oPatientPlus articles are written by UK doctors and are based on research evidence, UK and European Guidelines. They are designed for health professionals to use, so you may find the language more technical than the condition leaflets.
See also separate articles Antenatal Care, Antenatal Screening for Down's Syndrome, Prenatal Diagnosis. This article cannot cover all areas of clinical practice associated with the proper care of pregnant women, but gives an overview of important areas, based on the latest guidance. For the full advice offered by the National Institute for Health and Clinical Excellence (NICE) on routine care of healthy pregnant women, see 'Document references' the end of the article.
Diagnosis of pregnancy and calculation of gestational age
- Diagnosis of pregnancy is best confirmed using a urine-testing kit that determines the presence of beta human chorionic gonadotrophin (beta-hCG).
- Many women will have confirmed their own pregnancy by such means.
- Where the absence of menses is the only current indicator of early pregnancy, it is important to confirm pregnancy using a testing kit.
- An early ultrasound scan should be offered at 10-13 weeks, to determine gestational age and detect multiple pregnancies. This has added benefits of ensuring consistency of gestational age assessments and improving the performance of mid-trimester serum screening for Down's syndrome, and reducing the need for induction of labour at >41 weeks.
- Crown-rump length is the best surrogate measure of gestational age.
- Pregnant women who present at or beyond 14 weeks of gestation should be offered an ultrasound scan to estimate gestational age using head circumference or biparietal diameter.
- If a health professional is involved at this stage they should check if the woman has been taking folic acid and advise as appropriate.
Frequency and number of antenatal assessments in uncomplicated pregnancies
- Nulliparous patients with uncomplicated pregnancies should be seen over a schedule of ten appointments.
- Parous women with uncomplicated pregnancies should be seen over a schedule of seven appointments.
The first antenatal appointment
NICE recommends that the first antenatal appointment take place early in pregnancy (before 12 weeks) and that it may need to be booked as a double appointment due to the large amount of information and assessments that are required. The checklist below covers those areas that are considered important by NICE:
- Give mother information on her antenatal care and an opportunity to ask any questions/raise any concerns. Consider topics such as:
- All women should be informed at the booking appointment about the importance, for their own and their baby's health, of maintaining adequate vitamin D stores during pregnancy and whilst breast-feeding.
- 10 micrograms of vitamin D per day should be taken by women at risk. These include:
- Women of South Asian, African, Caribbean or Middle Eastern family origin.
- Women who have limited exposure to sunlight, such as women who are predominantly housebound, or who usually remain covered when outdoors.
- Women who eat a diet particularly low in vitamin D, such as women who consume no oily fish, eggs, meat, vitamin D-fortified margarine or breakfast cereal.
- Women with a pre-pregnancy body mass index (BMI) above 30 kg/m2.
- Available pregnancy care services.
- Maternity and associated benefits.
- Working and finishing work when pregnant.
- Availability, purpose and logistics of screening tests in pregnancy.
- Identify women who may need special care (see list below under 'Criteria for more specialised care'; plan pattern of care for pregnancy depending on parity/previous complications of pregnancy.
- Check blood group and rhesus (RhD) status.
- Offer blood test to screen for:
- Red-cell alloantibodies.
- Hepatitis B.
- Rubella immunity status.
- Syphilis serology.
- Screening for sickle cell diseases and thalassaemias should be offered to all women as early as possible in pregnancy (ideally by 10 weeks). The type of screening depends upon the prevalence and can be carried out in either primary or secondary care.
- Urine testing to screen for asymptomatic bacteriuria.
- The 'combined test' (nuchal translucency, beta human chorionic gonadotrophin (beta-hCG), pregnancy-associated plasma protein-A) should be offered to screen for Down's syndrome between 11 weeks 0 days and 13 weeks 6 days. For women who book later in pregnancy, the most clinically effective and cost-effective serum screening test (triple or quadruple test) should be offered between 15 weeks 0 days and 20 weeks 0 days.
- Offer early ultrasound scan to assess gestational age.
- Screening for gestational diabetes, using risk factors, is recommended in a healthy population. Women with any one of these risk factors should be offered testing for gestational diabetes at the booking appointment:
- BMI above 30 kg/m2.
- Previous macrosomic baby weighing 4.5 kg or above.
- Previous gestational diabetes.
- Family history of diabetes (first-degree relative with diabetes).
- Family origin with a high prevalence of diabetes:
- South Asian (specifically women whose country of family origin is India, Pakistan or Bangladesh).
- Black Caribbean.
- Middle Eastern (specifically women whose country of family origin is Saudi Arabia, United Arab Emirates, Iraq, Jordan, Syria, Oman, Qatar, Kuwait, Lebanon or Egypt).
- Offer 20-week ultrasound screening for fetal anomaly.
- Measure BMI.
- Check and record blood pressure (BP).
- Test urine for glycosuria/proteinuria.
For a full schedule of assessments at each of the antenatal assessments and what areas they should cover, see NICE guidance.
Routine antenatal pelvic examination does not accurately assess gestational age, nor does it accurately predict preterm birth or cephalopelvic disproportion. It is not recommended.
Routine breast examination is not recommended.
The patient should be weighed and her height measured so that her body mass index can be calculated as:
- BMI = weight in kilograms/(height in metres)2.
- This can be used as a baseline for future weighing where it is clinically indicated.
- Test for asymptomatic bacteriuria early in pregnancy using dipstick testing; send mid-stream specimen of urine (MSU) if indirect test is positive.
- Test for proteinuria every time BP is taken.
- Check for glycosuria at every visit; if more than 2 then test random plasma venous glucose and determine need for an oral glucose tolerance test on the basis of that result; there is no evidence of benefit from routine screening for gestational diabetes mellitus. See separate article Glucose Tolerance Tests.
- Measure BP at presentation and at every subsequent appointment.
- Assess risk factors for pre-eclampsia:
Schedule further appointments accordingly to allow appropriate monitoring of BP.
Enquire into the areas listed below, and ask about any previous significant physical or psychiatric illness. Women with a history of significant psychiatric illness should be offered a referral to psychiatric services to screen for problems, and for advice on appropriate support:
- Occupation for any associated risks.
- Alcohol and recreational drug use.
- Domestic violence.
- Psychiatric illness.
Advise and refer accordingly if any areas of concern come to light.
- Offer estimation of fetal size by measuring symphysis-fundal distance at each examination to look for a fetus that is small or large for gestational age.
- After 36 weeks, palpate the abdomen for possible malpresentation and confirm with ultrasound scan if suspected.
Offer an ultrasound examination early in pregnancy (preferably at 10-13 weeks) to:
- Determine gestational age.
- Detect multiple pregnancies.
- Help with later screening for Down's syndrome.
- At 11-14 weeks, offer nuchal translucency screening for Down's syndrome, with other tests if available.
- At 18-20 weeks, offer screening with ultrasound for congenital anomalies.
- If the placenta is over the cervical os, offer a scan, at 36 weeks, for placenta praevia.
Criteria for more specialised care
The triennial confidential report of maternal and child health identifies many high-risk scenarios in pregnancy. Although the following list is not exhaustive, these conditions can be associated with more adverse outcomes and warrant specialist opinion:
- Cardiac disease, including hypertension.
- Renal disease.
- Diabetes treated with insulin, or any other endocrinological disorder.
- Treated psychiatric disorder.
- Haematological disease including propensity to thromboembolism and autoimmune disorder, such as antiphospholipid syndrome.
- Epilepsy requiring anticonvulsant therapy.
- Any current or recently treated malignant disease.
- Significant respiratory impairment, including severe asthma.
- Problematic alcohol use.
- Regular/problematic use of recreational drugs such as heroin, cocaine, crack, ecstasy, etc.
- Chronic viral infections, eg HIV, hepatitis B virus (HBV), hepatitis C virus (HCV).
- Autoimmune disorders.
- Previous uterine surgery including Caesarean section, myomectomy or cone biopsy.
- BMI <18 or >30 kg/m2.
- Women at higher risk of complications during pregnancy, eg older than 40 years, smokers, very young mothers, those without social support.
- Problems associated with previous pregnancies:
- Recurrent miscarriage (>3 consecutive pregnancy losses or a mid-trimester loss).
- Preterm birth.
- Severe pre-eclampsia, HELLP syndrome (= H aemolysis, EL (elevated liver) enzymes, LP (low platelet) count) or eclampsia.
- Rhesus isoimmunisation or other significant blood group autoantibodies.
- Previous antepartum haemorrhage or postpartum haemorrhage on two occasions.
- Retained placenta on two occasions.
- Puerperal psychosis.
- Grand multiparity (>6 children).
- Previous stillbirth or neonatal death.
- Small-for-gestational-age infant (<5th centile).
- Large-for-gestational-age infant (>95th centile).
- Baby weighing <2.5 kg or >4.5 kg.
- Baby with a structural or chromosomal anomaly.
Further reading & references
- Antenatal care; NICE Clinical Guideline (March 2008)
- Ahmed S, Green J, Hewison J; What are Pakistani women's experiences of antenatal carrier screening for beta-thalassaemia in the UK? Why it is difficult to answer this question? Public Health. 2002 Sep;116(5):297-9.
- NHS Sickle Cell and Thalassaemia Screening Programme; Public Health England
- Fetal Anomaly Screening Programme - Policy recommendations, UK National Screening Committee, 2007-2010
- Domestic violence: A resource manual for health care professionals, Dept of Health, March 2000
- Saving Mothers' Lives. Reviewing maternal deaths to make motherhood safer: 2006-2008; Centre for Maternal and Child Enquiries (CMACE), BJOG, Mar 2011
- Alcohol Consumption and the Outcomes of Pregnancy; Royal College of Gynaecologists, March 2006
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.
Dr Sean Kavanagh
Dr Hayley Willacy
Dr Colin Tidy