUSION(S) Despite its limited diagnostic performance, we believe that the routine use of serum CA-125 measurement in patients with infertility might be justified. In contrast to laparoscopy, serum CA-125 measurement is an inexpensive test that is not a burden for the patient. It could identify a subgroup of patients who are more likely to benefit from early laparoscopy. Studies reporting on the mutual dependence between serum CA-125 measurement and data from the history and physical examination are needed.

Effect of clomifene citrate plus metformin and clomifene citrate plus placebo on induction of ovulation in women with newly diagnosed polycystic ovary syndrome: randomised double blind clinical trial

Abstract Objective To compare the effectiveness of clomifene citrate plus metformin and clomifene citrate plus placebo in women with newly diagnosed polycystic ovary syndrome. Design Randomised clinical trial. Setting Multicentre trial in 20 Dutch hospitals. Participants 228 women with polycystic ovary syndrome. Interventions Clomifene citrate plus metformin or clomifene citrate plus placebo. Main outcome measure The primary outcome measure was ovulation. Secondary outcome measures were ongoing pregnancy, spontaneous abortion, and clomifene resistance. Results 111 women were allocated to clomifene citrate plus metformin (metformin group) and 114 women were allocated to clomifene citrate plus placebo (placebo group). The ovulation rate in the metformin group was 64% compared with 72% in the placebo group, a non-significant difference (risk difference − 8%, 95% confidence interval − 20% to 4%). There were no significant differences in either rate of ongoing pregnancy (40% v 46%; − 6%, − 20% to 7%) or rate of spontaneous abortion (12% v 11%; 1%, − 7% to 10%). A significantly larger proportion of women in the metformin group discontinued treatment because of side effects (16% v 5%; 11%, 5% to 16%). Conclusion Metformin is not an effective addition to clomifene citrate as the primary method of inducing ovulation in women with polycystic ovary syndrome. Trial registration Current Controlled Trials ISRCTN55906981 [controlled-trials.com][controlled-trials.com].

Propagation of human spermatogonial stem cells in vitro.

CONTEXT Young boys treated with high-dose chemotherapy are often confronted with infertility once they reach adulthood. Cryopreserving testicular tissue before chemotherapy and autotransplantation of spermatogonial stem cells at a later stage could theoretically allow for restoration of fertility. OBJECTIVE To establish in vitro propagation of human spermatogonial stem cells from small testicular biopsies to obtain an adequate number of cells for successful transplantation. DESIGN, SETTING, AND PARTICIPANTS Study performed from April 2007 to July 2009 using testis material donated by 6 adult men who underwent orchidectomy as part of prostate cancer treatment. Testicular cells were isolated and cultured in supplemented StemPro medium; germline stem cell clusters that arose were subcultured on human placental laminin-coated dishes in the same medium. Presence of spermatogonia was determined by reverse transcriptase polymerase chain reaction and immunofluorescence for spermatogonial markers. To test for the presence of functional spermatogonial stem cells in culture, xenotransplantation to testes of immunodeficient mice was performed, and migrated human spermatogonial stem cells after transplantation were detected by COT-1 fluorescence in situ hybridization. The number of colonized spermatogonial stem cells transplanted at early and later points during culture were counted to determine propagation. MAIN OUTCOME MEASURES Propagation of spermatogonial stem cells over time. RESULTS Testicular cells could be cultured and propagated up to 15 weeks. Germline stem cell clusters arose in the testicular cell cultures from all 6 men and could be subcultured and propagated up to 28 weeks. Expression of spermatogonial markers on both the RNA and protein level was maintained throughout the entire culture period. In 4 of 6 men, xenotransplantation to mice demonstrated the presence of functional spermatogonial stem cells, even after prolonged in vitro culture. Spermatogonial stem cell numbers increased 53-fold within 19 days in the testicular cell culture and increased 18,450-fold within 64 days in the germline stem cell subculture. CONCLUSION Long-term culture and propagation of human spermatogonial stem cells in vitro is achievable.

High mutation rates have driven extensive structural polymorphism among human Y chromosomes

Although much structural polymorphism in the human genome has been catalogued, the kinetics of underlying change remain largely unexplored. Because human Y chromosomes are clonally inherited, it has been possible to capture their detailed relationships in a robust, worldwide genealogical tree. Examination of structural variation across this tree opens avenues for investigating rates of underlying mutations. We selected one Y chromosome from each of 47 branches of this tree and searched for large-scale variation. Four chromosomal regions showed extensive variation resulting from numerous large-scale mutations. Within the tree encompassed by the studied chromosomes, the distal-Yq heterochromatin changed length ≥12 times, the TSPY gene array changed length ≥23 times, the 3.6-Mb IR3/IR3 region changed orientation ≥12 times and the AZFc region was rearranged ≥20 times. After determining the total time spanned by all branches of this tree (∼1.3 million years or 52,000 generations), we converted these mutation counts to lower bounds on rates: ≥2.3 × 10−4, ≥4.4 × 10−4, ≥2.3 × 10−4 and ≥3.8 × 10−4 large-scale mutations per father-to-son Y transmission, respectively. Thus, high mutation rates have driven extensive structural polymorphism among human Y chromosomes. At the same time, we found limited variation in the copy number of Y-linked genes, which raises the possibility of selective constraints.

Using an electrocautery strategy or recombinant follicle stimulating hormone to induce ovulation in polycystic ovary syndrome: randomised controlled trial

Abstract Objective To compare the effectiveness of an electrocautery strategy with ovulation induction using recombinant follicle stimulating hormone in patients with polycystic ovary syndrome. Design Randomised controlled trial. Setting Secondary and tertiary hospitals in the Netherlands. Participants 168 patients with clomiphene citrate resistant polycystic ovary syndrome: 83 were allocated electrocautery and 85 were allocated recombinant follicle stimulating hormone. Intervention Laparoscopic electrocautery of the ovaries followed by clomiphene citrate and recombinant follicle stimulating hormone if anovulation persisted, or induction of ovulation with recombinant follicle stimulating hormone. Main outcome measure Ongoing pregnancy within 12 months. Results. The cumulative rate of ongoing pregnancy after recombinant follicle stimulating hormone was 67%. With only electrocautery it was 34%, which increased to 49% after clomiphene citrate was given. Subsequent recombinant follicle stimulating hormone increased the rate to 67% at 12 months (rate ratio 1.01, 95% confidence interval 0.81 to 1.24). No complications occurred from electrocautery with or without clomiphene citrate. Patients allocated to electrocautery had a significantly lower risk of multiple pregnancy (0.11, 0.01 to 0.86). Conclusion The ongoing pregnancy rate from ovulation induction with laparoscopic electrocautery followed by clomiphene citrate and recombinant follicle stimulating hormone if anovulation persisted, or recombinant follicle stimulating hormone, seems equivalent to ovulation induction with recombinant follicle stimulating hormone, but the former procedure carries a lower risk of multiple pregnancy.

The accuracy of serum chlamydial antibodies in the diagnosis of tubal pathology: a meta-analysis

OBJECTIVE To assess the discriminative capacity of Chlamydia antibody titers in the diagnosis of tubed pathology in subfertile patients. DESIGN Meta-analysis of studies comparing Chlamydia antibody titers and laparoscopy for tubal patency and peritubal adhesions. PATIENTS A total of 2,729 patients with subfertility in 23 studies. INTERVENTION(S) Chlamydia antibody titer and laparoscopy as part of subfertility work-up. MAIN OUTCOME MEASURE Sensitivity and specificity of Chlamydia antibody titers in the diagnosis of tubal pathology using laparoscopy with chromopertubation as the reference standard. RESULT(S) The discriminative capacity of Chlamydia antibody titers depended on the type of assay that was used. Summary receiver operating characteristic (ROC) curves of studies using ELISA or (micro)immunofluorescence revealed a better discrimination than the summary ROC-curve of studies using immunoperoxidase assay. CONCLUSION(S) The discriminative capacity of Chlamydia antibody titers by means of ELISA, microimmunofluorescence, or immunofluorescence in the diagnosis of any tubal pathology is comparable to that of hysterosalpingography (HSG) in the diagnosis of tubal occlusion. Chlamydia antibody testing involves little burden but provides no details on the anatomy of uterus and tubes. Whether or not Chlamydia antibody testing can replace HSG depends on the perspective taken in the diagnostic work-up of subfertility.