Dydrogesterone in the reduction of recurrent spontaneous abortion

One hundred and eighty Women with a history of recurrent, unexplained spontaneous abortion (mean 3.5 abortions) were randomised to receive oral dydrogesterone (10 mg b.i.d.), intramuscular human chorionic gonadotrophin (hCG; 5000 IU every 4 days) or no additional treatment (controls). Treatment was started as soon as possible after confirmation of pregnancy and continued until the 12th gestational week. All women received standard supportive care. Abortions were significantly (p ≤ 0.05) less common in the dydrogesterone group (13.4%) than in the control group (29%); there were no statistically significant differences between the hCG group and the control group. There were no differences between the groups with respect to pregnancy complications or congenital abnormalities. In conclusion, hormonal support with dydrogesterone can increase the chances of a successful pregnancy in women with a history of recurrent spontaneous abortion.     

The role of dydrogesterone in recurrent (habitual) abortion

The published evidence regarding the administration of dydrogesterone in the treatment of habitual abortion is summarised in this review. Habitual abortion is defined as the loss of three or more consecutive pregnancies without known maternal or foetal pathology. The immunology of early pregnancy seems to determine the rejection or non-rejection of the allogenic embryo. When peripheral mononuclear cells from recurrent aborters are incubated with progesterone or dydrogesterone in vitro, T-helper (Th)2 cytokines such as interleukin (IL)-4 and IL-6 markedly increase whereas the Th1 cytokine interferon-γ decreases. Additionally, both progesterone and dydrogesterone are thought to inhibit the activity of natural killer cells at the foeto-maternal interface in humans. Progesterone-induced blocking factor (PIBF) mediates the immunological effects of progesterone and dydrogesterone in pregnancy. It affects various phases of the maternal immune response involving both the cellular and humoral immune system, exerts anti-abortive effects and inhibits the release of arachidonic acid. It also favours the production of so-called asymmetric, pregnancy-protecting antibodies. In rodents, blockade of this factor results in the termination of pregnancy and in women considerably lower levels are found in those with threatened abortion or pre-term labour. In order to draw final conclusions as to the usefulness of dydrogesterone in women with a history of recurrent miscarriage, further controlled, blinded, randomised clinical trials are needed.     

Plasma copper concentrations in pathological pregnancies.

Copper is an essential element required for the formation of many enzymes with important roles in the human body. During pregnancy, the maternal serum copper concentration is increased due to the higher levels of ceruloplasmin that are the result of elevated oestrogen levels. The aim of this work was to investigate maternal plasma copper concentrations in relation to various pathological conditions during pregnancy. A total of 319 maternal plasma samples were analysed: 103 taken from women in the first trimester, 73 in the second trimester, 99 in the third trimester of pregnancy and 44 at delivery. The plasma concentration of copper during each trimester of normal pregnancy was taken as a reference value. Group comparisons performed by analysis of variance (ANOVA) followed by Dunnett test indicated substantially lower plasma concentrations of copper in pathological conditions diagnosed during the first trimester of pregnancy (spontaneous abortion, threatened abortion, missed abortion and blighted ovum). No significant differences in maternal plasma blood copper concentrations were found in pathological conditions (threatened abortion, threatened preterm delivery and pyelonephritis) diagnosed in the second trimester of pregnancy. Significant differences in plasma copper concentrations were found in the third trimester, for which finding the Dunnett test indicated the cholestasis group to be responsible. Except for twin pregnancy, a tendency to higher plasma copper concentrations, however not statistically significant, was observed in other pathological conditions during the third trimester (gestosis, intrauterine growth retardation, preterm labour).     

Prognosis of subsequent pregnancies after recurrent spontaneous abortion in first trimester.

The outcome of subsequent pregnancies was studied in 24 women with a history of three or more consecutive spontaneous abortions in the first trimester. Twenty one of the women agreed to forgo active treatment during the study period and three received progestogens or surgical intervention. As the outcome of their first pregnancy after recurrent abortion 18 of the 24 women delivered a liveborn infant after 28 weeks or more. Of all 49 pregnancies in the untreated group during the study, 10 ended in abortion. Only one woman in the study failed to achieve a live birth. Except in exceptional cases encouraging women with recurrent abortion to keep trying for a successful outcome is just as effective as currently recommended treatments.     

地屈孕酮联合口服黄体酮胶丸对黄体功能不全先兆流产患者血清抑制素A、性激素的影响

摘要 目的：探讨地屈孕酮联合口服黄体酮胶丸对黄体功能不全先兆流产患者血清抑制素A、性激素的影响。方法：选择2018年9月到2020年9月在我院接受治疗的125例黄体功能不全先兆流产患者,采用随机数表法分为试验组（n=63）和对照组（n=62）。对照组给予黄体酮胶丸治疗,试验组在对照组的基础上给予地屈孕酮治疗。比较两组临床疗效、抑制素A、雌二醇（E₂）、孕酮（P）、人绒毛膜促性腺激素（HCG）、临床症状改善情况、妊娠结局及不良反应发生情况。结果：治疗后,两组总有效率比较差异显著（P<0.05）;治疗前,试验组和对照组血清抑制素A、E2、P、HCG比较无显著差异;治疗后试验组和对照组血清抑制素A、E₂、P、HCG随着时间的推移而升高,且试验组均高于对照组,差异显著（P<0.05）;试验组止血时间、腹痛改善时间及腰痛改善时间均显著低于对照组,差异显著（P<0.05）;试验组保胎成功率、新生儿体质量及新生儿Apgar评分均显著高于对照组,差异显著（P<0.05）;两组不良反应总发生率分别为7.94%、9.68%（P>0.05）。结论：在黄体功能不全先兆流产患者中应用地屈孕酮联合口服黄体酮胶丸效果显著,可能与其可有效改善血清抑制素A、性激素水平有关,且不增加不良反应。     

Medroxyprogesterone acetate therapy in early pregnancy has no apparent fetal effects

Medroxyprogesterone acetate (MPA; Provera) was given orally to 449 women from the 5th to 7th week of pregnancy until at least the 18th week. Data are recorded from two treatment groups (recurrent abortion and threatened abortion) and are compared to a matched series. A total of 1,016 pregnancies are included in the study, and all patients were recruited from a subfertile population conceiving from a range of infertility treatments. Early pregnancy wastage was high throughout the groups and was significantly elevated (43%; P less than .001) in those women who had vaginal bleeding in early pregnancy. The study focuses on the question of potential teratogenicity of progestagens administered in the first trimester. There were 15/366 (4.1%) infants with congenital abnormalities in the MPA-treated group and 15/428 in the untreated group (3.5%). The difference was not significant, and MPA is considered to have no embryopathic risk, nor is it likely to retain an abnormal fetus that might otherwise abort. It appears that MPA is a safe drug to use in pregnancy although the question of efficacy has not been addressed in this report. Considering other recent negative epidemiologic studies with regard to teratogenicity, we add to the conclusion that MPA cannot be demonstrated to have a measurable teratogenic risk and certainly does not present a risk for congenital heart disease and limb reduction defects.     

Randomised controlled trial of aspirin and aspirin plus heparin in pregnant women with recurrent miscarriage associated with phospholipid antibodies (or antiphospholipid antibodies)

OBJECTIVE: To determine whether treatment with low dose aspirin and heparin leads to a higher rate of live births than that achieved with low dose aspirin alone in women with a history of recurrent miscarriage associated with phospholipid antibodies (or antiphospholipid antibodies), lupus anticoagulant, and cardiolipin antibodies (or anticardiolipin antibodies). DESIGN: Randomised controlled trial. SETTING: Specialist clinic for recurrent miscarriages. SUBJECTS: 90 women (median age 33 (range 22-43)) with a history of recurrent miscarriage (median number 4 (range 3-15)) and persistently positive results for phospholipid antibodies. INTERVENTION: Either low dose aspirin (75 mg daily) or low dose aspirin and 5000 U of unfractionated heparin subcutaneously 12 hourly. All women started treatment with low dose aspirin when they had a positive urine pregnancy test. Women were randomly allocated an intervention when fetal heart activity was seen on ultrasonography. Treatment was stopped at the time of miscarriage or at 34 weeks'' gestation. MAIN OUTCOME MEASURES: Rate of live births with the two treatments. RESULTS: There was no significant difference in the two groups in age or the number and gestation of previous miscarriages. The rate of live births with low dose aspirin and heparin was 71% (32/45 pregnancies) and 42% (19/45 pregnancies) with low dose aspirin alone (odds ratio 3.37 (95% confidence interval 1.40 to 8.10)). More than 90% of miscarriages occurred in the first trimester. There was no difference in outcome between the two treatments in pregnancies that advanced beyond 13 weeks'' gestation. Twelve of the 51 successful pregnancies (24%) were delivered before 37 weeks'' gestation. Women randomly allocated aspirin and heparin had a median decrease in lumbar spine bone density of 5.4% (range -8.6% to 1.7%). CONCLUSION: Treatment with aspirin and heparin leads to a significantly higher rate of live births in women with a history of recurrent miscarriage associated with phospholipid antibodies than that achieved with aspirin alone.     

The progesterone derivative dydrogesterone abrogates murine stress-triggered abortion by inducing a Th2 biased local immune response

Stress is known to induce abortions in mice and humans, putatively via increased levels of abortogenic Th1 cytokines and a decrease of progesterone. Adequate levels of progesterone exert an antiabortive response through binding to the progesterone-receptor, which induces the release of progesterone-induced blocking factor (PIBF) from lymphocytes. PIBF is highly pregnancy-protective by induction of a Th2 biased immune activity. The aim of this study was to investigate the effect of the progesterone derivative dydrogesterone (6-dehydro-retroprogesterone) in stress-triggered murine abortion. DBA/2J-mated CBA/J female mice were randomized in different groups: two groups were treated with different dydrogesterone dosages in a single injection before exposure to sound stress on Day 5 of pregnancy, one group was exposed to stress without dydrogesterone treatment, the fourth group received no stress and no dydrogesterone. On gestation Day 13, a highly elevated abortion rate was detected in stressed mice compared to control mice. Stressed animals presented lower levels of progesterone and PIBF in plasma and a reduced staining intensity of progesterone receptor at the feto-maternal interface. Injection of dydrogesterone abrogated the effect of stress on the abortion rate. Further, dydrogesterone increased levels of plasma PIBF in stressed mice, but did not affect progesterone levels. Interestingly, dydrogesterone dramatically increased the percentage of IL-4 positive decidual immune cells in stressed mice. Our data suggest that dydrogesterone abrogates stress-triggered abortion by inducing a Th2 biased local immune response.     

Alpha-fetoprotein in Abortion

The clinical value of maternal serum alpha-fetoprotein (AFP) as a guide to the outcome of threatened abortion was assessed. After the thirteenth week of gestation, abortion occurred more frequently (10/12) in women with abnormal serum AFP levels than in those (2/12) whose AFP concentrations were within the normal range. Low levels were present in women with blighted ovum and high concentrations were associated with intrauterine fetal death. In legal first and second trimester abortions, the circulating maternal AFP levels in postabortion samples were often higher than before abortion, irrespective of whether abortion was performed instrumentally or induced with prostaglandins. Maternal serum AFP levels provide a new means for prediction of the outcome of threatened abortion.     

血清P、β-HCG联合检测预测和治疗先兆流产的临床研究

目的：探讨血清孕酮与B-HCG联合检测在预测早期先兆流产预后及其治疗的临床价值。方法：对340例早期先兆流产患者血清P与B-HCG进行检测,并与追踪到的妊娠结局进行分析。结集：血清P值〉25ng／ml、血β-HCG〉50mIU／ml患者66例占19．4％,经绝对卧床休息,未用药治疗,均胚胎发育正常;血清P值在15．94-25ng／ml、血β-HCG10-50mlU／ml患者170例占50％,经口服黄体酮与HCG针保胎治疗后均胚胎发育正常;血清P值〈15．94ng／ml、血β-HCG〈10mIU／ml患者78例占22．9％,终止妊娠者均可见清除宫内组织物中几乎不见新鲜绒毛并伴有不同程度的陈旧性出血;血清孕酮与β-HCG上升不同步患者26例占7．6%,均最终难免流产。结论：联合检测血清孕酮与β-HCG可以预测先兆流产患者妊娠结局,对于指导治疗具有重要的临床价值,既避免不必要的药物干预及经济负担,又能起到提高保胎治疗的成功率。绒毛膜促性腺激素配伍口服天然黄体酮治疗由黄体功能不全引发的早期先兆流产,均能改善先兆流产患者的预后,且对母儿无不良影响,安全有效。     

A retrospective study of 932 second trimester terminations using gemeprost (16,16 dimethyl-trans delta 2 PGE1 methyl ester).

A retrospective study of 932 second trimester terminations between 12-27 weeks gestation was carried out to determine the efficacy of gemeprost for second trimester termination. A single course of 5 x 1 mg gemeprost pessaries was administered every three hours. If abortion had not occurred after the first course of pessaries, a further course of 5 x 1 mg pessaries was administered. Intravenous oxytocin was administered after 36 hours if abortion had not occurred. Eighty per cent and ninety five per cent of patients aborted within 24 and 48 hours respectively. Of the remaining 5 per cent of women, 3 per cent aborted with escalating doses of oxytocin. In the remaining 18 (2 per cent) women, the pregnancies were electively terminated with an alternative method. The median induction-abortion interval was 18.0 hours and 15.0 hours in nulliparous and parous women respectively (P less than 0.0001). The number of pessaries required to induce abortion was not influenced by parity. Significantly more parous women bled more than 500 ml. The incidence of pelvic sepsis (0.1 per cent) and cervical tear (0.1 per cent) was low. Twenty six per cent of women had diarrhoea and 23 per cent vomited following administration of prostaglandin. This study confirmed the efficacy of gemeprost for second trimester termination of pregnancy. This method of termination is safe, non-invasive, simple and has a low complication rate.     

Determination of selected coagulation parameters in induced abortion by means of 15-methyl-PGF2 alpha]

There were accomplished investigations about changes of bleeding and recalcification time, platelet count, levels of heat-fibrin, prothrombin, partial thromboplastin time, platelet adhesiveness and heparinocytes at 10 women during induction of therapeutic abortion by use of intramuscular injections of 15-methyl-PGF2 alpha in the first and second trimester of pregnancy. The studies were performed before treatment, 30 minutes, 4 and 8 hours after beginning 15-methyl-PGF2 alpha-administration, 2 hours after expulsion of product of conception and 24 hours after first injection. The following investigations showed statistical significant changes: Prothrombin decreased during treatment with 15-methyl-PGF2 alpha and did not obtain the starting value 24 hours after first injection. Platelet count showed an equal attitude. The heparinocytes showed a continuous falling off up to 2 hours after termination the pregnancy. A significant ascent was noticed 24 hours after first investigation. The results of studies did not indicate a strong injury of coagulation system. They support the positive estimate for induction of therapeutic abortion with 15-methyl-PGF2 alpha in the first and second trimester of pregnancy.     

Effects of legal termination on subsequent pregnancy.

Two hundred and eleven patients who had undergone vaginal termination and were pregnant again were investigated; 43-2% had become pregnant within one year of termination. The overall fetal loss in the 211 patients was 17-5% compared with 7-5% in a group matched for parity but consisting of patients who were pregnant after a spontaneous abortion. Altogether 4-3% of pregnancies after legal abortion ended as first trimester abortions, 8-5% as second trimester abortions, and 13-7% in premature delivery. Among 11 women whose cervices had been lacerated at the time of legal termination the fetal loss in subsequent pregnancy was 45-5%, and only one pregnancy went beyond 36 weeks. Routine Shirodkar suture may be beneficial when the cervix is known to have been damaged at legal abortion. Several patients had asked that their general practitioner should not be told of their termination, and such patients may not admit their termination during a subsequent pregnancy, which could thus be jeopardised. No evidence was found to suggest that infants of patients with a history of legal termination are small for dates.     

血清妊娠相关血浆蛋白A在诊断异常妊娠中的临床意义

目的:探讨血清妊娠相关血浆蛋白A(PAPP-A)在诊断异常妊娠中的临床意义,分析其与异常妊振的关系。方法:选取299例5~13周的正常早孕妇为正常早孕组,同期选取稽留流产86例,先兆流产54例,异位妊娠76例为异常妊娠组,用酶联免疫吸附试验(ELASA)测定两组受试者的血清PAPP-A水平,分析两组受试者各个孕周内的血清PAPP-A水平的差异。结果:稽留流产孕妇在各个孕周内(9~13周)的血清PAPP-A水平显著低于同孕周内正常早孕孕妇(t值分别为9.500,8.113,3.511,9.538,8.504,P值均0.05);稽留流产孕妇总的平均血清PAPP-A水平亦低于常早孕孕妇(t=3.651,P值均0.05);异位妊娠孕妇在各个孕周内(9~13周)的血清PAPP-A水平显著低于同孕周内正常早孕孕妇(t值分别为7.976,9.030,9.941,11.625,14.079,12.569,P值均0.05),异位妊娠孕妇总的平均血清PAPP-A水平亦低于常早孕孕妇(t=28.168,P值均0.05);先兆流产孕妇(除孕8周)与正常早孕妊娠血清PAPP-A水平比较无显著统计学意义。结论:血清PAPP-A水平在异常妊娠如异位妊娠、稽留流产中显著降低,可作为诊断异位妊娠、稽留流产及先兆流产辅助诊断的生物学指标。     

Development of a vaginal gel containing 9-deoxo-16,16-dimethyl-9-methylene PGE2 for cervical dilatation and pregnancy termination

A stable hydrophilic gel for vaginal administration containing 9-deoxo-16,16-dimethyl-9-methylene PGE2 (9-methylene PGE2) was developed and its clinical usefulness for preoperative cervical dilatation and for termination of first and second trimester pregnancy evaluated in 521 pregnant patients admitted to the hospital for therapeutic abortion. Following vaginal administration of 3 mg of 9-methylene PGE2 gel a peak plasma level of between 3.5 and 10 ng/ml was found 3 to 6 hours following treatment. The "bioavailability" of the drug was in the order of 25-30%. 9-methylene PGE2 was found to be equally effective as 1 mg Cervagem for preoperative cervical dilatation. With a pretreatment period of 3 hours side effects were rare with both compounds. If the pretreatment period was extended to 12 hours the degree of cervical dilatation, but also the frequency of side effects increased significantly. Repeated administration of 9-methylene PGE2 was found to be effective (96% complete abortion) in terminating very early pregnancy provided the total dose was 10 mg or more. During second trimester the minimum effective dose was 4.5 mg of the compound repeated every fourth hour. The results of the present study have shown that with the new gel formulation the amount of 9-methylene PGE2 needed to terminate first and second trimester pregnancy was approximately ten times less in comparison with the previously used lipid base suppositories. The treatment was also associated with a low frequency of side effects.     

Properties of chromatin of peripheral blood lymphocytes in women with threatened abortion

The authors studied the properties of peripheral blood lymphocyte chromatin from donors (non-pregnant women), from women with normal pregnancy and during threatened abortion. Using three independent cytochemical methods that characterize the DNA accessibility for acridine orange and 3H-actinomycin D and the presence in histones of free amino groups, it has been established that lymphocyte chromatin from women during threatened abortion is repressed to a greater degree than in those with normal pregnancy. The data presented demonstrate the prospectiveness of the use of the cytochemical tests for chromatin properties with a purpose of diagnosing whether the pregnancy will be full-term and treatment control.     

Influence of past reproductive performance on risk of spontaneous abortion.

OBJECTIVE--To investigate the incidence of spontaneous abortion in a population of women in order to establish their risk of spontaneous abortion and the obstetric factors predisposing to it. DESIGN--Prospective study of women recruited by radio and poster appeal and from hospital outpatient clinics. SETTING--English provincial community. PATIENTS--630 Women from the general population intending to become pregnant. INTERVENTIONS--The viability of the pregnancy was assessed by abdominal ultrasonography before completion of the eighth week, and the assessment was repeated if vaginal bleeding occurred. MAIN OUTCOME MEASURE--Spontaneous abortion or live births in women with or without a previous history of spontaneous abortion. RESULTS--The overall incidence of clinically recognisable spontaneous abortion before 20 weeks of gestation was 12% (50/407 pregnancies). The risk of spontaneous abortion in each category of patient was classified with respect to the patient''s past reproductive performance and found to be influenced greatly by her previous obstetric history. In primigravidas and women with a history of consistently successful pregnancies the incidences of abortion were low (5% (4/87) and 4% (3/73) respectively), whereas women with only unsuccessful histories had a much greater risk of aborting the study pregnancy (24% (24/98)), even when their sole pregnancy had ended in abortion (20% (12/59)). The outcome of the last pregnancy also influenced the outcome of the study pregnancy; only 5% of women (5/95) whose previous pregnancy had been successful aborted, whereas the incidence of loss of pregnancy among women whose last pregnancy had aborted was 19% (40/214). CONCLUSIONS--A knowledge of the patient''s reproductive history is essential for the clinical assessment of her risk of spontaneous abortion. As the most important predictive factor for spontaneous abortion is a previous abortion, the outcome of a woman''s first pregnancy has profound consequences for all subsequent pregnancies.     

Does suppressing luteinising hormone secretion reduce the miscarriage rate? Results of a randomised controlled trial.

OBJECTIVE--To determine whether prepregnancy pituitary suppression of luteinising hormone secretion with a luteinising hormone releasing hormone analogue improves the outcome of pregnancy in ovulatory women with a history of recurrent miscarriage, polycystic ovaries, and hypersecretion of luteinising hormone. DESIGN--Randomised controlled trial. SETTING--Specialist recurrent miscarriage clinic. SUBJECTS--106 women with a history of three or more consecutive first trimester miscarriages, polycystic ovaries, and hypersecretion of luteinising hormone. INTERVENTIONS--Women were randomised before conception to receive pituitary suppression with a luteinising hormone releasing hormone analogue followed by low dose ovulation induction and luteal phase progesterone (group 1) or were allowed to ovulate spontaneously and then given luteal phase progesterone alone or luteal phase placebo alone (group 2). No drugs were prescribed in pregnancy. MAIN OUTCOME MEASURES--Conception and live birth rates over six cycles. RESULTS--Conception rates in the pituitary suppression and luteal phase support groups were 80% (40/50 women) and 82% (46/56) respectively (NS). Live birth rates were 65% (26/40) and 76% (35/46) respectively (NS). In the luteal phase support group there was no difference in the outcome of pregnancy between women given progesterone and those given placebo pessaries. Live birth rates from an intention to treat analysis were 52% (26/50 pregnancies) in the group given pituitary suppression and 63% (35/56) in the controls (NS). CONCLUSIONS--Prepregnancy suppression of high luteinising hormone concentrations in ovulatory women with recurrent miscarriage and hypersecretion of luteinising hormone does not improve the outcome of pregnancy. The outcome of pregnancy without pituitary suppression is excellent.     

Prostaglandin-induced pregnancy termination: further studies using gemeprost (16,16 dimethyl-trans-delta 2-PGE1 methyl ester) vaginal pessaries in the early second trimester

The use of gemeprost (16,16 dimethyl-trans-delta 2-PGE1 methyl ester) vaginal pessaries for the termination of pregnancy in the early second trimester has been further investigated. Of 113 women between 12 and 16 weeks gestation, 93 (82%) aborted within 24 hours of the administration of 4.4 +/- 0.1 1 mg gemeprost pessaries. The mean induction-abortion interval was 881 +/- 31 minutes. Successful abortion was achieved in 16 of the remaining 20 women after a second course of gemeprost pessaries without the need for oxytocin supplementation. There were no serious complications. Crampy abdominal pain and vaginal bleeding started after 275 and 756 minutes respectively. Twenty-two (19%) patients did not require pain relief during treatment, but 90 (80%) required parenteral opiates. Vomiting and diarrhoea occurred in 16 (14%) and 23 (20%) cases respectively. The safe induction of therapeutic abortion in 96% of women using vaginal prostaglandin alone offers an acceptable alternative to surgical evacuation in the early second trimester.     

Epigenetic status of imprinted genes in placenta during recurrent pregnancy loss

An analysis of differential methylation of 47 imprinted genes in placenta tissues of spontaneous abortions at the first trimester of pregnancy from women with recurrent pregnancy loss or with one sporadic abortion was performed using the DNA-microarray approach. We showed that epimutations of the imprinted genes were registered significantly more often in abortions from women with recurrent miscarriage in contrast to the embryos from women with sporadic pregnancy loss with frequency of 6.2 and 3.7% per locus, respectively (p < 0.01). The predominant type of epimutation appeared to be a postzygotic hypomethylation of the imprinted genes on chromosomes of maternal origin, which was observed in the examined samples in 5.1 and 2.89% of cases, respectively. Replicative study of the methylation status of seven imprinted genes (DLK1, PEG10, PLAGL1, KCNQ1OT1, PEG3, GRB10, and PEG1/MEST) in the enlarged embryo samples supported the results of microarray analysis in respect to both epimutation frequency and predominance of somatic hypomethylation of maternal alleles. It was also demonstrated that pregnancy loss was associated with multilocus methylation defects of imprinted genes, the frequency of which was also significantly increased in the placental tissues of spontaneous abortions in women with recurrent miscarriage.