10–15% of all clinically recognised pregnancies end in a miscarriage
the theoretical risk of three consecutive pregnancy losses that expected by chance alone is 0.34%.
This incidence is greater than that expected by chance alone---Recurrent miscarriage affects 1% of all women ---Hence, only a proportion of women presenting with recurrent miscarriage will have a persistent underlying cause for their pregnancy losses
Recurrent miscarriage is a heterogeneous condition that has many possible causes; more than one contributory factor may underlie the recurrent pregnancy losses.
each may have had a different cause.
Genetic factors Anatomical factors Endocrine Infective agents Immune factors Inhereted Thrombophilic defect Explained Un-explained Recurent Miscarriage Enviromental factors Body Cervix Paternal karyotyping Cytogenetic Of miscarriage C I Uterine anomalies APS Bacterial Vaginosis
Investigations and treatments Recent information indicates that women should look into RPL testing after two losses when it used to be common to wait until three. This is especially important for women in their 30s and 40s
EPAUs should use and develop diagnostic and therapeutic algorithms of care.
In particular, these should include management of 'suspected ectopic pregnancy' (including serum hCG) and the 'indeterminate' ultrasound scan.
EPAUs should have access to transvaginal ultrasound with staff appropriately trained in its use.
Non-sensitised rhesus (Rh) negative women should receive anti-D immunoglobulin in the following situations: ectopic pregnancy, all miscarriages over 12 weeks (including threatened), all miscarriages where the uterus is evacuated, and for threatened miscarriages under 12 weeks when bleeding is heavy or associated with pain.
The reported prevalence of uterine anomalies in recurrent miscarriage populations range between 1.8% and 37.6%.
The prevalence of uterine malformations appears to be higher in women with late miscarriages compared with women who suffer early miscarriages but this may be related to the cervical weakness that is frequently associated with uterine malformation.
untreated uterine anomalies has a term delivery rate of only 50%.
Open uterine surgery is associated with postoperative infertility and carries a significant risk of uterine scar rupture during pregnancy. These complications are less likely to occur after hysteroscopic surgery but no randomised trial assessing the benefits of surgical correction of uterine abnormalities on pregnancy outcome has been performed.
If fibroids are detected on the inside of the uterus (termed submucous fibroids) and distort the uterine lining, they are a significant cause of reproductive problems and should be removed. It is less clear whether fibroids in the wall of the uterus cause reproductive problems
The routine use of hysterosalpingography as a screening test for uterine anomalies in women with recurrent miscarriage is questionable .
It is associated with patient discomfort,
carries a risk of pelvic infection and radiation exposure
and is no more sensitive than the non-invasive two dimensional pelvic ultrasound assessment of the uterine cavity with (or without) Sonohysterography when performed by skilled and experienced personnel.
Cervical cerclage is associated with potential hazards related to the surgery and the risk of stimulating uterine contractions and hence should only be considered in women who are likely to benefit.
Cervical weakness is often over-diagnosed as a cause of mid-trimester miscarriage.
The diagnosis is usually based on a history of late miscarriage, preceded by spontaneous rupture of membranes or painless cervical dilatation.
Transvaginal ultrasound assessment of the cervix during pregnancy may be useful in predicting preterm birth in some cases of suspected cervical weakness
Transabdominal cerclage has been advocated as a treatment for second-trimester miscarriage and the prevention of early preterm labour in selected women with previous failed transvaginal cerclage and/or a very short and scarred cervix
Routine screening for occult diabetes and thyroid disease with oral glucose tolerance and thyroid function tests in asymptomatic women presenting with recurrent miscarriage is uninformative
well-controlled diabetes mellitus is not a risk factor for recurrent miscarriage, nor is treated thyroid dysfunction
There is insufficient evidence to evaluate the effect of progesterone supplementation in pregnancy to prevent a miscarriage
hormonal treatments for luteal phase deficiency concluded that the benefits are uncertain the low progesterone levels that have been reported in early pregnancy loss may reflect a pregnancy that has already failed. Exogenous progesterone supplementation should only be used in the context of randomised controlled trials.
Progesterone doesn't prevent miscarriages. Miscarriages happen for many reasons,
but lack of progesterone as a cause for miscarriage is not proven. The low progesterone levels found in pregnancies which go on to become miscarriages is a sign that the pregnancy is already failing
There is insufficient evidence to evaluate the effect of human chorionic gonadotrophin (hCG) in pregnancy to prevent miscarriage .
early pregnancy hCG supplementation failed to show any benefit in pregnancy outcome
Prepregnancy suppression of high luteinising hormone (LH) concentration among ovulatory women with recurrent miscarriage and polycystic ovaries who hypersecrete LH does not improve the live birth rate
the outcome of pregnancy without pituitary suppression is similar to that of patients without raised LH.
Polycystic ovary morphology itself does not predict an increased risk of future pregnancy loss among ovulatory women with a history of recurrent miscarriage who conceive spontaneously .
pelvic ultrasound criteria, is significantly higher among women with recurrent miscarriage (41%) when compared with the general population (22%).
However, despite this high prevalence, polycystic ovary morphology itself does not predict an increased risk of future pregnancy loss among ovulatory women with a history of recurrent miscarriage who conceive spontaneously.
There is insufficient evidence to assess the effect of hyperprolactinaemia as a risk factor for recurrent miscarriage .
Immune factors One in ten women with recurrent miscarriages show evidence of auto immune factors on investigation As much as 40 percent of unexplained infertility may be the result of immune problems, as are as many as 80 percent of "unexplained" pregnancy losses. Unfortunately for couples with immunological problems, their chances of recurrent loss increase with each successive pregnancy.
To diagnose APS it is mandatory that the patient should have two positive tests at least six weeks apart for either lupus anticoagulant or anticardiolipin (aCL) antibodies of IgG and/or IgM class present in medium or high titre.
Adverse pregnancy outcomes include
(a) three or more consecutive miscarriages before ten weeks of gestation,
(b) one or more morphologically normal fetal deaths after the tenth week of gestation and
(c) one or more preterm births before the 34th week of gestation due to severe pre-eclampsia, eclampsia or placental insufficiency.
Currently there is no reliable evidence to show that steroids improve the live birth rate of women with recurrent miscarriage associated with aPL when compared with other treatment modalities; their use may provoke significant maternal and fetal morbidity.
In women with a history of recurrent miscarriage and aPL, future live birth rate is significantly improved when a combination therapy of aspirin plus heparin is prescribed.
Pregnancies associated with aPL treated with aspirin and heparin remain at high risk of complications during all three trimesters .
Immunotherapy, including paternal cell immunisation, third-party donor leucocytes, trophoblast membranes and intravenous immunoglobulin (IVIG), in women with previous unexplained recurrent miscarriage does not improve the live birth rate
TORCH (toxoplasmosis rubella, cytomegalovirus and herpes simplex virus), other [congenital syphilis and viruses], screening is unhelpful in the investigation of recurrent miscarriage.
For an infective agent to be implicated in the aetiology of repeated pregnancy loss, it must be capable of persisting in the genital tract and avoiding detection or must cause insufficient symptoms to disturb the women. Toxoplasmosis, rubella, cytomegalovirus, herpes and listeria infections do not fulfil these criteria and routine TORCH screening should be abandone
Screening for and treatment of bacterial vaginosis in early pregnancy among high risk women with a previous history of second-trimester miscarriage or spontaneous preterm labour may reduce the risk of recurrent late loss and preterm birth.
Pre and Post-conceptional, broad-spectrum intravenous antibiotic therapy was used in patients with multiple miscarriages
Although this is a relatively small series and does not establish a cause and effect relationship between Group B Streptococcus and habitual abortions, the beneficial effects of antibiotic therapy is unquestionable
Exposture to noxious or toxic substances are known to be associated with recurrent miscarriage ( social drugs, cigarretes,alcohol and caffeine ,anaestetic gases,petrolium products )
Unexplained recurrent miscarriage In about half the women in the research studies, no cause could be found, so no specific treatment could be given . However, this group responded very well to a programme which removed as many stress factors as possible from their lives, resulting in an 80% success rate with the subsequent pregnancy
Women with unexplained recurrent miscarriage have an excellent prognosis for future pregnancy outcome without pharmacological intervention if offered supportive care alone in the setting of a dedicated early pregnancy assessment unit . After all these investigations 50% of recurrent aborters will be found to have no abnormalities and these should be attributed to chromosomal defect in the conceptus.
According to the American College of Obstetricians and Gynecologists
cultures for bacteria and viruses
glucose tolerance testing
antibodies to infectious agents
paternal human leukocyte antigen status, or maternal antiparental antibodies
are not beneficial and, therefore,
are not recommended in the evaluation of otherwise normal women with recurrent pregnancy loss .
Things unlikely to cause recurrent miscarriage
Retroversion - or backward tilting of the uterus.
Infection - such as toxoplasmosis, listeria, brucella, chlamydia, herpes simplex and cytomegalovirus.
Endocrine or metabolic disease - hypothyroidism (underactive thyroid), diabetes mellitus, Crohn's disease, sickle cell or endometriosis.
Occupational exposures - very little reliable evidence exists for things such as herbicide spraying, electromagnetic fields, chemical inhalation, anaesthetic gases or VDU usage.
Not resting enough - bedrest doesn't alter whether you miscarry or not. Nor does working when you're pregnant, exercise, making love or flying.
The value of psychological support in improving pregnancy outcome has not been tested in the form of a randomised controlled trial. However, data from several non-randomised studies86–88 have suggested that attendance at a dedicated early pregnancy clinic has a beneficial effect, although the mechanism is unclear
All professionals should be aware of the psychological sequelae associated with miscarriage and should provide support and follow-up, as well as access to formal counselling when necessary.