Late termination of pregnancy, although not rigidly defined, is typically considered as abortion after 20 weeks gestation, and accounts for less than five per cent of all abortions in Australia. It is notable for increased procedural complications compared with first trimester procedures and evokes high levels of conflicting emotions in the community. In Australia, data about late terminations are limited and biased by the distribution of services and legislative variation between the states. This legislative variance leads to limitations around reporting and data availability, with no standardised data collection system, as well as limited provision and access to abortion services. This is especially so for women seeking late termination, with its required expertise and specific ethical and legal considerations.
Indications for late termination
The majority of terminations after 20 weeks gestation in Australia are performed for severe fetal abnormalities or maternal illness, where continuing the pregnancy to viability would potentially compromise the life of the woman. Access to abortion beyond 20 weeks gestation in Australia for other reasons, such as maternal psychological distress or socioeconomic disadvantage, is more restrictive and in some states non-existent. However, the provision of safe late termination services is an imperative of a health system that recommends fetal anomaly screening as a core component of obstetric care. While aneuploidy screening has largely moved to the first trimester, the majority of fetal structural abnormalities remain undiagnosed until the 19 to 20-week fetal anatomy survey in general screening environments. To ensure all appropriate investigations and counselling are completed, parental decision-making is often not possible until well into the second trimester of pregnancy. The RANZCOG guideline on late termination ‘recognises special circumstances where late termination of pregnancy may be regarded by the managing clinicians and the patient as the most suitable option in the particular circumstance’, referring specifically to twins discordant for anomalies, and conditions where the diagnosis or prognosis is not known until later gestation.1
Methods of termination
There are two basic methods for conducting a late termination of pregnancy: a surgical approach (usually dilatation and evacuation with pre-procedural cervical preparation) and a medical approach (induction of labour with prostaglandin preparations, typically with pre-procedural mifepristone). There has been a progressive shift in many countries (the US being a significant exception) from a surgical to a medical approach for pregnancy termination. Both techniques have reasonable safety profiles provided the medical practitioner is adequately trained and skilled in the specific technique employed.
Dilatation and evacuation (D&E) is the predominant surgical technique used for late abortion, although in rare circumstances, hysterotomy or even hysterectomy may be used. With the increasing prevalence of placenta accreta spectrum, hysterectomy may be required when this condition complicates a pregnancy with a severe fetal malformation. Prior to the conduct of a D&E, the cervix requires pre-procedural preparation to reduce the risk of cervical laceration and uterine perforation. Agents used for cervical preparation include pharmacologic agents (such as mifepristone or misoprostol) or osmotic dilators (for example, Laminaria tents [a hydroscopic kelp product] or the synthetic hydrophilic polymer rod, Dilapan). Laminaria typically requires 12–24 hours to achieve maximal cervical dilation compared with 4–6 hours for Dilapan, and the latter is preferred for same-day preparation procedures.2 Pharmacologic agents, although effective in earlier gestations, do not typically provide enough cervical dilation for later gestation D&E procedures when used alone, compared with osmotic dilators. With advancing gestation, more cervical preparation is required. Many practitioners combine osmotic dilators and mifepristone and/or misoprostol, resulting in greater pre-procedural cervical dilation and shorter procedure times.3
Technically, D&E is usually performed under ultrasound guidance with grasping forceps to remove the fetus and placenta, or intact delivery if sufficient cervical dilation can be achieved. There are no robust data to compare the two techniques, although intact D&E requires more time to achieve adequate cervical dilation (usually 1–2 days).
Medical abortion has been significantly affected by the introduction of the anti-progesterone mifepristone, which, when used prior to the administration of prostaglandins (usually the PGE1 analogue misoprostol), reduces the induction to abortion interval by 40–50 per cent compared with the use of prostaglandins alone.4 Although able to be used at all gestations, the recommended regimens vary with gestation. For late termination (later than 20 weeks gestation), the recommended regimen is 200mg mifepristone orally followed 24–48 hours later by 400µg misoprostol (vaginally or sublingually) every 3–4 hours until fetal expulsion.5 For late medical termination, a loading misoprostol dose is usually omitted, although this is typically a component of earlier gestation medical termination protocols. Variations in misoprostol dosage regimens are common in late termination, typically based on parity, gestation and prior uterine surgery. Practitioners are encouraged to consider the individual clinical circumstances when prescribing this prostaglandin. Median duration from commencement to expulsion increases as gestation advances, presumably secondary to the greater cervical dilation required to expel the fetus. Virtually all women will have delivered within 24 hours of prostaglandin commencement, with a median duration of 10–12 hours. As with surgical techniques, procedural complications tend to increase with gestation for medical abortion, with the exception of placental retention rates, which decline with advancing gestation.6 The use of prophylactic third-stage oxytocics to reduce placental retention is recommended.
One infrequently discussed aspect of late abortion is feticide, where specific interventions occur to ensure the death of the fetus prior to expulsion. Unintended live birth after abortion can be emotionally difficult for many (although not all) women and poses difficulties for health professionals, both in terms of process and emotion. In a randomised controlled trial of feticide prior to D&E, 91 per cent of participants expressed their preference for fetal death prior to termination.7 Since 1996, the Royal College of Obstetricians and Gynaecologists has recommended consideration of feticide after 21+6 weeks ‘to ensure there is no risk of a live birth’.8
In general, feticide is performed by ultrasound specialists who have skills in accessing the fetal circulation to instill intracardiac potassium chloride (KCl) or intrafunic lignocaine, resulting in cessation of fetal cardiac activity prior to the commencement of the termination procedure. In some situations, intra-amniotic or intrafetal digoxin is administered, although this is rarely performed under the auspices of an obstetric ultrasound specialist and has a recognised failure rate. Intracardiac KCl is an effective and safe method to induce prompt fetal cardiac asystole with minimal maternal risk.9 Little consideration has been provided to the psychological impact on the healthcare team in the provision of a feticide service, even though it is a general recommendation for terminations of pregnancy at gestations later than 22–23 weeks.
In summary, feticide and late termination are necessary, but difficult, parts of our profession. They are mostly undertaken in challenging circumstances, with parents confronted by unexpected fetal diagnoses, or those most vulnerable to both the late diagnosis and burdens of pregnancy. This difficulty is compounded by the current legislative variance between Australian states at both practitioner and system levels. For those performing late termination, a clear legal framework is essential and for systems providing antenatal care, a clear pathway to accessing safe, integrated termination services is crucial.10
Unfortunately, the burden of this variance is disproportionately shouldered by the most vulnerable in our communities, who may lack the financial and social supports required to access what, in a worst case scenario, may entail a complicated hospital admission in a different state. Fair and equitable access to safe late termination of pregnancy is a reasonable expectation of patients offered routine anomaly screening.