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N MacLachlan

Publications and source records attributed to N MacLachlan.

8 recordsLinked to original sources

Umbilical cortisol levels as an indicator of the fetal stress response to assisted vaginal delivery.

OBJECTIVES: While it is well established that delivery by elective caesarean section is less stressful for the fetus than normal vaginal delivery, little attention has been paid to the effect on the baby of an assisted delivery. STUDY DESIGN: We examined cortisol levels in venous cord blood from seven babies born by forceps, 10 by ventouse extraction, 28 by unassisted normal vaginal delivery, and 12 born by elective caesarean. Paired maternal bloods were taken immediately after delivery. RESULTS: Cord blood cortisol values were significantly different in the different groups (one-way ANOVA, P < 0.0001). The forceps group had the highest values and the caesarean group the lowest; both were different from the normal vaginal delivery group (P=0.019 and P=0.046, respectively). There was no effect of length of labour, or method of pain relief on cortisol levels. Maternal values were similar in the different groups, confirming that the differences observed derived from the fetus. CONCLUSIONS: There is increasing evidence that the stress experienced by the fetus or neonate can have long-term effects on the function of the hypothalamic-pituitary-adrenal axis in later life. We speculate that the stress caused by some assisted deliveries may contribute to this.

Cesarean Section↗

Ultrasound markers of fetal chromosomal abnormality: a survey of policies and practices in UK maternity ultrasound departments.

OBJECTIVE: To evaluate the management of pregnancies where the fetus was found to have one or more sonographic markers of possible fetal chromosomal abnormality. DESIGN: Prospective anonymous postal survey of UK obstetric ultrasound units. MAIN OUTCOME MEASURES: The management of pregnancies where the fetus is found to have a sonographic marker of aneuploidy. POPULATION: All 252 maternity ultrasound units in the United Kingdom. METHODS: Postal questionnaire to the superintendent sonographer in routine maternal ultrasound departments. RESULTS: Questionnaires were returned from 179 maternity units (71%). Of the respondents 94% offered a fetal anomaly scan at 16-20 weeks' gestation and 59% performed a dating scan at 10-14 weeks. Screening for Down syndrome was available in 99% of all maternity units. The recognition of sonographic 'soft signs' for possible fetal chromosomal abnormality varied considerably between the units. When sonographers were asked about their unit's policy regarding offering amniocentesis to women with sonographic markers, 8-78% discussed amniocentesis when the marker was isolated and 53-88% when another abnormality was found. Eighty nine percent of units documented the abnormal ultrasound findings in the hospital notes and 88% of the women were informed of the findings regardless of the intention to offer amniocentesis. CONCLUSION: The practice of routine ultrasound examination is well established in UK, though precise policies vary. The existing wide variations in management policies possibly reflect a lack of data derived from low risk populations. There is a need to collect such data from low risk populations with known screening practices so that national guidelines to standardize practice can be formulated.

Amniocentesis↗

Extraction of DNA from amniotic fluid cells for the early prenatal diagnosis of genetic disease.

Ten-ml samples of amniotic fluid were taken from pregnancies being terminated at 8-14 weeks' gestation. DNA was extracted from the amniotic cells by sequential centrifugation and analysed using the polymerase chain reaction (PCR). Fifteen samples were analysed for evidence of maternal contamination using Mfd5 oligonucleotide primers for repeat polymorphisms. Ten amniotic fluid samples were tested for the Delta-F508 deletion characteristic of cystic fibrosis to demonstrate a diagnostic application for the technique. In each case, DNA extracted from fetal tissue from the same pregnancy was included in the controls. In 14 of the 15 cases tested with the Mfd5 primers, both the amniotic fluid DNA and the fetal DNA showed no evidence of contaminating DNA. In one case, neither the amniotic fluid cells nor the fetal cells yielded results. In nine of the ten cases tested with the Delta-F508 primers, the amniotic fluid cell DNA provided accurate information about the genetic status of the fetus; in the tenth, the fetal DNA failed to amplify. The results indicate that adequate DNA can be extracted from amniotic fluid from 8 weeks' gestation onward and these samples are suitable for prenatal diagnosis using PCR.

Adult↗

Budd Chiari syndrome, visceral arterial occlusions, recurrent fetal loss and the "lupus anticoagulant" in systemic lupus erythematosus.

A 30-year-old Chinese woman had been diagnosed as having systemic lupus erythematosus (SLE) at age 25 after 4 spontaneous abortions, all between 8 and 12 weeks of gestation. A year later she developed mild jaundice and at laparotomy, nodular enlargement of the right lobe of the liver and splenomegaly were seen. She was found to have a "lupus anticoagulant" and false positive test for syphilis (VDRL), but persistently negative antibodies to cardiolipin. Angiography demonstrated occlusion and stenoses of visceral abdominal arteries and hepatic venography also showed evidence of hepatic venous occlusions. She subsequently developed thyrotoxicosis which was treated with carbimazole, followed by radioactive iodine. The SLE and lupus anticoagulant were treated with systemic steroids (prednisolone) and anticoagulation (warfarin).

Abortion, Spontaneous↗

SLE and pregnancy.

In patients with SLE in remission pregnancy does not confer a special risk to either the mother or foetus, and immunoregulatory drugs should not be withdrawn prior to a pregnancy where these are required for disease control. Likewise therapy to treat disease flares during pregnancy should not be withheld as the foetus is at comparitively more risk from the effects of the maternal disease than from the small risk associated with therapy. Patients with active disease should be counselled against pregnancy but therapeutic abortion in such patients is only very rarely indicated. High risk groups benefit from close monitoring though the previous obstetric history will not necessarily reflect outcome in subsequent pregnancies. Patients without a previous obstetric history should not be treated prophylactically due to the detection of antiphospholipid antibodies, and the optimum treatment for those with poor histories and aPL is currently being investigated.

Female↗