Henriette Svarre Nielsen

Multifactorial Etiology of Recurrent Miscarriage and Its Scientific and Clinical Implications

A considerable proportion of recurrent miscarriage (RM) cases are caused by recurrent chromosomally abnormal conceptions. However, in younger patients and patients with multiple miscarriages, maternal causes seem to dominate. No single biomarker with a high predictive value of maternally caused RM has been identified. Non-genetic biomarkers in RM may not reflect conditions in the pregnant uterus and we rarely know whether they are causes or consequences of miscarriage. Studies of genetic biomarkers are probably the best way to reveal the pathophysiological mechanisms behind RM. Epidemiological and genetic studies suggest that RM due to maternal causes has a multifactorial background. The risk of RM in each patient is probably determined by the interaction of many genetic variants and environmental factors but only few of these have so far been identified. The genetic biomarkers for RM can probably be classified into three groups: (1) variants associated with excessive inflammatory responses and autoimmunity; (2) variants of importance for insulin and androgen sensitivity and turn-over, and (3) variants associated with thrombophilia. Identification of these markers will require whole genome association studies comprising thousands of individuals. Acknowledgement of the multifactorial background for RM has important implications for the management of patients in clinical practice.

Vasoactive intestinal polypeptide induces per1 and per2 gene expression in the rat suprachiasmatic nucleus late at night.

Circadian rhythms in behaviour and physiology generated by the suprachiasmatic nucleus (SCN) are entrained to the environmental light/dark cycle via the retinohypothalamic tract. How light is able to adjust the endogenous rhythm is not fully understood, but induction of the two clock genes per1 and per2 in the SCN is believed to be important for the adjustment. Recently, it was shown that vasoactive intestinal polypeptide (VIP), a neurotransmitter found in light‐responsive cells of the SCN, is able to phase shift the circadian rhythm similar to light. In the present study we show by means of an in vitro brain slice model and quantitative in situ hybridization histochemistry that VIP induces both per1 and per2 gene expression in the SCN during late subjective night (CT19). The signalling pathways responsible for the VIP signalling to the clock were investigated using inhibitors of protein kinase A and phospholipase C mediated signalling. Our results demonstrate that both pathways are involved in VIP induced per gene expression and suggest that VIP is important for light‐induced phase shift late at night.

Expression of pituitary adenylate cyclase activating polypeptide (PACAP) in the postnatal and adult rat cerebellar cortex

IN adult rat, immunostaining for pituitary adenylate cyclase activating polypeptide (PACAP) was demonstrated in the soma and dendrites of Purkinje cells and in nerve fibres around granule cells. PACAP in the Purkinje cells was confirmed by the presence of mRNA. The concentration of PACAP-38 was high after birth and declined to adult levels within a few weeks. At birth PACAP-immunoreactive nerve fibres and a few cells were present in the Purkinje cell layer, but already at postnatal day 7 an adult PACAP immunostaining pattern was found. The findings suggest that PACAP could be a neurotransmitter in the adult cerebellum and provide a morphological correlate for the reported in vitro anti-apoptotic PACAP effects on cerebellar granule cells from 1-week-old rats.

Fear of childbirth predicts postpartum depression: A population-based analysis of 511 422 singleton births in Finland

Objectives To study how reproductive risks and perinatal outcomes are associated with postpartum depression treated in specialised healthcare defined according to the International Classification of Diseases (ICD)-10 codes, separately among women with and without a history of depression. Design A retrospective population-based case–control study. Setting Data gathered from three national health registers for the years 2002−2010. Participants All singleton births (n=511 422) in Finland. Primary outcome measures Prevalence of postpartum depression and the risk factors associated with it. Results In total, 0.3% (1438 of 511 422) of women experienced postpartum depression, the prevalence being 0.1% (431 of 511 422) in women without and 5.3% (1007 of 18 888) in women with a history of depression. After adjustment for possible covariates, a history of depression was found to be the strongest risk factor for postpartum depression. Other strong predisposing factors for postpartum depression were fear of childbirth, caesarean birth, nulliparity and major congenital anomaly. Specifically, among the 30% of women with postpartum depression but without a history of depression, postpartum depression was shown to be associated with fear of childbirth (adjusted OR (aOR 2.71, 95% CI 1.98 to 3.71), caesarean birth (aOR 1.38, 95% CI 1.08 to 1.77), preterm birth (aOR 1.65, 95% CI 1.08 to 2.56) and major congenital anomaly (aOR 1.67, 95% CI 1.15 to 2.42), compared with women with no postpartum depression and no history of depression. Conclusions A history of depression was found to be the most important predisposing factor of postpartum depression. Women without previous episodes of depression were at an increased risk of postpartum depression if adverse events occurred during the course of pregnancy, especially if they showed physician-diagnosed fear of childbirth.

Association of HY-restricting HLA class II alleles with pregnancy outcome in patients with recurrent miscarriage subsequent to a firstborn boy

Healthy females, pregnant with a boy, generate immune responses against male-specific minor histocompatibility (HY) antigens. The clinical importance of these responses is evident in stem cell transplantation. Birth of a boy prior to a series of miscarriages reduces the chance of a subsequent live birth. This study explores the putative impact of known HY-presenting HLA alleles on future pregnancy outcome in women with at least three consecutive miscarriages following a birth [secondary recurrent miscarriage (SRM)]. HLA-A, -B, -DRB1, DRB3-5 and DQB1 genotyping was performed in 358 SRM patients and in 203 of their children born prior to the miscarriages. The subsequent live birth in women with boys prior to the miscarriages compared with girls is lower in women with HY-restricting HLA class II alleles [odds ratio (OR): 0.17 (0.1-0.4), P = 0.0001]. One HY-restricting HLA class II allele in women with firstborn boys significantly reduces the chances of a live birth [OR: 0.46 (0.2-0.9), P = 0.02]. Two HY-restricting HLA class II alleles further reduced this chance [OR: 0.21 (0.1-0.7), P = 0.02]. HY-restricting HLA class II did not reduce the chances of a live birth in SRM women with firstborn girls. HY-restricting HLA class II alleles are associated with a decreased chance of a live birth in SRM women with firstborn boys. These findings strongly indicate an aberrant maternal immune reaction against fetal HY-antigens in SRM. The results may shed light on the as-yet unknown immunological causes of SRM and may help understand the successful maternal acceptance of the fetal semi-allograft.

Future directions of failed implantation and recurrent miscarriage research

Recurrent implantation failure is today the major reason for women completing several IVF/intracytoplasmic sperm injection attempts without having achieved a child, and is probably also the explanation for many cases of unexplained infertility. Most causes of recurrent miscarriage are still poorly elucidated, but from a theoretical point of view recurrent implantation failure and recurrent miscarriage are suggested to have partly overlapping causes. Recent research has indeed documented that both syndromes can be caused by the same embryonic chromosomal abnormalities and the same maternal endocrine, thrombophilic and immunological disturbances. Consequently, many treatments attempting to normalize these abnormalities have been tested or are currently used in women with both recurrent implantation failure and recurrent miscarriage. However, no treatment for the two syndromes is at the moment sufficiently documented to justify its routine use. In this review, an overview is given regarding present knowledge about causes that may be common for recurrent implantation failure and recurrent miscarriage, and suggestions are put forward for future research that may significantly improve understanding and treatment options for the syndromes.

A genome-wide scan in affected sibling pairs with idiopathic recurrent miscarriage suggests genetic linkage

Previously, siblings of patients with idiopathic recurrent miscarriage (IRM) have been shown to have a higher risk of miscarriage. This study comprises two parts: (i) an epidemiological part, in which we introduce data on the frequency of miscarriage among 268 siblings of 244 patients with IRM and (ii) a genetic part presenting data from a genome-wide linkage study of 38 affected sibling pairs with IRM. All IRM patients (probands) had experienced three or more miscarriages and affected siblings two or more miscarriages. The sibling pairs were genotyped by the Affymetrix GeneChip 50K XbaI platform and non-parametric linkage analysis was performed via the software package Merlin. We find that siblings of IRM patients exhibit a higher frequency of miscarriage than population controls regardless of age at the time of pregnancy. We identify chromosomal regions with LOD scores between 2.5 and 3.0 in subgroups of affected sibling pairs. Maximum LOD scores were identified in four occurrences: for rs10514716 (3p14.2) when analyzing sister-pairs only; for rs10511668 (9p22.1) and rs341048 (11q13.4) when only analyzing families where the probands have had four or more miscarriages; and for rs10485275 (6q16.3) when analyzing one sibling pair from each family only. We identify no founder mutations. Concluding, our results imply that IRM patients and their siblings share factors which increase the risk of miscarriage. In this first genome-wide linkage study of affected sibling pairs with IRM, we identify regions on chromosomes 3, 6, 9 and 11 which warrant further investigation in order to elucidate their putative roles in the genesis of IRM.

Risk factors for and perinatal outcomes of major depression during pregnancy: a population-based analysis during 2002-2010 in Finland

Objectives To identify risk factors for and the consequences (several adverse perinatal outcomes) of physician-diagnosed major depression during pregnancy treated in specialised healthcare. Design A population-based cross-sectional study. Setting Data were gathered from Finnish health registers for 1996–2010. Participants All singleton births (n=511 938) for 2002–2010 in Finland. Primary outcome measures Prevalence, risk factors and consequences of major depression during pregnancy. Results Among 511 938 women, 0.8% experienced major depression during pregnancy, of which 46.9% had a history of depression prior to pregnancy. After history of depression, the second strongest associated factor for major depression was fear of childbirth, with a 2.6-fold (adjusted OR (aOR=2.63, 95% CI 2.39 to 2.89) increased prevalence. The risk profile of major depression also included adolescent or advanced maternal age, low or unspecified socioeconomic status (SES), single marital status, smoking, prior pregnancy terminations, anaemia and gestational diabetes regardless of a history of depression. Outcomes of pregnancies were worse among women with major depression than without. The contribution of smoking was substantial to modest for small-for-gestational age newborn (<−2 SD below mean birth), low birth weight (<2500 g), preterm birth (<37 weeks) and admission to neonatal intensive care associated with major depression, whereas SES made only a minor contribution. Conclusions Physician-diagnosed major depression during pregnancy was found to be rare. The strongest risk factor was history of depression prior to pregnancy. Other associated factors were fear of childbirth, low SES, lack of social support and unhealthy reproductive behaviour such as smoking. Outcomes of pregnancies were worse among women with major depression than without. Smoking during pregnancy made a substantial to modest contribution to adverse outcomes associated with depression during pregnancy.

The presence of HLA-antibodies in recurrent miscarriage patients is associated with a reduced chance of a live birth

Anti-paternal HLA-antibodies are considered a harmless phenomenon during most pregnancies, whereas their role in recurrent miscarriage (RM) patients is disputed. In contrast to primary RM, patients with secondary RM have carried a fetus to term pregnancy prior to a series of miscarriages, which increases the chance that allogeneic fetal cells appear in the maternal circulation. This study investigates the frequency of HLA-antibodies in secondary RM, primary RM patients and parous controls and analyzes whether the presence of HLA-antibodies in early pregnancy is associated with pregnancy outcome. Sera from women with secondary RM (n=56), primary RM (n=13) and parous controls (n=24) were tested for HLA-antibodies using an ELISA assay and complement dependent cytotoxicity. Samples were taken at gestational week 4-5 in 62 (90%) of the patients. HLA-antibodies were significantly more frequent in secondary RM patients with a boy prior to the miscarriages (62%) compared to secondary RM patients with a firstborn girl (29%, p=0.03), primary RM patients (23%, p=0.02) and parous controls (25%, p=0.005). Forty-one percent of HLA-antibody positive pregnant RM patients had a live birth compared to 76% of HLA-antibody negative RM patients, p=0.006 (adjusted OR: 0.22 (0.07-0.68), p=0.008). In conclusion, HLA-antibodies are significantly more frequent in secondary RM patients with a firstborn boy than in other RM patients and controls. The presence of these antibodies in early pregnancy is associated with a reduced chance of a live birth. Further exploring this association may increase our understanding of maternal acceptance of the fetal allograft.

Expression of melanopsin during development of the rat retina

There is accumulating evidence that the new opsin-like protein, melanopsin, in adult rodents functions as non-visual photoreceptor. Here we report using immunohistochemistry and in situ hybridisation that melanopsin during rat retinal development is expressed already at prenatal day 18 in cells of the inner neuroblast layer. Perinatally the melanopsin positive cells increase in number and migrate towards the ganglion cell layer. During early postnatal development a melanopsin immunoreactive dendritic network is formed in the inner plexiform layer. Melanopsin is exclusively expressed in PACAP-containing cells which in adults become the retinal ganglion cells constituting the retinohypothalamic tract. The early expression of melanopsin argues for a photoreceptor role in the developing retinohypothalamic tract which is functional as early as the first day after birth.