O. A. C. Viegas

Implanon® contraceptive implants: effects on carbohydrate metabolism

The objective of the study was to assess the possible differences in effects of Implanon and Norplant implants on carbohydrate metabolism. This is a 2-year open randomized study of 80 implant (Implanon and Norplant) acceptors. Oral glucose tolerance test (OGTT) was performed before implant insertion and at 6, 12, and 24 months after implant insertion. Glycosylated hemoglobin A(1)C was measured in fasting samples and plasma samples during OGTT were tested for glucose and insulin levels. There was a significant increase in the area under the curve for both glucose and insulin during OGTT within each group with increasing duration of use. However, there was no significant change in the fasting plasma glucose values. There was no significant difference in the carbohydrate parameters between the two groups during implant use, except for a minimal but statistically significant rise in fasting glycosylated hemoglobin A(1)C levels at 24 months in the Implanon group. Both implants appear to induce mild insulin resistance but no significant change in serum glucose levels. These alterations in carbohydrate metabolism should have no clinical significance in healthy women.

Effect of Implanon and Norplant subdermal contraceptive implants on serum lipids -- a randomized comparative study.

The objective of this study was to assess the possible differences in effects of Implanon (etonogestrel 68 mg, single-rod) and Norplant (levonorgestrel 36 mg, six capsules) implants on serum lipids over 2 years of use. In this 2-year open randomized study of 80 implant acceptors, selected serum lipids were tested before implant insertion and at 6, 12 and 24 months after implant insertion. The lipid parameters evaluated were: total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides, apolipoprotein A-I and apolipoprotein B. During the 2 years, the serum lipid pattern in the Implanon users was not significantly different from that of the Norplant users. There was slight decrease in HDL-C levels in both the groups but there were no significant changes in the HDL/TC ratio and the HDL/LDL ratio. Although it was statistically significant, the magnitude of decrease in HDL-C from preinsertion levels in Implanon users was only 5.8% at the end of 2 years.

Plasminogen activators and inhibitors in normal late pregnancy, postpartum and in the postnatal period.

Tissue plasminogen activator (t‐PA), urokinase plasminogen activator (u‐PA) and plasminogen activator inhibitors (PAI) are elevated in late pregnancy with t‐PA and u‐PA remaining so at 6 weeks postnatal. PAI‐2 remains at postpartum but was absent by 6 weeks postnatal unlike PAI activity which was absent at postpartum and returned to nonpregnant level at postnatal. The potential fibrinolytic response to stress is much reduced in pregnancy thus increasing the risk of thromboembolism.

Effect of Implanon® use on selected parameters of thyroid and adrenal function

In this article, the effects of Implanon implant use on thyroid and adrenal function was compared with those of Norplant implants. In this 2-year open randomized study of 80 implant acceptors, we found that both implants may induce minimal changes in thyroid hormones and cortisol levels, possibly secondary to alterations in the respective binding globulins in the serum. These alterations in thyroid and adrenal function would have no clinical significance in healthy women. In the Norplant group, sex hormone-binding globulin levels decreased, whereas increased levels were found in the Implanon users at the end of 2 years. These findings lend support to the fact that etonogestrel, released from Implanon implants, is significantly less androgenic than levonorgestrel, released from the Norplant implants.

Symptomatic gastro-oesophageal reflux in pregnancy: A prospective study among Singaporean women

The present study was undertaken to estimate the prevalence and time course of reflux‐type symptoms in Singaporean women and to determine if these symptoms were associated with nausea and vomiting of pregnancy. Consecutive pregnant women in the first trimester of pregnancy were recruited during attendance at an antenatal clinic in a Singapore teaching hospital. Each was interviewed, using a reliable questionnaire detailing demographic characteristics and symptoms, at four time points during the first, second and third trimesters of pregnancy and postpartum period. A total of 35 of 47 women originally enrolled (response rate 74%) completed the study. Heartburn alone, acid regur‐gitation alone and both heartburn and acid regurgitation were reported by 5.7, 17.1 and 17.1% of the subjects, respectively. Subjects who had these symptoms were more likely to suffer daily nausea and/or vomiting (78.6%) than those who did not (33.3%, P < 0.05). In the majority of subjects, heartburn and/or acid regurgitation began in the first trimester (78.6%) and disappeared during the second trimester (71.4%). Nausea alone and in combination with vomiting similarly came on in the first trimester (100%) and subsided by the second trimester (85.7%) in the majority of the subjects studied. The reported prevalence of heartburn and/or acid regurgitation among Western pregnant women were 48–96% and 62%, respectively. Our data, therefore, showed that reflux‐type symptoms were less common in Singaporean pregnant women. Reflux‐type symptoms were related to nausea and vomiting, both in frequency and time pattern of onset and disappearance of symptoms. The association suggested either a common mechanism or a cause and effect relationship.

Effect of Norplant®-2 rods on haemostatic function

A longitudinal study on one-hundred Singaporean women using Norplant-2 rod implant for contraception and their effects on the haemostatic function was carried out. There was a decrease in vitamin K-dependent Factors II, VII and a tendency towards lowered fibrinolytic activity after prolong use of Norplant-2 rods. The results indicate that the Norplant-2 rod implant system does not contribute towards hypercoagulable state but increased platelets and accelerated platelet aggregation observed will require further study to ascertain whether there is a concomitant increase in platelet activation.

Nile stimulation in late pregnancy causing uterine hyperstimulation and profound fetal bradycardia

Nile stimulation in late pregnancy may cause oxytocin release sufficient to give uterine hypertonus and danger to the fetus. Three patients are described in whom nile stimulation caused a marked but temporary fetal bradycardia.

Malignant melanoma of the cervix.

Primary malignant melanoma of the cervix was diagnosed in a 52-year-old woman. Extended hysterectomy and partial vaginectomy were performed. A vulval recurrence was treated with wide excision and total vaginectomy. She subsequently underwent radiotherapy for metastatic lesions in the pelvis and para-aortic nodes, but succumbed to widespread metastatic disease 2 years after initial diagnosis. Diagnosis, therapy, and prognosis for malignant melanoma are discussed.

Obstetrical outcome with increasing maternal age

A retrospective study of 21,442 Singaporean women who gave birth at the National University Hospital, Singapore, between January 1986 and November 1991 is used to assess the effects of increasing age on obstetric performance. The results show that reproduction after the age of 35 years in Singapore is associated with a higher incidence of antenatal complications such as hypertension and diabetes and a higher rate of obstetric intervention. However, given the current level of obstetric and neonatal care in Singapore, these adverse features do not prejudice the obstetric and neonatal outcomes.

Pregnancy outcome in unmarried teenage nulligravidae in Singapore

Singapore, like other newly industralized countries, has seen a dramatic transformation in the social standards of its population in a particularly short space of time. Unfortunately, this period of development has been accompanied by an escalation in the number of pregnancies to unmarried teenage girls. This paper examines the obstetric and social implications of 150 such pregnancies in younger and older teenagers. Poor intrauterine growth in the younger teenager appears to be the most important adverse obstetric outcome in that mean birthweight was significantly reduced (2738 g compared to 3054 g; P < 0.02). We believe this to be an important explanation for the five‐fold increase in perinatal mortality seen in this group of mothers. Unlike some other reports, we found no significant increase in the incidence of cephalopelvic disproportion, anemia or pregnancy induced hypertension in these mothers. The social implications of teenage pregnancy in Singapore are also examined and recommendations made for methods to curb the problem