A. Mahendru

Cardiovascular disease in menopause: does the obstetric history have any bearing?

Cardiovascular disease remains a leading cause of morbidity and mortality in menopausal women in spite of the overall reduction in age-adjusted mortality from the disease in the last few years. It is now clear that mechanisms of cardiovascular disease in menopausal women are similar to men and rather than midlife acceleration of cardiovascular disease in women, the final impact of cardiovascular disease in later life may be a reflection of cardiovascular changes during reproductive years as a result of woman’s obstetric history. A decade after the Women’s Health Initiative trial, there is upcoming evidence to suggest that hormone replacement therapy in young recently menopausal women has a cardioprotective effect. Cardiovascular changes during normal pregnancy or pregnancy complications such as preeclampsia may affect a woman’s long-term cardiovascular health. Therefore, it is plausible that the cardioprotective benefit of hormone replacement therapy depends on occult pre-existing cardiovascular risks in women in relation to their previous obstetric history. In this review, we describe the cardiovascular changes during and after pregnancy in obstetric complications such as recurrent miscarriage, preeclampsia, intrauterine growth restriction, preterm labour and gestational diabetes; existing evidence regarding their association with cardiovascular disease later in life, and hypothesize possible mechanisms. Our aim is to improve the understanding and highlight the importance of including obstetric history in risk assessment in menopausal women and individualizing their risks before prescribing hormone replacement therapy. Future research in risk benefit assessment of hormone replacement therapy should also account for a woman’s background cardiovascular risk in the light of her obstetric history.

OC10.01: Early pregnancy changes in maternal haemodynamics using pulse wave analysis

Objectives: The objective of our study was to determine the incidence of stillbirth in monochorionic twin pregnancies after 24 0/7 weeks gestational age in a large, unselected cohort of monochorionic (MC) twins. In addition, we sought to explore the added risk factor of twin-to-twin transfusion syndrome (TTTS) in this cohort. Methods: We completed a retrospective cohort study of all MC twin pregnancies in the Kaiser Northern California (KPNC) population delivered between 1996 and 2003. All twin placentas were submitted to pathology during this time frame, and chorionicity was confirmed by placental pathology. Pregnancies were excluded if delivery or termination occurred prior to 24 0/7 weeks’ gestation, birth data was unavailable or chorionicity could not be confirmed. The incidence of stillbirth, TTTS and outcomes for liveborn twins were assessed by database search and chart review. Results: From 1996–2003, 646 monochorionic twin sets were cared for and delivered by KPNC and 594 of these pregnancies met criteria for inclusion. Thirteen pregnancies resulted in the demise of both twins and 26 pregnancies resulted in the demise of a single twin, thus 4.4% of all infants delivered after 24 0/7 weeks’ gestation were stillborn (52/1188). 9.1% of MC pregnancies were affected by TTTS (54/594) and 25.9% of the TTTS pregnancies resulted in intrauterine fetal demise (IUFD) of at least one twin (14/54) compared to 4.6% of non-TTTS pregnancies (25/540). The RR for fetal demise after 24 weeks’ gestation in MC twins affected by TTTS is 4.86 (CI 2.86–8.59). Conclusions: In our study population, one in every fifteen MC twin pregnancies resulted in a post-viability IUFD of at least one twin. This incidence of IUFD appears higher than that of the general population, affirming the results of previous studies. Families should be counseled about these pregnancy prognoses and further prospective studies should be done to assess the optimal gestational age for delivery to potentially prevent these outcomes.

OP32.02: Relationship between ovulation‐implantation interval, first trimester crown‐rump length, birth weight and gestation at delivery

that may be compared across countries. Obstetric guidelines provide definitions of growth irregularities and Doppler abnormalities that rely on exact estimations of gestational age or date of delivery (EDD). Correspondingly, guidelines for how to treat preterm labor – or when to perform amniocentesis, give corticosteroids, or induce in post-term pregnancy, require reliable and uniform pregnancy dating. However, the dating models vary in predictive quality and there is no agreement on which dating model to use. The aim of this study was to evaluate a population-based dating model by comparing the model’s EDD prediction results on three different populations, in order to assess variations across the populations that might influence prediction bias. Methods: We included second-trimester measurements of biparietal diameter (BPD) and femur length (FL) from altogether 73,400 routine examinations performed at hospitals in three locations in Norway. The prediction model (‘eSnurra’) was applied to the ultrasound measurements, and the resulting EDD predictions were compared with the actual time of the subsequent deliveries. The difference (median bias) was calculated for each BPD/FL measurement value. Results: The predictions of EDD were mostly within ± 1 day from the actual date of delivery for all measurement values and in all three study populations. Conclusions: The Norwegian comprehensive education of sonographers that includes standardized measurement techniques, combined with a term prediction model based on an unselected, large population has resulted in a uniform and reliable dating of pregnancies across the country. If protocols dealing with pregnancy complications are to be of any clinical value, dating models must be quality assessed and standardized.

OC10.05: Early pregnancy changes in maternal arterial stiffness

R. Deshpande1,2, D. Anblagan4, N. W. Jones1,2, N. Raine-Fenning1, G. Bugg2, P. Mansell3, P. Gowland4, L. Leach3 1School of Clinical Sciences, Division of Human Development, University of Nottingham, Nottingham, United Kingdom; 2Deparment of Obstetrics & Gynecology, Queens Medical Centre, Nottingham, United Kingdom; 3School of Biomedical Sciences, University of Nottingham, Nottingham, United Kingdom; 4Sir Peter Mansfield MRI Centre, University of Nottingham, Nottingham, United Kingdom

OP36.05: Difference in pre-pregnancy arterial stiffness in women with previous severe pre-eclampsia/ IUGR and women with prior normal pregnancies

Objectives: To evaluate the correlation between fetal cerebral blood perfusion by fractional moving blood volume and the degree of fetal anemia in maternal red-cell alloimmunization fetuses selected by elevated middle cerebral artery Doppler (MCA). Methods: Cerebral blood perfusion measured by fractional moving blood volume (FMBV) was assessed in 16 consecutive fetuses with increased peak systolic velocity (PSV, > 1.5 MoM) in the MCA Doppler, and correlated with the presence (defined as hemoglobin levels < 0.84 MoM for gestational age) and degree of anemia at the time of cordocentesis. Results: Fetuses with confirmed anemia at cordocentesis showed significantly higher FMBV values than those with normal hemoglobin (39.9% vs. 22.9%, P = 0.01). Cerebral FMBV showed a significant negative correlation with the concentration of fetal hemoglobin (−0.62, P = 0.01) and a non-significant positive correlation with the PSV in the MCA Doppler (0.11, P = 0.69). The false positive rate of increased FMBV (above 2.0 MoM) and MCA-PSV was 8.0% and 31.3% for the diagnosis of fetal anemia, while it was 10% and 43.8%, for the diagnosis of severe fetal anemia, respectively. Conclusions: Increased cerebral tissue perfusion might decrease the false positive rate of the middle cerebral artery Doppler for the diagnosis of fetal anemia in maternal red cell alloimmunization.

OP02.05: Ovulation‐implantation interval in relation to early pregnancy outcome

Objectives: To determine the variables associated with different outcomes for pregnancies of unknown location (PUL). Methods: Prospective observational study. Women in the 1st trimester of pregnancy presenting to the early pregnancy unit (EPU), between 2009 and March 2011, underwent a transvaginal scan (TVS). A PUL was classified on TVS if there was no intraor extra-uterine pregnancy. Data was collected from women with a PUL at the first TVS. More than 10 historical, clinical and 3-D ultrasonographic end points were collected for analysis. Women were followed up until the outcome was established: failed PUL, intrauterine pregnancy (IUP) and ectopic pregnancy (EP). Off-line 3-D processing of the uterine and ovarian volumes was performed using VOCAL in order to calculate endometrial volume (EV), mean gray index, vascular index (VI), flow index (FI) and vascular flow index (VFI). Univariate analysis was performed in order to establish the significant variables for the different PUL outcomes (ANOVA F-test and Fisher’s exact test). Results: 154 women were initially classified as a PUL. 143 women were included in the final analysis (11 cases lost to follow up). 69.2% (99/143) failed PULs, 23.1% (33/143) IUPs and 7.7% (11/143) EPs. The variables that were significantly associated with PUL outcomes were: gray index (P = 0.01), flow index (P = 0.01), hCG at 48hrs (P = 3.13E-07), log hCG at 48hrs (P = 1.89E-09), and hCG ratio (P = 4.34E-16). Conclusions: 3-D volumetric indices of the uterus and ovary may be useful in the prediction of PUL outcome. These results could result in the development of new mathematical models in management of PULs.