Angiogenic factors and the lectin pathway of complement in women with secondary recurrent pregnancy loss.

The poor remodeling of placental spiral arteries seen in preeclampsia is also discussed to contribute to recurrent pregnancy loss (RPL) preceded by abnormal angiogenesis and excessive complement activation. Low levels of Mannose-binding-lectin (MBL), a pattern recognition molecule (PRM) of the lectin pathway, have been found in women with RPL. We propose that pregnancy loss is connected to defective angiogenesis with reperfusion damage in the placenta and decreased levels of PRM in the lectin pathway in women with RPL. In this cohort study, we investigate the angiogenic factors and the lectin complement pathway in early pregnancy and their time-dependent relationship with pregnancy outcomes in 76 women with secondary RPL (sRPL) who have at least four prior pregnancy losses and a live birth. We evaluated levels of Angiopoietin-1 (Ang-1), Angiopoietin-2 (Ang-2), Vascular Endothelial Growth Factor (VEGF), soluble fms-like tyrosine kinase-1 (sFlt-1), and the PRMs, MBL, ficolin-1, -2, -3 and an additional soluble PRM, Pentraxin-3, during the 5th, 6th, and 7th gestational weeks. Our results showed that, compared to live births, pregnancies that ended in loss were associated with elevated VEGF levels and decreased levels of the Ang-2/Ang-1 ratio. Also, increasing levels of ficolin-2 were significantly associated with pregnancy loss, with MBL showing no association. Our research suggests that women with sRPL may have inadequate placentation with impaired angiogenesis in pregnancies ending in a loss.

Maternal carriage of H-Y restricting HLA class II alleles is a negative prognostic factor for women with recurrent pregnancy loss after birth of a boy.

Immune system aberrations are suggested to be an important factor in the pathophysiology of unexplained secondary recurrent pregnancy loss (sRPL). The objective was to investigate if the sex ratio of the firstborn child in sRPL patients differs from the background population and whether the sex of the firstborn child has a negative impact on the pregnancy prognosis alone and/or in combination with carriage of male-specific minor histocompatibility (H-Y) restricting HLA class II alleles. From January 2016 to October 2022, 582 patients with unexplained RPL were admitted to the RPL Center of Western Denmark and continuously followed-up. HLA-DRB1 and -DQB1 typing was performed as part of the routine diagnostic work-up. In sRPL patients, a history of a firstborn boy was significantly more frequent than in the Danish background population and was associated with significantly lower odds of a successful reproductive outcome in the first pregnancy after admission compared to a firstborn girl (OR=0.41, 95% CI: 0.20-0.83, p = 0.014). The odds of a successful reproductive outcome were enhanced in patients carrying ≥ 1 H-Y-restricting HLA class II alleles with a first-born girl compared to a firstborn boy (OR=3.33, 95% CI: 1.40-7.88, p = 0.005), while no difference in successful reproductive outcome was seen in sRPL patients not carrying these alleles (OR=1.20, 95% CI: 0.33-4.43, p = 0.781). The sex ratio of children born after RPL was similar to the Danish background population. These findings confirm previous findings and suggests that a harmful immune response triggered by H-Y-antigen exposure during a previous pregnancy in preconditioned women may cause sRPL.

Plasma level of mannose-binding lectin is associated with the risk of recurrent pregnancy loss but not pregnancy outcome after the diagnosis.

STUDY QUESTION: Are low or high plasma mannose-binding lectin (p-MBL) levels associated with recurrent pregnancy loss (RPL) and the reproductive and perinatal outcomes before and after RPL? SUMMARY ANSWER: The prevalence of low p-MBL levels was significantly higher in RPL patients, while high levels were significantly less prevalent. No association was found between p-MBL level and reproductive and perinatal outcomes before and after RPL. WHAT IS KNOWN ALREADY: Mannose-binding lectin (MBL) is an important component in the innate immune system. Low p-MBL levels have been associated with RPL, while the correlation with high levels has been poorly studied. Adverse perinatal outcomes are generally more frequent among RPL patients, but reports concerning the association between maternal p-MBL levels and perinatal outcomes, including birth weight (BW) and gestational age (GA), are conflicting. STUDY DESIGN SIZE DURATION: This study was a combined cross-sectional and cohort study of 267 RPL patients admitted to the RPL Center of Western Denmark between January 2016 and March 2020. RPL patients were followed until birth of a liveborn child or until end of follow-up, March 2021. A sample of 185 healthy female blood donors of reproductive age was used as a MBL reference group. PARTICIPANTS/MATERIALS SETTING METHODS: All RPL patients had ≥3 consecutive pregnancy losses, a regular menstrual cycle and no known significant chromosomal or uterine malformations. At the first consultation, routine blood samples including p-MBL measurement and detailed obstetrical and perinatal information were collected. p-MBL levels in RPL patients were compared to the MBL reference group. A logistic regression analysis adjusted for relevant confounders assessed the association between low p-MBL levels and an unsuccessful reproductive outcome in RPL patients in first pregnancy after admission. Perinatal outcomes before and after RPL were compared between RPL subgroups according to low (≤500 µg/l), intermediate (501-3000 µg/l) and high (>3000 µg/l) p-MBL levels. MAIN RESULTS AND THE ROLE OF CHANCE: Significantly more RPL patients had low p-MBL levels (prevalence proportion ratio (PPR): 1.79, 95% CI: 1.34-2.38) and fewer had high p-MBL levels (PPR: 0.56, 95% CI: 0.40-0.79) compared to the reference group, while the prevalence of intermediate p-MBL level was not different between the groups (PPR: 0.86, 95% CI: 0.69-1.08). In the prospective study, low p-MBL level was not a significant risk factor for a pregnancy loss in the first pregnancy after admission after adjustment for age, BMI and smoking. Neither before nor after the RPL diagnosis were maternal p-MBL levels significantly associated with BW or GA. LIMITATIONS REASONS FOR CAUTION: Only 161 (60.3%) patients had given birth after RPL during the follow-up period, which limited the possibility to detect clear associations between p-MBL levels and perinatal outcomes after RPL. WIDER IMPLICATIONS OF THE FINDINGS: In agreement with several previous studies, low p-MBL levels are strongly associated with RPL, while this study for the first time documents that high levels may play a protective role, which suggests a causal relationship. We suggest that larger prospective studies evaluate the association between p-MBL levels and RPL prognosis. STUDY FUNDING/COMPETING INTERESTS: No external funding was received. We acknowledge the Department of Obstetrics and Gynaecology at Aalborg University Hospital for financial support. U.S.K. has reported personal fees from Merck, consulting fees from IBSA Nordic, and a grant from Gedeon Richter, Merck and IBSA Nordic outside of the submitted work. TRIAL REGISTRATION NUMBER: ID from clinicaltrials.gov is NCT04017754.

Seminal plasma metabolomics profiles following long (4-7 days) and short (2 h) sexual abstinence periods.

OBJECTIVE: Metabolomic profiling of seminal plasma has been suggested as a possible approach for a fast and non-invasive male infertility evaluation diagnosis. However, metabolomics profiles in normozoospermic men have not been thoroughly investigated, and the influence of ejaculation-abstinence has not been described. To provide interim reference values and find associations between the metabolomics profiles of human seminal plasma and length of ejaculation-abstinence period in normozoospermic men. STUDY DESIGN: Semen samples collected after long (4-7 days) and short abstinence (2 h) from 31 normozoospermic males were assessed for routine quality parameters before the seminal plasma was separated by centrifugation. Metabolomics profiles of the seminal plasma were then determined using untargeted Nuclear Magnetic Resonance Spectroscopy. RESULTS: In total, 30 metabolites were identified. Pyruvate showed a higher concentration, while fructose, acetate, choline, methanol, N-acetylglucosamine, O-acetylcarnitine, uridine, and sn-glycero-3-phosphocoline showed lower concentrations in samples collected after short abstinence (vs. long). All metabolites showed lower absolute amounts (volume × concentration) following shorter abstinence. However, the lower sperm concentration in samples collected after short abstinence resulted in higher absolute amounts of pyruvate and taurine per spermatozoa: pyruvate 1.92 (1.12-3.87) vs. 1.29 (0.83-2.62) (P < 0.001) and taurine 0.58 (0.36-0.92) vs. 0.43 (0.28-0.95) (P < 0.05) ng/106 spermatozoa. Simultaneously, there was a higher percentage of progressively motile spermatozoa in samples collected after the short abstinence. CONCLUSION: The generally lower concentrations of seminal metabolites after short abstinence periods may be related to the shorter time available for secretion and collection of these metabolites by the accessory glands and the epididymides. The concomitant lower number of spermatozoa in the second ejaculate resulted in increased absolute amounts of pyruvate and taurine per spermatozoa, accompanied by increased spermatozoa motility in these samples. The simultaneous increase in percentages of motile spermatozoa and absolute amounts of pyruvate and taurine per spermatozoa after shorter abstinence might indicate that these two metabolites play a more critical role in sperm motility, which should be further investigated in future studies.

HLA-DRB1 polymorphism in recurrent pregnancy loss: New evidence for an association to HLA-DRB1*07.

Many cases of recurrent pregnancy loss (RPL) defined as ≥3 consecutive pregnancy losses are suggested to be caused by an aberrant maternal immune response against the fetus or trophoblast. Human leukocyte antigen (HLA)-DRB1 and -DQB1 polymorphisms are associated with most autoimmune disorders and studies of HLA-DBB1 polymorphism in RPL patients are thus relevant. In previous studies, the HLA-DRB1*03 allele was found with increased prevalence in RPL patients. We wanted to clarify whether HLA-DRB1 alleles indeed were associated with RPL among women of Caucasian descent. A total of 1078 women with unexplained RPL and 2066 bone marrow donors were HLA-DRB1-typed and subsets were also HLA-DQB1 typed. All patients were initially HLA-DRB1-typed by DNA-based low-resolution techniques and subsets of patients and all controls were typed by high-resolution techniques. Among patients, the HLA-DRB1*07 allele frequency was significantly increased compared with controls; OR 1.29 (95 % CI 1.09-1.52), p < 0.0025; after correction for multiple comparisons pc = 0.031. The HLA-DRB1*07/*07 genotype was highly increased in patients with RPL compared with controls: OR 2.27 (1.31-3.93), p = 0.0027. The frequency of the HLA-DRB1*07 phenotype in RPL patients had increased significantly (p = 0.002) in three studies from our group published 1994-2021. The allele frequency of HLA-DRB1*03 was not increased in RPL patients compared with controls; OR 0.96 (0.83-1.12). In conclusion, the previous association between HLA-DRB1*03 and RPL could not be confirmed in our study whereas an association to HLA-DRB1*07 was detected for the first time. Since the latter association is a new finding, it should be confirmed in future studies.

Chance of live birth in the first pregnancy after referral among patients with recurrent pregnancy loss is not influenced by their relatives' reproductive history.

Purpose: Recurrent pregnancy loss (RPL) is defined as three or more consecutive pregnancy losses and affects 1-3% of couples trying to conceive. Pregnancy loss is more common among RPL patients' siblings than in the general population. Our objective was to investigate whether first-degree relatives with pregnancy losses influenced the chance of live birth in the first pregnancy after referral among women with RPL.Materials and methods: This is a cohort study of 2138 women with RPL seen at the Danish RPL Unit at Copenhagen University Hospital, Rigshospitalet between January 1st 2000 and December 31st 2017 with follow-up until December 2018. Pregnancies among first-degree relatives were reported by patients at their first consultation. Chance of live birth after referral was compared by logistic regression analysis.Results: Overall, 76% of the referred women achieved a pregnancy after referral and of these, 58% delivered a live born child. Women whose mother had experienced pregnancy loss were referred at a younger age than women with no pregnancy losses among first-degree relatives (mean age 33.6 (SD 4.6) versus 34.3 (SD 4.5), p = 0.002). Pregnancy losses among first-degree relatives did not influence chance of live birth.Conclusions: Our results indicate that pregnancy losses among first-degree family members is not an important risk factor for outcome of the first pregnancy after referral among women with RPL.

Pregnancy outcomes after recurrent pregnancy loss: a longitudinal cohort study on stress and depression.

RESEARCH QUESTION: Are self-reported symptoms of stress and depression associated with pregnancy outcomes within the first year after referral to a tertiary recurrent pregnancy loss unit? DESIGN: Prospective cohort study with online questionnaires using the Major Depression Inventory (MDI) and Cohen's Stress Scale (PSS) at referral and after 1 year. The study was conducted between 2010 and 2014. A total of 301 women who had experienced recurrent pregnancy loss completed the first questionnaire. One year after referral, 185 women (61%) completed a follow-up questionnaire. RESULTS: A score above the threshold for major depression on the MDI at referral was not a predictor for outcome in the first pregnancy after referral; OR (95% CI) for live birth 1.71 (0.66 to 4.44), neither was increasing scores on the PSS: OR 0.98 (95% CI 0.94 to 1.02). At follow-up, women who had achieved a pregnancy resulting in a live birth had significantly lower scores on both the MDI: 13.45 (11.05) versus 11.04 (11.07); difference -2.41 (95% CI -4.60 to -0.23); and the PSS: mean 17.69 (7.59) versus 13.03 (6.83); difference -4.66 (95% CI -6.04 to -3.28), respectively. This was not the case for women who did not have a successful pregnancy. Women who experienced recurrent pregnancy loss after a successful birth were less likely to report symptoms corresponding to major depression than women who had only experienced losses (n = 7 [5%] versus 19 [12%]; P = 0.04). CONCLUSIONS: Self-reported emotional distress did not affect future chance of live birth. A live born child decreased emotional distress.

Improved sperm kinematics in semen samples collected after 2 h versus 4-7 days of ejaculation abstinence.

STUDY QUESTION: Does a short abstinence period of only 2 h yield spermatozoa with better motility characteristics than samples collected after 4-7 days? SUMMARY ANSWER: Despite lower semen volume, sperm concentration, total sperm counts and total motile counts, higher percentages of motile spermatozoa with higher velocity and progressiveness were detected in samples obtained after 2 h. WHAT IS KNOWN ALREADY: Most studies that have assessed the effect of abstinence periods on sperm motility parameters in men with a sperm concentration below 15 million/ml have detected a higher percentage of motile spermatozoa in samples obtained after short abstinence periods. Studies of men with sperm concentrations above 15 million/ml have reported significantly decreased motile sperm counts after 24 h of abstinence compared with longer abstinence periods. STUDY DESIGN, SIZE, DURATION: This study had a controlled repeated-measures design based on semen samples from 43 male partners, in couples attending for IVF treatment, who had a sperm concentration above 15 million/ml. Data were collected between June 2014 and December 2015 in the Fertility Unit of Aalborg University Hospital (Aalborg, Denmark). PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants provided a semen sample after 4-7 days of abstinence followed by another sample after only 2 h. For both ejaculates, sperm concentration, total sperm counts, motility groups and detailed kinematic parameters were assessed and compared by using the Sperm Class Analyzer (SCA) computer-aided sperm analysis system before and after density gradient selection. The laboratory's local manual method (Makler chamber) was used for comparison. MAIN RESULTS AND THE ROLE OF CHANCE: The second raw ejaculate demonstrated lower semen volume (P < 0.0001), sperm concentration (P = 0.003) and sperm counts in all motility sub-groups (P < 0.001) but higher percentages of spermatozoa with higher velocity (P < 0.01), progressiveness (P < 0.001) and hyperactivation (P < 0.001), compared with the first raw ejaculate. LIMITATIONS, REASONS FOR CAUTION: The first ejaculate in this study was also used for the IVF/ICSI treatments and therefore only patients with a semen volume ≥2 ml and concentration ≥15 million/ml were included. Further validation in large prospective randomized controlled trials, more purposely directed at normozoospermic males with partners having problems conceiving when there appears to be no female factor, is needed to confirm the potential advantage of using a second semen sample in improving fertilization and pregnancy rates in assisted reproduction. WIDER IMPLICATIONS OF THE FINDINGS: Despite the significantly lower semen volume, sperm concentration and total sperm counts in all motility sub-groups, the significantly higher percentage of spermatozoa with better motility characteristics (velocity, progressiveness and hyperactivation) in the second ejaculate, may provide and allow for a simpler and more effective selection of higher quality spermatozoa. This could prove to be an advantage for ART procedures such as intracytoplasmic sperm injection where a large number of spermatozoa is not needed. It can also be speculated that pooling two consecutive ejaculates obtained after 4-7 days and after 2 h, could be an advantage for intrauterine insemination where a large number of motile spermatozoa are needed. STUDY FUNDING/COMPETING INTEREST(S): This study was supported by internal grants from the Department of Health Science and Technology, Faculty of Medicine, Aalborg University (Aalborg, Denmark). The SCA® was provided by a grant from 'Ferring Pharmaceuticals' to Aalborg University Hospital (H.I.N). G.V.D.H. is an external senior scientific consultant to Microptic S/L (Barcelona, Spain). H.A. has provided scientific input and presentations for Microptic S/L (Barcelona, Spain) on several occasions. All other authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

Recurrent pregnancy loss: what is the impact of consecutive versus non-consecutive losses?

STUDY QUESTION: Is there a different prognostic impact for consecutive and non-consecutive early pregnancy losses in women with secondary recurrent pregnancy loss (RPL)? SUMMARY ANSWER: Only consecutive early pregnancy losses after the last birth have a statistically significant negative prognostic impact in women with secondary RPL. WHAT IS KNOWN ALREADY: The risk of a new pregnancy loss increases with the number of previous pregnancy losses in patients with RPL. Second trimester losses seem to exhibit a stronger negative impact than early losses. It is unknown whether the sequence of pregnancy losses plays a role for the prognosis in patients with a prior birth. STUDY DESIGN, SIZE, DURATION: This retrospective cohort study of pregnancy outcome in patients with unexplained secondary RPL included in three previously published, Danish double-blinded placebo-controlled trials of intravenous immunoglobulin (IvIg) conducted from 1991 to 2014. No other treatments were given. Patients with documented explained pregnancy losses (ectopic pregnancies and aneuploid miscarriages) were excluded. PARTICIPANTS/MATERIALS, SETTING, METHODS: Of the 168 patients included in the trials, 127 had secondary RPL and experienced a subsequent live birth or unexplained pregnancy loss in the first pregnancy after giving informed consent to participate in the trials (the index pregnancy). Data analyzed by multivariate analysis included the independent variables age, the number of early pregnancy losses before and after the last birth, respectively and a second trimester pregnancy loss before or after the last birth, respectively. The outcome variable was unexplained loss in the index pregnancy. MAIN RESULTS AND THE ROLE OF CHANCE: In patients with secondary RPL, both a late and each early loss before the last birth did not significantly influence the risk of a new pregnancy loss in the index pregnancy: incidence rate ratio (IRR) 1.31 (95% CI 0.62-2.77) and IRR 0.88 (95% CI 0.70-1.11), respectively. In contrast, the impact on risk of pregnancy loss conferred by a late and by each early pregnancy loss occurring after the birth was significant: IRR 2.15 (95% CI 1.57-2.94, P < 0.0001) and IRR 1.14 (95% CI 1.04-1.24, P = 0.002), respectively. LIMITATIONS, REASONS FOR CAUTION: Of the patients, 48% were treated with IvIg, which could influence the results. However, allocation to IvIg was random and prognostic variables were equally distributed in IvIg and placebo-treated patients. WIDER IMPLICATIONS OF THE FINDINGS: A birth in women with secondary RPL eradicates the negative prognostic impact of previous pregnancy losses and this finding is important for our understanding of the pathogenesis. It indicates that only consecutive pregnancy losses should count in the definition of RPL. STUDY FUNDING/COMPETING INTERESTS: There was no particular funding for this study. The authors declare that there is no conflict of interest. TRIAL REGISTRATION NUMBER: Not applicable for two of the included randomized controlled trials. For the last trial: Clinical.Gov NCT00722475.

Placental magnetic resonance imaging T2* measurements in normal pregnancies and in those complicated by fetal growth restriction.

OBJECTIVES: The magnetic resonance imaging (MRI) variable transverse relaxation time (T2*) depends on multiple factors, one important one being the presence of deoxyhemoglobin. We aimed to describe placental T2* measurements in normal pregnancies and in those with fetal growth restriction (FGR). METHODS: We included 24 normal pregnancies at 24-40 weeks' gestation and four FGR cases with an estimated fetal weight below the 1(st) centile. Prior to MRI, an ultrasound examination, including Doppler flow measurements, was performed. The T2* value was calculated using a gradient echo MRI sequence with readout at 16 different echo times. In normal pregnancies, repeat T2* measurements were performed and interobserver reproducibility was assessed in order to estimate the reproducibility of the method. Placental histological examination was performed in the FGR cases. RESULTS: The method was robust regarding the technical and interobserver reproducibility. However, some slice-to-slice variation existed owing to the heterogeneous nature of the normal placenta. We therefore based T2* estimations on the average of two slices from each placenta. In normal pregnancies, the placental T2* value decreased significantly with increasing gestational age, with mean ± SD values of 120 ± 17 ms at 24 weeks' gestation, 84 ± 16 ms at 32 weeks and 47 ± 17 ms at 40 weeks. Three FGR cases had abnormal Doppler flow, histological signs of maternal hypoperfusion and a reduced T2* value (Z-score < -3.5). In the fourth FGR case, Doppler flow, placental histology and T2* value (Z-score, -0.34) were normal. CONCLUSIONS: The established reference values for placental T2* may be clinically useful, as T2* values were significantly lower in FGR cases with histological signs of maternal hypoperfusion. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.