Introduction

Women of child-bearing potential (typically defined as aged 13–50) regularly undergo anaesthesia for surgery in both elective and emergency settings. Prior to undergoing anaesthesia, the pregnancy status for these patients should be established. As part of preoperative screening, in the UK most of these patients will be asked regarding their pregnancy status, as per National Institute for Health and Care Excellence (NICE) guidelines, and if unsure be offered a test. The pregnancy status of patients is of importance as there are additional risks associated with this as a result of the surgery or anaesthesia itself. Until it is born, the fetus itself does not have a legal personality or rights, and decisions are not made based on the welfare of the baby, but for the woman carrying the child.

Risks of surgery and anaesthesia in pregnancy

The associated risks include those relating to the fetus and those specific to the mother. With regards to the fetus, within the first trimester there is the potential for miscarriage, as well as teratogenic effects of drugs resulting in congenital abnormalities such as neural tube defects and hydrocephalus. Within the second and third trimesters there are risks of preterm delivery, low birthweight, and stillbirth. Pregnant patients have a risk of venous thromboembolism that is higher than non-pregnant patients, and this is further increased by having surgery. There are also increased risks associated with surgery whilst pregnant including aspiration, prolonged hospital stays, and of maternal death. Some studies have suggested an increase in rates of miscarriage in patients undergoing anaesthesia, but this is difficult to compare to the background rates of miscarriage in pregnant patients that do not undergo surgery. Most studies relate to animal testing whose results may not translate well to real clinical scenarios in humans. There is no clear association between anaesthesia and surgery and adverse pregnancy outcomes. The American College of Obstetricians and Gynaecologists (ACOG) advise that common anaesthetic drugs currently used in practice are not known to negatively affect the growth and development of the baby and are safe to use in pregnancy. There are however confounding factors which may contribute to the risk making it difficult to quantify, such as administration of multiple drugs both anaesthetic and otherwise including antibiotics, stress, general illness, fever, and altered physiology of pregnancy. In addition, the effect of radiation exposure from X-rays or computed tomography (CT) imaging related to the procedure should be considered.

Risks vary depending on the stage of the pregnancy. The fetus is most vulnerable in the earlier stages of pregnancy. This is the time when the woman has the highest likelihood of being unaware of the pregnancy, and so testing at this stage is of the most importance. Later in gestation, the mother is more likely to already be aware of the pregnancy – and an unknown pregnancy at this stage is likely to be complicated by other factors, either health or social related, and not covered here.

Preoperative pregnancy testing

About 1–2% of pregnant women undergo non-obstetric surgery during their pregnancy. The most common indications for abdominal surgery performed during pregnancy are for appendicectomy or cholecystectomy, or for ovarian pathologies. ^, Other common reasons for surgery are in relation to trauma.

Preoperative testing of pregnancy from either urine or blood samples allows for a discussion between the patient and medical team about risks involved and for appropriate planning to take place. The overall decision of whether to proceed with surgery may not change. The surgical approach and anaesthetic technique can be adapted to minimize the risk to the pregnancy. The ACOG recommends entirely elective procedures be postponed to outwith pregnancy and after a suitable time period post-partum, whilst urgent procedures that cannot be delayed are best performed in the second trimester, an example of this being for cancer-related surgeries. Emergency surgery could take place at any time as a balance of risks. The surgical approach could be adapted once pregnancy status is known. For example, there are higher rates of miscarriage for laparoscopic compared to open appendicectomy, compared to lower rates of miscarriage for laparoscopic cholecystectomy compared to the alterative open procedure.

Consent

In the UK as per NICE guidelines, pregnancy testing is offered to women prior to surgery, both elective and emergency. In order for the test to be done, the patient should be able to consent. For consent to be valid it requires that the decision be made voluntarily, the patient must be fully informed and must have the capacity to be able to make the decision. Importantly, the patient should not feel like their refusal or willingness to consent to the test should affect any treatment decisions, or be influenced by anyone else for example family members present at the time of asking. For example, a child may not want to consent as they see it as admitting sexual activity. The healthcare professionals discussing pregnancy testing with the patient should be aware of the risks themselves in order to allow the patient to make an informed choice. A lack of medical knowledge with respect to doctors has been shown to affect the ability for patients to provide informed consent in the context of early pregnancy Down’s syndrome screening.

Patient refusal to consent

Every patient has the right to refuse consent which must be respected if they have capacity, even if this could result in their death or the death of an unborn child. In the case of a patient refusing to consent to pregnancy testing a discussion regarding the individual risks and benefits of proceeding with surgery with a potential unknown pregnancy should take place. In order to proceed the patient should be able to demonstrate awareness of the additional risks associated with undergoing surgery whilst pregnant in the event that they are actually pregnant. This may mean that purely elective procedures do not go ahead without patient consent to testing.

Capacity

All adult patients are presumed to have the capacity to consent and make decisions regarding their medical treatment so long as they are able to demonstrate the following: their ability to understand the information being given to them, retain that information, be able to use the information provided to make a decision, and be able to communicate that decision to others. An adult may lack capacity due to a number of reasons which may be short or long term in nature. Examples include mental health conditions (acute or chronic), dementia, learning disabilities, as well as acute illness or intoxication causing confusion, drowsiness or loss of consciousness. Capacity should be assessed at the time it is required as it can change over time. The Mental Capacity Act (MCA) or Adults with Incapacity (Scotland) Act should be used when treating adults who lack capacity, with decisions made in their best interests. Some patients may have guardianship orders or lasting power of attorney (LPA) in which case the relevant persons should be consulted when making decisions for the patient. With regards to pregnancy testing for surgery, the appropriate person should be sought if the patient is unable to consent, which could be done at the time of consenting for surgery.

In the event of an unconscious patient requiring emergency surgery, if the patient is not previously known to be pregnant, pregnancy testing should be performed in order to have all of the relevant information available. However, given the emergency nature of the surgery, the additional risks are likely to be outweighed by the benefits of the surgery, and would likely proceed regardless of a positive pregnancy test. As the fetus has no legal personality until it has been born the result is useful to guide decisions but ultimately for a patient who lacks capacity, all decisions should be made in the best interests of the mother. The welfare of the unborn child may however be a priority for the woman, and therefore this should be considered as part of her best interests. Care must be taken to avoid breaching the patient confidentiality, only allowing those directly involved in their care to know about pregnancy status. Advice may need to be sought from the obstetric team (which should be done sensitively). Where the incapacity is short-term, family members should not normally be made aware of the pregnancy before the patient regains capacity.

Capacity in children

In the UK, adolescents over the age of 16 are presumed to have capacity to consent to treatment decisions. The principle of Gillick competency relates to children under 16 years of age. Children must be able to demonstrate that they can understand the treatment required and the implications of their decision, including the associated risks and alternatives, in order to be able to consent to a procedure. However, this does not necessarily apply to refusal of treatment which may lead to their death or permanent harm.

In England a parent or person with parental responsibility, who has legal rights and responsibilities to make decisions for that child, can consent for a 16-or 17-year-old if they lack capacity. However, the young person must provide consent themselves if they are legally capable of doing so, and refusal to consent at this age cannot be overruled by the parent. Once they are aged 18, a parent cannot consent for them even if they lack capacity, unless there is an Order from the Court of Protection. Under the age of 16, a child that has been judged to have capacity can consent to a treatment, and this agreement cannot be overruled by someone with parental responsibility. Conversely, if a competent child under the age of 16 refuses to consent, then this can be overruled by a parent, if the medical team also agree it is in the patient’s best interests.

In Scotland, at age 16 the parents no longer have the right to consent, and a young person without capacity would be treated under a Section 47 certificate under the Adults with Incapacity Act. A child under 16 years of age with capacity who refuses to provide consent is legally entitled to do so and this cannot be overruled by a person with parental responsibility.

Pregnancy testing in teenage girls

With regards to determining pregnancy status in adolescents pre-operatively, studies have shown non-standardized approaches to asking about pregnancy status in teenage girls being used, with the behaviour and appearance of the patient influencing the decision to enquire. Patients may be reluctant to admit to the possibility of a pregnancy especially if questioned in front of others. The incidence of teenage pregnancy in 2013 was 4.9 per 1000. Standard testing has been suggested for all those who have passed menarche. While this standardizes management, it may be seen as an invasion of patient autonomy. False positives can also cause unnecessary additional stresses and mandatory testing may not preserve confidentiality if the information is expected to be shared with parents or carers (which may harm their relationship with the patient). Conversely if routine testing is not performed then the few patients that are pregnant may be unknowingly exposed to additional risks.

Implications of a positive result

In addition to helping with decision-making regarding surgical or anesthetic technique, or relating to timing of surgery, a positive pregnancy test may open up other considerations. When providing the option of performing the test there should be options available to offer support to the patient in the case that an unexpected result comes back. If an unknown pregnancy is discovered, there should an available pathway to refer into antenatal care or suitable access to appropriate services to be able to provide an opportunity to discuss alternatives if the patient does not wish to continue the pregnancy. There is also the possibility of false positive or negative results to consider, which could result in undue stress for the patient.

For any child aged 14–16 who has a positive pregnancy test the local child protection team should be informed, ideally with the patient’s consent. In addition, any child under the age of 13 who admits to sexual activity should also be referred to the child protection team as the law deems them not competent to consent at this age.

Any positive pregnancy test result is confidential information belonging to the patient and permission must be sought from them to share it with a next of kin or partner if the patient has capacity.

Other ethical considerations

The expense of consistently testing all women having an operation as a matter of course in order to identify a small number of previously unknown pregnancies should be weighed against any potential costs of managing any pregnancy-related complications due to coincidental surgery in a patient not previously known to be pregnant. Also of note, preoperative screening selects a pre-determined age group, allowing for some potential pregnancies to lie outwith this age range and therefore potentially being missed, albeit these will be small numbers.

Conclusion

In summary, pregnancy tests are performed to determine the pregnancy status of the patient, to highlight and minimize risks to both the mother and her unborn baby. The patient has to consent to the test, unless they lack capacity as outlined above. An unborn baby has no rights until it is born, therefore whilst the result is useful information, any decisions made should be in the best interests of the woman alone. There are complexities in this process where the patient is under 16 regarding safeguarding, and for patients that lack capacity. This can be a sensitive area for patients and should be approached with consideration of that, and confidentiality should be maintained throughout.