Recurrent Miscarriages

 

This guideline applies to adults aged 18 and over

Recurrent miscarriage is defined as the loss of 3 consecutive, intrauterine pregnancies or 1 second-trimester miscarriage.
 

• Clinical pregnancies are confirmed either by a positive serum human chorionic gonadotrophin (hCG) or an ultrasound scan.
   
• In cases where a serum HCG or ultrasound scan has not been performed, then a clinical pregnancy is at least 5 to 6 weeks gestation by last menstrual period (LMP).
   
• This definition does not include biochemical pregnancies which are very common and do not usually indicate underlying pathology.

 

Recurrent miscarriage remains unexplained in 50 to 75% of cases. Increasing maternal age is the most important risk factor for recurrent miscarriage.

 

 

 

Consider investigating recurrent pregnancy loss after:              
 

• 3 or more first-trimester miscarriages.
   
• 1 second-trimester miscarriage.

 

History

• Menstrual cycles
   
• Lifestyle factors, especially illicit drugs, smoking, alcohol, and obesity
   
• History of deep vein thrombosis (DVT) or pulmonary embolism (PE) which may suggest antiphospholipid syndrome
   
• Previous successful pregnancies
   
• Previous miscarriages, termination of pregnancies (TOPs), and ectopic pregnancies
   
• All previous investigations, especially abnormal results
   
• Any previous treatments to cervix.

 

Risk factors for recurrent pregnancy loss
 

• Advanced maternal age
   
• Maternal obesity or being significantly underweight
   
• Smoking (either parent)
   
• Alcohol (either parent)
   
• Genetic – translocation, e.g. parental chromosomal rearrangements, embryonic chromosomal abnormalities
   
• Anatomical – congenital uterine abnormalities, e.g. uterine septum, cervical weakness
   
• Endocrine – polycystic ovary syndrome (PCOS), poorly controlled diabetes, thyroid dysfunction, hyperprolactinaemia, e.g. oligomenorrhoea

 

Examination
 

• BMI
   
• Consider performing abdominal examination and speculum examination to check for obvious uterine or cervical abnormalities, e.g. double cervix.
   
• Ensure cervical screening is up to date.

 

 

 

Pelvic USS (non pregnant)

Day 2-5 FSH

 

 

Information to include when referring: 

• Details of full obstetric history (include miscarriages/ TOPs/ ectopic pregnancies)
   
• Whether any previous treatment to cervix (if so please include date of last smear & result)
   
• Relevant past medical / surgical history
   
• Current regular medication

Investigations prior to referral

• Pelvic USS (non pregnant)

 

No formal advice and guidance service available.

 

For professionals:

• Recurrent MiscarriageGreen-top Guideline No. 17 - Regan - 2023 - BJOG: An International Journal of Obstetrics & Gynaecology - Wiley Online Library
• InvestigationAndTreatmentOfCouplesWithRecurrentMiscarriage.pdf (cornwall.nhs.uk)

For patients: 

• Miscarriage Association – Leaflets
• The Ectopic Pregnancy Trust – Leaflets
• Tommy's – Recurrent Miscarriage

 

 

 

 

Review date	04/01/2024
Next review date	04/01/2026
Clinical editor	Dr Melanie Schick, GP
Contributors	Miss Lisa Verity, Consultant Gynaecologist, RCHT