Thomas Walsh

Laboratory assessment of iron status in pregnancy.

Abstract Background: Efforts to improve maternal nutrition during pregnancy prompted an observational study of the occurrence of maternal iron deficiency and its laboratory diagnosis in almost 500 pregnancies. Methods: In this longitudinal study, the biochemical and haematological iron indices of women (n=492) attending a prenatal clinic in a Dublin maternity hospital were assessed at first booking (mean 15.9 weeks), and after 24 weeks, and 36 weeks of gestation. Full blood counts were measured. Serum ferritin (SF), zinc protoporphyrin (ZPP), and transferrin receptor (sTfR) concentrations were assayed and transferrin receptor index (sTfR-Index) was calculated. The occurrence of low values and their diagnostic values were considered. Results: A high occurrence iron deficiency (ID) at first booking (SF<12 μg/L) had increased over six-fold by 24 weeks, and all biochemical iron indices reflected progressive iron depletion right up to term. The WHO recommended anaemia “cut-off” (Hb<110 g/L) was insensitive to biochemical iron deficiency at booking, missing over 90% of the low SF values (SF<12 μg/L) which were mostly associated with much higher Hb levels. Conclusions: This study stresses the importance of including a biochemical index of iron status in prenatal screening and supports SF as the best indicator of biochemical ID overall. sTfR was insensitive to iron deficiency in early pregnancy, whereas the sTfR-Index, as a ratio, has the potential to distinguish between ID and physiological anaemia, and may offer stability in the assessment of iron stores from early pregnancy to full term. A policy of early screening of both Hb and SF concentrations is recommended as the minimum requirement for surveillance of maternal iron status in pregnancy.

Illegal drug use, smoking and alcohol consumption in a low-risk Irish primigravid population.

Abstract To evaluate the prevalence of illegal drug use, smoking and alcohol consumption in Irish primigravidas, we interviewed 1011 women at their booking visit. A total of 23.5% (235) of women had used illegal drugs prior to their first pregnancy, 28.9% were ex-smokers and 27.9% were still smoking during pregnancy. A total of 53.9% admitted to drinking alcohol during pregnancy. Smokers are 2.8 times more likely to have used drugs in the past than non-smokers. Level of alcohol consumption appears to be a significant predictor of drug use.

The incidence and impact of increased body mass index on maternal and fetal morbidity in the low-risk primigravid population.

Objective. To determine the incidence and impact of increased body mass index (BMI) on maternal and fetal morbidity in the low-risk primigravid population. Methods. This was a prospective study with retrospective analysis of delivery outcome data. All low-risk primigravida who met the inclusion criteria during the recruitment period were approached. BMI was calculated using the formula weight/height squared. The participants were divided into five categories: ‘underweight’ (BMI <20 kg/m2), ‘normal’ (BMI 20.01–25 kg/m2), ‘overweight’ (BMI 25.01–30 kg/m2), ‘obese’ (BMI 30.01–40 kg/m2), and ‘morbidly obese’ (BMI >40 kg/m2). Maternal outcomes evaluated included gestation at delivery, onset of labor (spontaneous/induced/elective cesarean section), length of labor, use of oxytocin and epidural, mode of delivery, and estimated blood loss. Perinatal outcome measures included infant birth weight (kg) and centile, gestational age, ponderal index, Apgar score <7 at 5 minutes, cord pH <7.1, presence of meconium grade 3 at delivery, degree of resuscitation required, admission to neonatal intensive care unit (NICU), and duration of stay. Results. One thousand and eleven women participated in the study. Complete outcome data were available for 833 women (82%). A significant difference was identified in gestation at delivery between the subgroups (p < 0.004). A significant positive correlation was identified between cesarean section rates with increasing BMI, even when gestation was controlled for (p = 0.004). Similarly, women in the normal BMI group remained significantly less likely to have an infant requiring NICU admission than obese women (2.2% vs. 8.6%; p = 0.011). Conclusion. High BMI is associated with longer gestations, higher operative delivery rates, and an increased rate of neonatal intensive care admission.

The impact of ultrasonographic placental architecture on antenatal course, labor and delivery in a low-risk primigravid population

Objective. To ascertain the impact of placental architecture on antenatal course and labor delivery in a low-risk primigravid population. Methods. This study involves prospective recruitment of 1011 low-risk primigravids with placental ultrasound at 22–24 weeks and 36 weeks. Detailed postnatal review of all mothers and infants was undertaken. Retrospective analysis of ultrasound and clinical outcome data was performed. Results. Eight hundred ten women with complete outcome data were available. Anterior placentation was statistically associated with intrauterine growth restriction (IUGR) and preterm birth and fundal placentation was significantly associated with a higher incidence of pregnancy-induced hypertension and infants with a birthweight less than the 9th centile. Placental infarcts in the third trimester was significantly increased in cases complicated by pre-eclampsia (PET) and in cases with fetal acidosis. Placental calcification was associated a 40-fold increase in the incidence of IUGR. Placental lakes in the second trimester were more prevalent in patients with threatened miscarriage. Increased placental thickness was associated with a higher rate of fetal acidosis. The Grannum grade of the placenta was higher with threatened first or second trimester loss, PET and in infants born less than 9th centile for gestation. Conclusion. Placental site and architecture impact on the incidence of maternal and fetal disease.

Successful pregnancy after rituximab in a women with recurrent in vitro fertilisation failures and anti-phospholipid antibody positive

We report a case of successful pregnancy after rituximab in a patient with a history of in vitro fertilisation (IVF) failures and positive anti-cardiolipin antibody (ACA). Following a course of rituximab, her ACA became negative and she successfully conceived with IVF treatment. This is the first case in literature describing the use of rituximab therapy in this clinical scenario.

The relationship between body mass index and mid-arm circumference in a pregnant population

Our objective was to correlate body mass index (BMI) with mid-arm circumference (MAC) and also to ascertain whether maternal BMI could be calculated from MAC at booking. We approached all Caucasian women who met the inclusion criteria attending the University College Hospital, London between 1 April 1996 and 30 June 1997 and the Rotunda Hospital, Dublin, Ireland between 15 April 2003 and 19 May 2004. A total of 2,912 women agreed to participate in the research. The participants’ maternal height and weight were measured. Their BMI was calculated using the formula: BMI = weight (kg) ÷ height (m2). The MAC was measured in cm. Statistical analysis was performed using SPSS for Windows version 11 with p < 0.05 as significant. We found that BMI is directly correlated with MAC (r = 0.836) and estimates of BMI may be calculated from the simple equation BMI = MAC ± 2. Alternatively, a MAC of ≥ 27 cm allowed for a detection rate for overweight patients of 75%, with a false positive rate of 15%.

Circulating pro- and anticoagulant levels in normal and complicated primigravid pregnancies and their relationship to placental pathology

We aimed to compare the changes in factor VIII:C, antithrombin, protein C, protein S and fibrinogen in a cohort of low-risk primigravida who developed maternal or fetal complications to those who had uncomplicated pregnancies and to correlate these findings with placental pathology. This is a case–control study of 170 cases and 122 controls selected from a prospective cohort of 1,011 low-risk primigravida. Significantly elevated levels of factor VIII:C and significantly decreased levels of antithrombin were seen in women who developed pre-eclampsia (p <0.001), placental infarction (p < 0.001) or had infants with a birth weight < 3rd centile (p < 0.001). Placental villous dysmaturity was significantly associated with raised factor VIII:C (p < 0.001). Women who developed pre-eclampsia showed elevated fibrinogen at 14 weeks (p = 0.03). Significantly higher than normal pregnancy levels of factor VIII:C, in tandem with significantly lower antithrombin levels associated with certain adverse pregnancy outcomes, may be related to underlying placental insufficiency. This is supported by associated placental findings.

Ponderal index (PI) vs birth weight centiles in the low-risk primigravid population: Which is the better predictor of fetal wellbeing?

Our objective was to compare Ponderal index (PI) with birth weight centiles as predictors of perinatal morbidity and to determine which best reflects the presence of placental disease. We prospectively recruited 1,011 low-risk primigravidas and calculated PI and birth weight centiles following delivery. Perinatal morbidity was defined as: pre-term birth (PTB); fetal acidosis; an Apgar score < 7 at 5 min or neonatal resuscitation. Placental disease was defined as chronic uteroplacental insufficiency (CUPI); villous dysmaturity; infection or vascular pathology. Ponderal index was statistically reduced (25.33 vs 27.79 p = 0.001) and the incidence of infant birth weight < 9th centile was statistically higher (11.1% vs 5.1%; p = 0.004) in cases with PTB and in CUPI (26.23 vs 27.84; p = 0.001 and 28.2.1% vs 10.4%; p = 0.002). Both PI and infant birth weight centile < 9th centile for gestational age correlate with PTB, however overall, both are poor predictors of neonatal and placental disease.

The impact of positive acquired thrombophilia serology on ultrasound, obstetric outcome and the placenta in a low-risk primigravid population

Our aim was to determine the prevalence and sequelae of positive acquired thrombophilia serology in the asymptomatic low-risk primigravid population. We undertook a prospective blinded study of 1011 primigravid patients screening for lupus anticoagulant, anticardiolipin antibody, anti-β 2 glycoprotein-1 and antinuclear antibody assessment at booking and 36 weeks gestation. Serial ultrasounds of the fetus with uterine and umbilical Dopplers and placental evaluation were performed at 24 and 36 weeks gestation. Antenatal course, labour and delivery outcome and placental histology were reviewed. The incidence of positive acquired thrombophilia serology was 27.4%. Overall, there was no difference in rates of fetal loss or maternal disease between women with positive acquired thrombophilia serology and the control population. Routine testing for acquired thrombophilic traits is therefore not warranted.

Tubal abscess in pregnancy: A case report

A 28 year old woman Para 1 who had a previously uneventful full term normal delivery, presented at 25 weeks gestation with spontaneous rupture of membranes and generalized abdominal pain. She was hepatitis C positive. She was receiving 50 mls of methadone per day and had a history of intravenous drug abuse. On examination she had a pyrexia of 388C. Abdominal examination revealed generalized tenderness, rebound tenderness, guarding and palpable uterine contractions. Sterile speculum examination confirmed rupture of membranes. An offensive green discharge was noted. The cervix was fully effaced and 2 cm dilated. Ultrasound confirmed a breech presentation. Cardotocograph showed a baseline of 200 beats per minute. She underwent an emergency Caesarean section on the clinical suspicion of chorioamnionitis. A male infant weighing 0.67 kg delivered had agar score of 3 at 1 minute and 9 at 5 minutes. At caeserean section, 700 mls of offensive pus was found in the abdominal cavity. There were dense adhesions, and a large ruptured right-sided tubo-ovarian abscess. The left tube and ovary was normal. The abdominal cavity was washed out and a drain left in situ for 48 hrs. Triple intravenous antibiotics were commenced. Swabs from the peritoneal cavity revealed a Beta-hemolytic Streptococcus Lance field group C and mixed anaerobic bacteria were isolated from pus from the abdominal cavity. Blood cultures were negative. Swabs for Chlamydia were negative. Histopathological examination of the placenta showed evidence of ascending infection, acute supparative chorioamnionitis, funicitis and villous edema. She had a good postoperative recovery and both mother and baby did well. Discussion