Poor Obstetric History

Previous unexplained stillbirth in the third trimester

Previous second trimester miscarriage

Indication for cervical cerclage

Two or more previous unexplained fetal deaths

When to test for antiphospholipid syndrome

Previous preterm delivery

Thorough history taking is essential. A special clinic should provide expert management of women with recurrent problems in previous pregnancies. 

PREVIOUS UNEXPLAINED STILLBIRTH IN THE THIRD TRIMESTER

• Advise against smoking/alcohol/illicit drugs
• Refer to the dietician for a healthy eating plan if BMI>30 at booking
• Do a dating ultrasound scan at the first contact with the patient, then book a 1^st trimester scan (11-14w) or if further along an anomaly scan at 18-23 weeks
• Pull booking bloods and TSH
• Take blood for APS:
  • Anticardiolipin antibodies - ACLA
  • Anti-Beta 2 glycoprotein 1 antibody – anti-B2GP1
  • Lupus anticoagulant – LA (take sample from an uncuffed arm)
  • Antinuclear antibodies - ANA
• Consider thrombotic screen, including Factor V Leiden, Protein C & Protein S  for APS-negative patients (specialist clinic only) – best done outside of pregnancy
• Ask the woman to count fetal movements from 28 weeks (10 in 2 hours)
• Screen for gestational diabetes from 24 weeks with a 75g OGTT
• Book an ultrasound and umbilical artery Doppler at 26 weeks & 32 weeks
• Review the woman weekly from 36 weeks
• Deliver at 38-39 weeks

Antiphospholipid Syndrome (APS)

The diagnosis of APS requires at least 1 of the clinical criteria & 1 of the laboratory criteria. Laboratory criteria must be positive on 2 or more occasions, at least 12 weeks apart. Due to the fact that the window of opportunity to help prevent further damage to the placenta is small, the patient is started on treatment based on one set of bloods. Thus she should be retested 12 weeks after delivery & if still positive, be referred to medicine.

Clinical criteria

• 1 or more unexplained deaths of morphologically normal fetuses at or beyond the 10th week of gestation, with normal fetal morphology documented by ultrasound or by direct examination of the fetus
• 1 or more premature births of morphologically normal neonates before the 34th week of gestation because of eclampsia or severe pre-eclampsia
• 3 or more unexplained consecutive spontaneous miscarriges before the 10th week of gestation

Laboratory criteria – at least one must be positive

• Lupus anticoagulant (LA)
• Anticardiolipin antibody (ACLA)
• Anti-Beta 2 glycoprotein 1 antibody (anti-B2GP1)

APS is treated with enoxaparin 0.5 mg/kg SC and aspirin 75-100 mg orally, daily - given from 6 weeks gestation up to term.

PREVIOUS SECOND TRIMESTER MISCARRIAGE

• Take a careful history of the miscarriage/s:
  • In addition to the above points on history
    • Evidence of cervical weakness – rapid painless delivery of a live fetus after membrane rupture or delivered with intact membranes. Note that a very premature fetus may die during the delivery process so documentation of fetal heart activity is important prior to delivery.
    • Was a baby seen, and was it alive at delivery?
• On vaginal examination, feel for dilatation & length of the cervix
• Do a dating ultrasound scan at the first antenatal visit. Arrange a 1^st trimester scan including cervical length. If already past 14 weeks, arrange a cervical length scan as soon as possible. This may be repeated after 2 to 4 weeks to look for shortening, or at the 18-23 weeks scan.
• Decide on the need for cervical cerclage, & type of cerclage.

INDICATIONS FOR CERVICAL CERCLAGE 

• A history strongly suggestive of cervical weakness
• Prior cervical cerclage for cervical weakness
• Three consecutive second trimester miscarriages (unless fetuses born dead)
• Short cervix on transvaginal ultrasound scan (<2.5 cm), or open cervix felt, in a woman with a history of 2^nd trimester loss or previous preterm labour (<34w)
• Significant cervical shortening over 4 weeks on serial ultrasound scans
• Uterine anomalies (senior to decide)

Cervical cerclage is usually performed at 14 weeks, but may be done up to 24 weeks. ‘Rescue’ cerclage may be done in selected cases at 25-26 weeks

TWO OR MORE PREVIOUS UNEXPLAINED FETAL DEATHS 

• The main concern is antiphospholipid syndrome (APS) or thrombophilia
• Using a plain (red-topped) tube, take blood for APS:
  • Antinuclear antibodies
  • Anticardiolipin antibodies – IgG, IgM, IgA
  • Anti-Beta 2 glycoprotein1 antibody
• Consider thrombotic screen, including Factor V Leiden, Protein C and Protein S  for APS-negative patients (specialist clinic only)

WHEN TO TEST FOR ANTIPHOSPHOLIPID SYNDROME

• Two or more unexplained fetal deaths
• Previous fetal death associated with early onset pre-eclampsia
• Recurrent fetal growth restriction with or without hypertension
• One unexplained fetal death & a history of thromboembolism

PREVIOUS PRETERM DELIVERY

This refers to the delivery of a preterm baby that died or required special care, in the previous pregnancy

• Obtain a good history of the preterm birth
• Do an ultrasound scan at the first antenatal visit, including estimation of cervical length on transvaginal scan
• Before 24 weeks, feel for dilatation of the cervix on vaginal examination
• Look for evidence of bacterial vaginosis or trichomoniasis and treat appropriately (metronidazole 2 g orally as a single dose)
• Consider giving progesterone vaginal pessaries 200 mg daily for women with recurrent preterm delivery (consultant/special clinic decision)
• Consider cervical cerclage based on cervical length findings (consultant/special clinic decision)
• Consider prophylactic corticosteroids (betamethasone 12 mg IMI & repeated after 12 hours) at ≥26 weeks
• From 34 weeks, no further specific management is needed & the woman can continue antenatal care and plan for delivery at her local clinic