Miscarriage and Recurrent Loss: Facts and Support

Understanding loss

Miscarriage is common, occurring in roughly 1 in 5 known pregnancies, most often due to random chromosomal differences—not something the parent did. Recurrent loss (two or more) warrants evaluation for treatable causes.

Investigations may include hormonal, anatomical, genetic, and clotting assessments. Many people go on to have healthy pregnancies after evaluation and support.

Understanding pregnancy loss

Miscarriage is common, most often occurring in the first trimester, and is usually caused by chromosomal factors in the developing pregnancy rather than anything the parent did. It is important to know that ordinary activity, stress, or sex does not cause miscarriage. Recurrent loss—typically defined as two or three or more—warrants investigation.

Support and next steps

After recurrent loss, tests may look for hormonal, structural, clotting, or genetic factors, and many identified causes can be treated, improving future chances. Emotionally, grief after loss is real and valid, and support—from partners, counselors, or peer groups—matters. Most people who experience a miscarriage go on to have healthy pregnancies.

How Common Is Miscarriage and Why It Happens

Miscarriage — the spontaneous loss of a pregnancy before 24 weeks of gestation — is far more common than many people realise. Approximately 10–20% of clinically recognised pregnancies (those confirmed by a positive test) end in miscarriage, and the true rate including very early losses that resolve before a missed period is estimated to be even higher. The vast majority of miscarriages — around 50–70% — are caused by chromosomal abnormalities in the embryo, specifically random errors in chromosome number that occur during the formation of the egg, the sperm, or the early cell divisions after fertilisation.

These chromosomal errors are not inherited from either parent in most cases; they are spontaneous events ('de novo') that increase in frequency with advancing age, particularly maternal age. An aneuploid embryo — one with an incorrect number of chromosomes — typically fails to develop past the early embryonic period, and the pregnancy ends as a miscarriage. From an evolutionary perspective, miscarriage can be understood as the body's mechanism for ending pregnancies that cannot result in a viable child, though this biological framing offers little comfort to those experiencing loss.

Types of Miscarriage: Clinical Definitions

Miscarriage is not a single event but a clinical spectrum. A threatened miscarriage involves vaginal bleeding in early pregnancy with a closed cervix and a viable embryo on ultrasound — some of these pregnancies continue normally. An inevitable miscarriage involves bleeding and cervical dilation; the pregnancy cannot continue. An incomplete miscarriage occurs when some pregnancy tissue remains in the uterus after the main loss. A complete miscarriage means all pregnancy tissue has passed naturally. A missed (or silent) miscarriage — also called a delayed miscarriage — occurs when the embryo has died but no bleeding or cramping has yet occurred; it is typically discovered incidentally on an early pregnancy scan.

Biochemical pregnancy loss — a very early loss that occurs after a positive urine or blood pregnancy test but before a heartbeat is detectable on ultrasound — is also a recognised form of pregnancy loss. These losses can be emotionally significant even if they resolve quickly. Recurrent miscarriage, defined as three or more consecutive losses by classic definitions (some clinicians now use two or more), affects approximately 1–2% of couples and warrants investigation for underlying causes.

Investigation of Recurrent Miscarriage

When recurrent pregnancy loss is diagnosed, a structured investigation programme looks for conditions that may be treatable and may improve future pregnancy outcomes. The principal investigations include: antiphospholipid antibody testing (anticardiolipin antibodies, beta-2 glycoprotein I antibodies, and lupus anticoagulant) to identify antiphospholipid syndrome (APS); parental chromosome karyotyping to identify balanced translocations or other structural rearrangements that affect embryo viability; uterine assessment with a hysteroscopy, saline infusion sonography, or 3D ultrasound to identify uterine septum, submucous fibroids, or intrauterine adhesions; and thyroid function testing including thyroid antibodies.

It is important to have realistic expectations about this investigation: in approximately 50% of couples with recurrent miscarriage, no identifiable cause is found even after thorough assessment. This is called unexplained recurrent pregnancy loss. This does not mean the losses are random bad luck with no possibility of improvement — the prognosis for subsequent live birth in unexplained recurrent miscarriage is still approximately 60–70% with supportive care alone — but it does mean there is no specific targeted treatment available beyond optimising general health and offering emotional support.

Antiphospholipid Syndrome and Treatment

Antiphospholipid syndrome is the most important treatable cause of recurrent miscarriage, identified in approximately 15–20% of women with recurrent loss. APS is an acquired autoimmune thrombophilia in which antibodies attack phospholipid-binding proteins, promoting blood clot formation in placental vessels and impairing placental development. In addition to miscarriage, APS is associated with late pregnancy losses, placental insufficiency, and maternal thrombosis.

The standard treatment for APS in pregnancy is a combination of low-dose aspirin (75 mg daily, started before conception) and low-molecular-weight heparin (LMWH) injections, which together reduce placental clotting and improve placental blood flow. This combination reduces miscarriage risk in APS from around 90% to below 30% — a dramatic improvement. Treatment is continued until 34–37 weeks of gestation in most protocols. Regular monitoring throughout pregnancy is essential, as APS is also associated with preeclampsia and fetal growth restriction.

Uterine Factors and Correction

Structural uterine abnormalities — particularly a uterine septum, which divides the uterine cavity with a fibrous or muscular partition — are associated with miscarriage because implantation on the poorly vascularised septal tissue results in inadequate early placentation. Hysteroscopic resection of a uterine septum is a day-case surgical procedure with a short recovery time. While high-quality randomised trial evidence is limited, observational data consistently show improved pregnancy outcomes after septum resection in women with recurrent loss.

Submucous fibroids — fibroids that project into the uterine cavity — may also impair implantation and early placentation. Their relationship to miscarriage risk depends on their size and the degree to which they distort the cavity. Hysteroscopic removal is recommended for submucous fibroids that significantly alter cavity shape, though again the evidence base for improved outcomes is based primarily on cohort studies. Intrauterine adhesions (Asherman's syndrome) — usually a complication of prior uterine surgery or infection — can cause miscarriage and infertility; hysteroscopic adhesiolysis is the treatment.

Emotional Impact and Support

Miscarriage is a bereavement. The grief that follows pregnancy loss — even very early loss — is real, profound, and often underacknowledged by those around the couple. Society's tendency to treat early miscarriage as 'not really a baby yet' or 'nature's way' can leave those experiencing loss feeling that their grief is disproportionate or illegitimate. In reality, the emotional response to miscarriage often matches the depth of investment and attachment that had already developed, regardless of gestational age.

Common emotional responses include shock, deep sadness, anger, guilt (particularly wondering whether something the person did caused the loss — in the vast majority of cases it did not), anxiety about future pregnancies, and relationship strain. Partners experience grief too, though often in different ways and on different timescales, which can create disconnection. Open communication between partners, validation of each person's experience, and professional counselling when grief is prolonged or impairing functioning are all important support strategies.

Miscarriage Association, Tommy's, and SANDS (for later losses) are UK-based charities offering helplines, online communities, peer support, and evidence-based resources. Internationally, similar organisations exist. For recurrent loss specifically, connecting with others who share this experience can reduce the profound isolation that often accompanies it. Asking your fertility clinic or GP to refer you to a dedicated recurrent miscarriage clinic or counselling service is appropriate and encouraged.

Planning the Next Pregnancy After Loss

After a miscarriage, there is no medical requirement to wait a specific number of cycles before trying again, unless surgery was required (such as surgical management of incomplete miscarriage), in which case clinicians typically advise one recovery cycle. Physically, the body usually recovers quickly. Emotionally, readiness varies enormously — some couples feel ready to try again quickly, others need months to grieve before another attempt feels sustainable. Both responses are valid.

In subsequent pregnancies after recurrent loss, early reassurance scans at 6–8 weeks are offered in most recurrent miscarriage clinics to detect a fetal heartbeat — a landmark that dramatically improves the odds of an ongoing pregnancy. Many couples experience significant anxiety throughout subsequent pregnancies after loss, and acknowledging this anxiety as a reasonable response — rather than treating it as excessive — is part of compassionate care. Progesterone supplementation (vaginal pessaries) is offered by some recurrent miscarriage clinics for women with unexplained recurrent loss — particularly those with a short luteal phase — though the evidence for routine use is mixed and clinic policies vary.

Frequently Asked Questions

Q: Did I cause my miscarriage by exercising, having sex, or not resting enough? A: Almost certainly not. The causes of miscarriage are overwhelmingly embryonic (chromosomal abnormalities) or medical (APS, uterine factors). Moderate exercise, sexual intercourse, lifting, travel, and stress do not cause miscarriage in otherwise healthy pregnancies. This is one of the most important misconceptions to correct, because many people carry entirely unwarranted guilt for years after a loss.

Q: Should I test the pregnancy tissue after a miscarriage? A: Chromosomal analysis of pregnancy tissue (products of conception) after a miscarriage can identify whether the loss was due to chromosomal abnormality, which is reassuring information. It is particularly useful after recurrent losses. However, tissue must be sent fresh, the test does not always succeed, and cell culture contamination can give misleading results (XX result may reflect maternal cells). Chromosomal microarray analysis is more accurate than conventional karyotyping in this context. Discuss with your clinician whether testing is feasible and appropriate after your specific loss.

Q: We have been told our losses are 'unexplained'. Is there anything we can do? A: Several supportive measures have shown some benefit in unexplained recurrent miscarriage. These include optimising general health (stopping smoking, achieving healthy weight, managing thyroid disease), low-dose aspirin in some centres (though evidence for aspirin without APS is limited), progesterone supplementation through the first trimester (evidence is strengthening, particularly for women with previous miscarriage), stress reduction, and close monitoring in early pregnancy. Psychological support alone has been shown to improve live birth rates — likely through reducing anxiety-driven physiological stress responses. The live birth rate with supportive care in unexplained recurrent miscarriage is genuinely encouraging at 60–70%.

Q: After three miscarriages and no cause found, would IVF with PGT-A help? A: PGT-A — pre-implantation genetic testing for aneuploidy — selects chromosomally normal embryos for transfer and reduces the miscarriage rate per transfer. However, it does not necessarily improve the cumulative live birth rate because embryos that would have been lost are identified before transfer rather than after, and the total number of viable embryos is not increased. For women who find repeated pregnancy losses emotionally devastating, PGT-A may offer a meaningful reduction in loss events per transfer. For others, the invasiveness and cost of IVF may not be justified if the background live birth rate with expectant management is reasonable. This decision deserves detailed discussion with a specialist in recurrent miscarriage.