Anne B. M. Anderson

RELATION BETWEEN MEASURED MENSTRUAL BLOOD LOSS AND PATIENT'S SUBJECTIVE ASSESSMENT OF LOSS, DURATION OF BLEEDING, NUMBER OF SANITARY TOWELS USED, UTERINE WEIGHT AND ENDOMETRIAL SURFACE AREA

In 92 women complaining of heavy but regular periods for which no cause was found, the relation was studied between measured menstrual blood loss during two consecutive periods and the patients subjective assessment of blood loss, the number of days of bleeding, and the number of sanitary pads and tampons used. There was no correlation between menstrual blood loss and these parameters. In many women these parameters are not a reliable indicator of the volume of menstrual blood loss. In 40 of the 92 women, who subsequently had a hysterectomy because of their complaint of menorrhagia, the uterus was weighed and the endometrial surface area measured. The view that menorrhagia is associated with a large uterus or a large endometrial surface area could not be confirmed.

Factors associated with spontaneous pre-term birth

Factors associated with spontaneous pre‐term birth in 283 singleton pregnancies were compared with those present in a total population of 16 994 women at risk studied in the First British Perinatal Mortality Survey. It was shown that the risk of spontaneous pre‐term birth was related to low maternal age, low maternal weight, maternal smoking, low social class, illegitimacy, threatened abortion, and a previous history of antepartum haemorrhage, perinatal loss, or low birth weight livebirths.

MEASUREMENT OF MENSTRUAL BLOOD LOSS IN PATIENTS COMPLAINING OF MENORRHAGIA

A study has been made of menstrual blood loss measured in 50 women with unexplained heavy loss (more than 80 ml). Twelve of these women had an average menstrual loss greater than 200 ml, five women in excess of 450 ml. There was no relation between the duration of menstruation and the total menstrual blood loss. Compared to women with normal menstrual loss there was no difference either in the proportion of total menstrual loss passed on each day of menstruation in women bleeding heavily (92 per cent of the total menses being lost in the first three days) or in the coefficient of variation for menstrual blood loss from one period to the next. There was a reduction in menstrual blood loss in the first period following uterine curettage but no effect thereafter.

11β-hydroxysteroid dehydrogenase activity (E.C. 1.1.1.146) in human placenta and decidua

Abstract 11β-Hydroxysteroid dehydrogenase activity (E.C. 1.1.1.146) was studied in homogenates of placenta, fetal membranes and decidua obtained at term, using cortisol and cortisone as substrates. For activity in the direction cortisol to cortisone, the distribution of enzyme was choriodecidua > placenta. While choriodecidua catalysed the conversion in both directions, cortisone reduction was negligible in placenta. Amnion contained no measurable enzyme, using either substrate. The activity in the choriodecidua was thought to be of decidual rather than chorionic origin. In both decidua and placenta, the enzyme was localised by subcellular fractionation in the microsomal fraction, and microsomal fractions were used to study the dependence of activity on pH, substrate and enzyme concentration and the inhibitory effect of other steroids. Data on the K M values for cortisol and the inhibition of the enzyme by some steroids, notably androgens, suggest that the enzymes in decidua and placenta may be different. The findings are discussed in relation to the possible role of the enzyme in the control of fetal corticosteroid concentrations.

Prostaglandins in menstrual fluid in menorrhagia and dysmenorrhoea

Menstrual fluid was collected in vaginal cups inserted for 2 h during the first 2 days of menstruation and menstrual serum concentrations of prostaglandins PGF2α and PGE2 were measured by radio‐immunoassay. In 16 women from whom menstrual fluid was collected on both days, PGF2α and PGE2 concentrations were significantly higher on day 1 than on day 2. The highest concentrations of PGF 2α and PGE2 were found in dysmenorrhoeic women on day 1. In non‐dysmenorrhoeic women, the amount of PGF2α and PGE2 collected in 2 h correlated directly with total menstrual blood loss. There was no statistically significant difference in the amount of prostaglandins collected in 2 h in pain‐free menorrhagic women and dysmenorrhoeic women with normal loss. There was also no significant 9‐ketoreductase or 9‐hydroxydehydro‐genase activity present in menstrual fluid which could suggest PGE2 to PGF2α interconversion.

THE IN VITRO PRODUCTION OF PROSTANOIDS BY THE HUMAN CERVIX DURING PREGNANCY: PRELIMINARY OBSERVATIONS

The ability of the pregnant human cervix to produce prostanoids has been studied using an in vitro superfusion technique. Tissues obtained from four patients during the first trimester of pregnancy produced prostaglandin E (PGE), prostaglandin F (PGF), 13,14‐dihydro‐15‐oxo‐prostaglandin F (PGFM) and 6‐oxo‐prostaglandin F2α (6‐oxo‐PGF1α). Production of thromboxane B2 (TXB2) was minimal. Preliminary studies using tissue taken at Caesarean hysterectomy during the last trimester of pregnancy indicate that the cervix may show increased prostanoid production during active dilatation. The implications of these observations for an involvement of prostanoids in cervical softening during human parturition are discussed.

REDUCTION BY MEFENAMIC ACID OF INCREASED MENSTRUAL BLOOD LOSS ASSOCIATED WITH TNTRAUTERINE CONTRACEPTION

Twenty‐five healthy parous women using intrauterine contraceptive devices (IUCDs) received mefenamic acid, 500 mg 8‐hourly, during two menstrual periods. Two pre‐ and two post‐treatment menses were similarly studied, by the collection of used sanitary pads and/or tampons and measurement of daily blood loss. A highly significant reduction in mean total blood loss during the treatment periods was observed, unaffected by whether therapy began on the first day of bleeding or in the late luteal phase. The reduction was observed among both inert and copper‐containing IUCD‐users. Expressed as a percentage of the mean pre‐treatment volume, the reduction in loss was not significantly different for those IUCD‐users who were light losers (less than 80 ml) compared with heavy losers (80 ml or more), but it was greater in volume terms among the latter. The amounts lost during the post‐treatment periods, whether or not placebo tablets were given, were not significantly different from pre‐treatment. Reports of side effects were infrequent. By contrast with the reduction in volume lost, no effect of mefenamic acid on the total duration of bleeding and non‐collectable spotting’could be demonstrated.

REDUCTION OF MENSTRUAL BLOOD LOSS BY DANAZOL IN UNEXPLAINED MENORRHAGIA: LACK OF EFFECT OF PLACEBO

In women with menorrhagia of unknown cause, the efficacy of the drug danazol in reducing heavy menstrual blood loss was investigated making objective measurements of menstrual blood loss. Drug regimens tested were daily administration of 200 or 100 mg danazol for 12 weeks and daily danazol given in the luteal phase or during menstruation. The results suggest that 200 mg danazol daily is the most acceptable regimen clinically since it significantly reduced menstrual blood loss and was associated with a relatively low incidence of side effects. In 16 women on this dose menstrual blood loss was suppressed from a mean pre‐treatment loss of 183±25ml to 38±11 ml (p<0.01) in the second, and 26±9 ml (p<0.01)in the third treatment months. The majority of women had regular episodes of bleeding with no alteration in cycle length and a reduction in the number of days of bleeding. Although 100 mg daily suppressed menstrual blood loss, particularly by the third month of treatment, it increased the number of episodes of bleeding in some women which they found unacceptable. Both 200 mg and 100 mg relieved dysmenorrhoea in the majority of women presenting with the symptoms. Danazol taken daily in the early follicular or luteal phase of the menstrual cycle did not significantly alter menstrual blood loss. There was no effect of placebo therapy on measured menstrual blood loss in a single blind trial in eight women with menorrhagia.

A retrospective study of induction of labour.

The labour, delivery and state of the newborn were compared retrospectively in a group of women who had labour induced and a group who started labour spontaneously. There were 200 women at term in each group, individually matched for age, parity and social class and with no medical or obstetric complications prior to labour. The induced group showed a higher incidence of epidural anaesthesia, fetal monitoring and operative delivery. Sixty had forceps deliveries and five had Caesarean sections compared with two forceps deliveries and no Caesarean sections in the ‘spontaneous onset’ group. The higher incidence of operative deliveries in the induced group was not fully explained by the excess of epidurals and fetal monitoring received. More of the babies born after an induced labour had endotracheal intubation during resuscitation.

Is oxytocin involved in parturition

Peripheral plasma levels of oxytocin were determined in women during pregnancy and labour. There was a significant increase in maternal plasma oxytocin with advancing gestation but no significant change in levels at any stage of labour. Oxytocin concentrations in umbilical cord plasma were measured after spontaneous vaginal delivery and at elective caesarean section. A significant arteriovenous difference, with higher arterial levels, was found in both groups and the values after labour were significantly higher than at elective caesarean section. These findings suggest that the fetus is able to produce oxytocin which may play a role in human parturition.