Clinics in obstetrics and gynaecology最新文献

• 1.

  Prostaglandins, particularly PGE₂ vaginally, can be valuable for cervical ripening or induction of labour in some women. Ease of use must not be allowed to result in unjustified intervention.

• 2.

  Amniotomy followed by oxytocin infusion are the methods of choice for induction of labour. Careful monitoring of the maternal and fetal condition are vital, especially if an epidural block is in place.

• 3.

  Augmentation of labour is only appropriate for inefficient primigravid labour. Failure to progress in a multiparous woman is more likely to be due to obstruction.

• 4.

  Low residue, easily digested foodstuffs are not necessarily contraindicated during normal labour.

• 5.

  When properly used, Entonox can provide analgesia equivalent to 75–100 mg pethidine.

• 6.

  Sodium citrate is the antacid of choice during labour and should be combined with an H₂-receptor blocking agent for caesarean section, or other procedure involving anaesthesia.

• 7.

  The routine injection of Syntometrine at delivery of the anterior shoulder to prevent PPH is widespread in the UK but has not been properly tested. Oxytocics are invaluable in the treatment of PPH.

Hypertensive diseases are among the most common of all pregnancy complications. Significant elevations of blood pressure can be missed if inflexible criteria are used. There is now very strong evidence to support the use of antihypertensive agents in all forms of hypertension. The antihypertensive drugs in current use have a good safety record with regard to both mother and baby. The management of hypertension during pregnancy ideally requires the close cooperation of obstetrician and physician.

When treating thyroid disease, as with other conditions in pregnancy, one is concerned with the welfare of both mother and developing child. Thyroid disease causes few maternal problems; thyrotoxicosis in fact tends to improve in pregnancy, allowing medical management with lower drug doses than usual. Relapse of thyroid disease may occur postpartum, when transient hypo- and hyperthyroidism are relatively common.

In contrast, the fetus and neonate are threatened in a number of ways by drugs given to the mother and by transplacental passage of maternal antibodies capable of inducing thyroid disease.

Antithyroid drugs may cause fetal goitre with airway obstruction, and are associated with mild neonatal hypothyroidism. Thyroid antibodies in primary myxoedema and Hashimoto's thyroiditis are occasionally implicated in neonatal hypothyroidism and may even cause thyroid dysgenesis. Neonatal hyperthyroidism has a high morbidity and mortality and may have long-term skeletal effects such as craniosynostosis.

Fetal problems may not be apparent at birth but may emerge in the next eight to ten days, especially in hyperthyroidism when the mother has been on treatment. Close monitoring throughout pregnancy and for the first ten days postpartum is required to minimize risks to the fetus and neonate. Most pregnancies associated with thyroid disease will have a successful outcome. If the occasional at-risk fetus is to be identified and treated successfully there should ideally be close cooperation between obstetrician, endocrinologist and paediatrician.

Thromboembolic disorders are still a serious problem in pregnancy and anticoagulants have an important part to play in both treatment and prevention.

Warfarin is the most convenient drug to give but can cause maternal and fetal bleeding problems, especially during late pregnancy and delivery. There are also small risks of embryopathy from warfarin in early pregnancy but these may have been overstated. Heparin, which has to be given parenterally, does not cross the placental barrier but can still cause bleeding problems in pregnancy. Full intravenous heparin is only suitable for short-term use, and subcutaneous heparin has been introduced for long-term therapy. This regimen is a useful advance but long-term use still has problems of bruising and maternal bone demineralization.

The standard treatment of acute thromboembolic events in pregnancy is continuous intravenous heparin followed by either subcutaneous heparin or warfarin, the latter being changed at 36 weeks gestation. In the prophylaxis of thromboembolism, the trend istowards a more selective approach, anticoagulants being given during pregnancy to those at highest risk and during labour and the puerperium to all with a previous history of thromboembolism. Anticoagulants during pregnancy are necessary in patients with artificial heart valves and, because subcutaneous heparin is not sufficient, warfarin should be used until 36 weeks followed by continuous intravenous heparin until delivery.

No method of anticoagulation during pregnancy is entirely free of risk and all management policies must be based on an estimate of risk-benefit ratio in individual patients.