STUDY QUESTION

What is the intracellular concentration of cryoprotectant (ICCP) in mouse zygotes during vitrification (VIT) and slow-freezing (SLF) cryopreservation procedures?

SUMMARY ANSWER

Contrary to common beliefs, it was observed that the ICCP in vitrified zygotes is lower than after SLF, although the solutions used in VIT contain higher concentrations of cryoprotectants (CPs).

WHAT IS KNOWN ALREADY

To reduce the likelihood of intracellular ice crystal formation, which has detrimental effects on cell organelles and membranes, VIT was introduced as an alternative to SLF to cryopreserve embryos and gametes. Combined with high cooling and warming rates, the use of high concentrations of CPs favours an intracellular environment that supports and maintains the transition from a liquid to a solid glass-like state devoid of crystals. Although the up-to-date publications are reassuring in terms of obstetric and perinatal outcomes after VIT, a fear about exposing gametes and embryos to high amounts of CPs that exceed 3–4-fold those found in SLF was central to a debate initiated by advocates of SLF procedures.

STUDY DESIGN, SIZE, DURATION

Two experimental set-ups were applied. The objective of a first study was to determine the ICCP at the end of the exposure steps to the CP solutions with our VIT protocol (n = 31). The goal of the second investigation was to compare the ICCP between VIT (n = 30) and SLF (n = 30). All experiments were performed in triplicates using mouse zygotes. The study took place at the GIGA-Research Institute of the University of Liège.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Cell volume is modified by changes in extracellular osmolarity. Hence, we estimated the final ICCP after the incubation steps in the VIT solutions by exposing the cells to sucrose (SUC) solutions with defined molarities. The ICCP was calculated from the SUC concentration that produced no change in cell volume, i.e. when intra- and extracellular osmolarities were equivalent. Cell volume was monitored by microscopic cinematography. ICCP was compared between SLF and VIT based on the principle that a high ICCP lowers the probability of (re)crystallization during warming but increases the probability of over-swelling of the cell due to fast inflow of water. The survival rates of mouse zygotes after SLF or VIT were compared using either (i) various warming rates or (ii) various concentrations of SUC in the warming dilution medium.

MAIN RESULTS AND THE ROLE OF CHANCE

The ICCP in mouse zygotes during the VIT procedure prior to plunging them in liquid nitrogen was ~2.14 M, i.e. one-third of the concentration in the VIT solution. After SLF, the warming rate did not affect the zygote survival rate. In contrast, only 3/30 vitrified zygotes survived when warmed slowly but as many as 30/30 zygotes survived when warming was fast (>20 000°C/min). Vitrified zygotes showed significantly higher survival rates than slow-frozen zygotes when they were placed directly in the culture medium or in solutions containing low concentrations of SUC (P < 0.01). These two experiments demonstrate a lower ICCP after VIT than after SLF.

LIMITATIONS, REASONS FOR CAUTION

The results should not be directly extrapolated to other stages of development or to other species due to possible differences in membrane permeability to water and CPs.

WIDER IMPLICATIONS OF THE FINDINGS

The low ICCP we observed after VIT removes the concern about high ICCP after VIT, at least in murine zygotes and helps to explain the observed efficiency and lack of toxicity of VIT.

STUDY FUNDING / COMPETING INTEREST(S)

The study was funded by the FNRS (National Funds for Scientific Research). The authors declare that they have no competing interests.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/8/2101?rss=1

Recommendation and review posted by G. Smith

STUDY QUESTION

Should oocytes showing the presence of smooth endoplasmic reticulum aggregates (SER) be considered for embryo transfer?

SUMMARY ANSWER

The present study shows that embryos derived from metaphase II oocyte with visible SER (SER+MII) have the capacity to develop normally and may lead to newborns with no major malformations.

WHAT IS KNOWN ALREADY

It has been reported that the presence of SER in the cytoplasm of oocytes has a negative impact on embryo development, and is associated with a decreased clinical outcome and an increased risk of congenital anomalies. Therefore, it has been recommended that embryos derived from SER-positive oocytes should not be transferred.

STUDY DESIGN, SIZE, DURATION

Consecutive ICSI cycles with at least one SER+MII oocyte were retrospectively analyzed regarding embryological and pregnancy outcome and compared with ICSI cycles showing only oocytes without SER (SER–MII).

PARTICIPANTS/MATERIALS, SETTING, METHODS

In total, 394 SER-positive (SER+) cycles and 6845 SER-negative (SER–) cycles were analyzed. The Student's t-test, one-way analysis of variance test and ² test were used for statistical analysis. P value of <0.05 was considered statistically significant.

MAIN RESULTS AND THE ROLE OF CHANCE

Comparable fertilization rates were observed in SER+ (76.2%) and SER– (73.5%) cycles. In case of blastocyst culture, the cycle efficiency was lower in SER+ than in SER– cycles (mean 42.2 versus 62.8%, P < 0.001). The pregnancy and clinical pregnancy (CP) rates per embryo transfer (ET) were comparable for SER+ and SER– cycles (37.6 versus 37.8% and 33.0 versus 32.4%, respectively).

In the SER+ cycles, the fertilization rates of SER+MII and SER–MII (72.9 versus 77.0%), as well as the capacity to develop into good-quality embryos on Days 3 (62.3 versus 63.7%) and 5 (45.4 versus 47.4%), were similar. In the 364 SER+ cycles, the ETs were subdivided in: ET with only SER+MII (n = 31; 8.5%), ET with only SER–MII (n = 235; 64.5%) and ET with mixed SER+ and SER–MII (n = 98; 26.9%). The pregnancy (25.8, 37.4 and 41.8%, respectively) and CP rates (22.6, 32.4 and 37.9%, respectively) were not different between the three subgroups. Among the cycles with known outcome, there was no difference in the rate of major malformations between SER+ cycles (5.3%) and SER– cycles (2.1%). Moreover, no major malformations were reported from the live borns definitely originating from SER+MII embryos. In addition, three newborns, from single ET with frozen–thawed embryos originating from SER+MII oocytes, were delivered and presented no major malformation.

LIMITATIONS, REASONS FOR CAUTION

Taking into account the previous publications and our neonatal data, a follow-up of the children born after ET with embryos originating from SER+ cycles is encouraged.

WIDER IMPLICATION OF THE FINDINGS

More studies should be performed to investigate the origin and effect of SER aggregates on the molecular status of oocytes and embryos.

STUDY FUNDING/COMPETING INTEREST(S)

No external funding was either sought or obtained for this study and there are no potential competing interests.

TRIAL REGISTRATION NUMBER

Not applicable.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/8/2111?rss=1

Recommendation and review posted by G. Smith

STUDY QUESTION

How effective is the vaginal administration of misoprostol in dilating the cervix prior to inserting an intrauterine device (IUD) in nulligravidas?

SUMMARY ANSWER

The use of misoprostol at a dose of 400 µg administered vaginally 4 h prior to IUD insertion increased the ease of insertion and reduced the incidence of pain during the procedure, although the frequency of cramps increased following misoprostol use.

WHAT IS KNOWN AND WHAT THIS PAPER ADDS

Misoprostol has been widely used in Obstetrics and Gynecology; however, its usefulness and efficacy in facilitating IUD insertion in nulligravidas have yet to be established. The present study shows that the benefits of misoprostol use prior to IUD insertion include facilitating insertion and reducing pain during the procedure; therefore, weighing up the benefits encountered against the only negative side effect (cramps prior to insertion), these results suggest that misoprostol use should become standard practice to facilitate IUD insertion in nulligravidas.

STUDY DESIGN, SIZE DURATION

A randomized, double-blind clinical trial was conducted.

PARTICIPANTS/MATERIALS, SETTING METHODS

Nulligravid women of reproductive age were submitted to IUD insertion between July 2009 and November 2011 at the Instituto de Medicina Integral Prof. Fernando Figueira in Recife, Pernambuco, Brazil. A total of 179 women were randomly allocated to two groups: 86 to receive 400 µg of misoprostol vaginally 4 h prior to IUD insertion and 93 to receive placebo. Risk ratios (RRs) were calculated as measures of relative risk, together with their 95% confidence intervals (95% CI). The number needed to treat (NNT) and the number needed to harm (NNH) were also calculated.

MAIN RESULTS AND THE ROLE OF CHANCE

Significant differences were found between the groups for all the immediate end points studied, with less difficulty in inserting the IUD [RR = 0.49 (23/86 versus 51/93); 95% CI: 0.33–0.72; P = 0.00005], a lower risk of dilatation <4 mm [RR = 0.48 (24/86 versus 54/93); 95% CI: 0.33–0.70; P = 0.0001], a reduction in moderate-to-severe pain at IUD insertion [RR = 0.56 (32/86 versus 62/93]; 95% CI: 0.41–0.76; P = 0.00008), as well as a lesser likelihood of experiencing a disagreeable or very disagreeable sensation [RR = 0.49(29/86 versus 64/93); 95% CI: 0.35–0.68; P = 0.000004] in the group that was given misoprostol compared with the group that received placebo. There was no significant difference between the groups in relation to complications during IUD insertion. There were no cases of uterine perforation in either group. The frequency of cramps was 40% higher in the misoprostol group.

LIMITATIONS, REASONS FOR CAUTION

The present study showed a positive balance between the benefits and risks of the use of misoprostol; however, it is not feasible to conclude that its use is imperative prior to IUD insertion in nulligravidas and IUD insertion should not be canceled when the medication is unavailable.

WINDER IMPLICATIONS OF THE FINDINGS

In view of its effect in promoting cervical dilatation, misoprostol may be used prior to IUD insertion both in nulligravidas and in any women with cervical stenosis irrespective of parity.

STUDY FUNDING

This study was funded by the Instituto de Medicina Integral Prof Fernando Figueira.

COMPETING INTERESTS

None.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/8/2118?rss=1

Recommendation and review posted by G. Smith

STUDY QUESTION

Are interleukin-33 (IL-33) serum levels higher in women with uterine leiomyoma compared with controls without leiomyoma?

SUMMARY ANSWER

Serum IL-33 is elevated in women with uterine leiomyoma and correlated with features of uterine leiomyoma tumour burden, namely fibroid number, size and weight.

WHAT IS KNOWN ALREADY

Uterine leiomyomas are the most common benign tumours in premenopausal women associated with major tissue fibrosis. IL-33 is a cytokine involved in fibrotic disorders. The potential role of IL-33 in leiomyoma has not been reported before.

STUDY DESIGN, SIZE, DURATION

This is a prospective laboratory study conducted in a tertiary-care university hospital between January 2005 and December 2010. We investigated non-pregnant, 42-year-old patients (n = 151) during surgery for a benign gynaecological condition.

PARTICIPANTS/MATERIALS, SETTING, METHODS

After complete surgical exploration of the abdominopelvic cavity, 59 women with histologically proved uterine leiomyoma and 92 leiomyoma-free control women were enrolled. Women with endometriosis or past history of ovarian malignancy and borderline tumours were not included. The control group included women with benign ovarian cysts, paratubal cysts or tubal defects without any evidence of uterine leiomyoma. For each patient, a structured questionnaire was completed during a face-to-face interview conducted by the surgeon during the month preceding surgery. Serum samples were obtained in the month preceding the surgical procedures according to the menstrual phase or hormonal therapy. IL-33 was measured in sera by enzyme-linked immunosorbent assay, and correlation of IL-33 concentration with the extent and severity of the disease was investigated.

MAIN RESULTS AND THE ROLE OF CHANCE

IL-33 was detected in 32 (54.2%) women with leiomyoma and 18 (19.6%) controls (P < 0.001). Serum IL-33 was higher in women with leiomyoma (median, 140.1 pg/ml; range, 7.5–2247.7) than in controls (median, 27.8 pg/ml; range, 7.5–71.6; P = 0.002). We found positive correlations between serum IL-33 concentration and leiomyoma features, such as fibroid weight (r = 0.630; P = 0.001) and size (r = 0.511; P = 0.018) and the number of fibroids (r = 0.503; P = 0.003).

LIMITATIONS, REASONS FOR CAUTION

There was a possible selection bias due to inclusion of only surgical patients. Therefore our control group consisted of women who underwent surgery for benign gynaecological conditions. This may lead to biases stemming from the fact that certain of these conditions, such as tubal infertility or ovarian cysts, might be associated with altered serum IL-33 levels.

WIDER IMPLICATIONS OF THE FINDINGS

We demonstrate for the first time that elevated serum IL-33 levels are associated with the existence of uterine leiomyoma. However, even if an association does not constitute proof of cause and effect, investigating the mechanisms that underlie fibrogenesis associated with leiomyomas is a step towards understanding this enigmatic disease. This study opens the doors to future, more mechanistics studies to establish the exact role of IL-33 in uterine leiomyomas pathogenesis.

STUDY FUNDING/COMPETING INTEREST(S)

No funding, no conflict of interest.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/8/2126?rss=1

Recommendation and review posted by G. Smith

STUDY QUESTION

Does fallopian tube sperm perfusion (FSP) result in better pregnancy and live birth rates than standard intrauterine insemination (SIUI) for couples with non-tubal infertility with or without gonadotrophin or clomiphene stimulation?

SUMMARY ANSWER

There was no evidence of an improvement in live birth rates with FSP compared with SIUI.

WHAT IS KNOWN ALREADY

Previous randomized controlled trials have suggested improved live birth rates with FSP but these trials were small. A systematic review published in 2004 suggested heterogeneity in results.

STUDY DESIGN, SIZE, AND DURATION

This pragmatic, multicentre, randomized controlled trial compared SIUI and FSP in 417 women with non-tubal infertility.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The patients were treated at fertility clinics in New Zealand, Australia and the United Arab Emirates.

MAIN RESULTS AND THE ROLE OF CHANCE

Four hundred and seventeen women were randomized to SIUI (n = 210) or FSP (n = 207). Data were available for analysis from 198 women in the SIUI group and 198 women in the FSP group. There were 19 women with incomplete data because of cycle cancellation or withdrawals and 2 women who conceived prior to commencing treatment. There were no significant differences in live birth rates between the two groups with 27 (12.9%) in the SIUI group and 21 in the FSP group (10.1%) [Odds Ratio (OR) 1.31 (0.71, 2.39), P = 0.48]. Two ectopic pregnancies were reported in the SIUI group and one was reported in the FSP group.

LIMITATIONS, REASONS FOR CAUTION

Different ovulation protocols were used in the different clinics. Approximately 10% of the cycles involved donor sperm and ~5% of the cycles did not complete the assigned intervention.

WIDER IMPLICATIONS OF THE FINDINGS

There was no evidence of an improvement in live birth rates with FSP compared with SIUI.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded in part by the A+ trust of the Auckland District Health Board. No commercial funding was received.

TRIAL REGISTRATION NUMBER

ANZCTR Number ACTRN12612001303831.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/8/2134?rss=1

Recommendation and review posted by G. Smith

STUDY QUESTION

Do the presence of endometriomas and their laparoscopic excision lead to a decrease in ovarian reserve as assessed by serum anti-Müllerian hormone (AMH) levels?

SUMMARY ANSWER

Both the presence and excision of endometriomas cause a significant decrease in serum AMH levels, which is sustained 6 months after surgery.

WHAT IS KNOWN ALREADY

No previous comparison of serum AMH levels between women with and without endometrioma has been reported. However, studies have suggested a decline in serum AMH levels 1–3 months after endometrioma excision but long-term data are needed.

STUDY DESIGN, SIZE, DURATION

A prospective cohort study including 30 women with endometrioma >2 cm were age matched with 30 healthy women without ovarian cysts.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Women with endometrioma underwent laparoscopic excision with the stripping technique. Serum AMH level and antral follicle count (AFC) were determined preoperatively, 1 and 6 months after surgery. Correlation analyses were undertaken in order to identify determinants of surgery-related change in ovarian reserve.

MAIN RESULTS AND THE ROLE OF CHANCE

Compared with controls at baseline, women with endometrioma had lower AMH levels (4.2 ± 2.3 versus 2.8 ± 2.2 ng/ml, respectively, P = 0.02) and AFC (14.7 ± 4.1 versus 9.7 ± 4.8, respectively, P < 0.01). Serum AMH levels were further decreased 6 months after surgery (2.8 ± 2.2 versus 1.8 ± 1.3 ng/ml, P = 0.02), while AFC remained unchanged (9.7 ± 4.8 versus 10.4 ± 4.2, P = 0.63). The rate of decline in AMH was not correlated with age, laterality of endometrioma, cyst diameter or the number of primordial follicles on the surgical specimens. The preoperative serum AMH level was positively correlated with the rate of decline in serum AMH after surgery (r = 0.47, P = 0.02).

LIMITATIONS, REASONS FOR CAUTION

The absence of a non-treated group of women with endometriomas as a further control prevents comment on the presence of a progressive decline in ovarian reserve related to endometrioma per se. The sample size may be too small for detection of factors correlated with the extent of ovarian damage.

WIDER IMPLICATIONS OF THE FINDINGS

While the findings are mostly in agreement with previous studies, the present study is the first to show that the presence of endometrioma per se is associated with a decrease in ovarian reserve. The extent of surgery-related decline in ovarian reserve is not predictable using preoperative or perioperative factors. It may be prudent to measure AMH levels preoperatively and delay/avoid surgical excision as far as is possible if subsequent fertility is a concern. Additional studies are required to further investigate whether the endometrioma-related decline in ovarian reserve per se is progressive in nature and whether it exceeds the surgery-related decline.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by the Research Fund of the Uludag University School of Medicine. The authors have no conflict of interest associated with this study.

Source:
http://humrep.oxfordjournals.org/cgi/content/short/28/8/2140?rss=1

Recommendation and review posted by G. Smith