Prophylaxis and treatment of thrombophilia in pregnancy

The Pregnant Patient - Why Do My Feet Hurt?

Although hormonal and anatomical changes that occur during pregnancy have been well documented, how these changes affect foot and ankle function are less understood. Changes during pregnancy in body mass, body-mass distribution, joint laxity, and muscle strength can all contribute to alterations in gait pattern that can lead to pain or injury to the foot and ankle. This review provides an overview of the various foot and ankle anatomic, biomechanic, and kinematic changes that occur during pregnancy. In addition, this article presents the most common causes of foot and ankle symptoms expressed by the pregnant patient population and discuss the management and treatment of each condition.

Ovarian vein thrombosis

Ovarian vein thrombosis (OVT) is a rare cause of abdominal pain that may mimic a surgical abdomen. It is most often diagnosed during the postpartum period. In this report, we present four cases of postoperative ovarian vein thrombosis. The complications of OVT can be significant, and the diagnosis relies on a careful examination of the radiographic findings. It can occur with lower quadrant abdominal pain, especially in the setting of recent pregnancy, abdominal surgery, pelvic inflammatory disease, or malignancy. Diagnosis can be made with confidence using ultrasound, computed tomography or magnetic resonance imaging. Treatment of ovarian vein thrombosis is particularly important in the post-partum patients, with anticoagulation therapy being the current recommendation.

HEPARIN IN HUMAN PLACENTAL DEVELOPMENT AND THE PREVENTION OF PLACENTAL COMPLICATIONS OF PREGNANCY

The development of effective anticoagulant drugs available for use in pregnancy has resulted in dramatic improvements for a number of potentially life-threatening conditions. These include the treatment and prevention of venous thromboembolism and the thrombotic complications of antiphospholipid antibody syndrome, as well as the management of pregnant women with mechanical heart valves. The most commonly used class of drug includes heparin, a highly-charged macro-molecule that does not cross the placenta, in contrast to the potentially teratogenic and fetotoxic oral drug warfarin. This review will focus on our current lack of understanding of the wider actions of heparin and examines the possibility that large numbers of pregnant women are presently being treated inappropriately with heparin.

Maternal thrombophilia and the risk of recurrence of preeclampsia

OBJECTIVE

The aim of this prospective study was to determine the impact of thrombophilia on the recurrence of preeclampsia.

STUDY DESIGN

In a multicenter, observational, cohort design, 172 white patients with a previous pregnancy complicated by preeclampsia were observed in the next pregnancy. They were evaluated for heritable thrombophilia (factor V Leiden and factor II G20210A mutations, protein S, protein C, and antithrombin deficiency), hyperhomocystinemia, lupus anticoagulant, and anticardiolipin antibodies. Development of preeclampsia and maternal complications and both gestational age at delivery and birthweight were recorded.

RESULTS

Sixty women (34.9%) showed the presence of a thrombophilic defect. They had a higher risk for the recurrence of preeclampsia (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.2-5.1), compared to patients without thrombophilia. Similar findings were observed considering only heritable thrombophilia. Thrombophilic patients were at increased risk for the occurrence of very early preterm delivery (< 32 weeks; OR, 11.6; 95% CI, 3.4-43.2).

CONCLUSION

When counseling white women with a history of preeclampsia, screening for thrombophilia can be useful for preconceptional counseling and pregnancy management.

A likelihood model that accounts for censoring due to fetal loss can accurately test the effects of maternal and fetal genotype on the probability of miscarriage

OBJECTIVE

Heritable maternal and fetal thrombophilia and/or hypofibrinolysis are important causes of miscarriage. Under the constraint that fetal genotype is observed only after a live birth, estimating risk is complicated. Censoring prevents use of published statistical methodology. We propose techniques to determine whether increases in miscarriage are due to the fetal genotype, maternal genotype, or both.

METHODS

We propose a study to estimate the risk of miscarriage contributed by an allele, expressed in either dominant or recessive fashion. Using a multinomial likelihood, we derive maximum likelihood estimates of risk for different genotype groups. We describe likelihood ratio tests and a planned hypothesis testing strategy.

RESULTS

Parameter estimation is accurate (bias <0.0011, root mean squared error <0.0780, n = 500). We used simulation to estimate power for studies of three gene mutations: the 4G hypofibrinolytic mutation in the plasminogen activator inhibitor gene (PAI-1), the prothrombin G20210A mutation, and the Factor V Leiden mutation. With 500 families, our methods have approximately 90% power to detect an increase in the miscarriage rate of 0.2, above a background rate of 0.2.

CONCLUSION

Our statistical method can determine whether increases in miscarriage are due to fetal genotype, maternal genotype, or both despite censoring.

Operative fixation of acetabular fractures in the pregnant patient

OBJECTIVE

To describe in utero radiation exposures in pregnant patients undergoing acetabular fracture repair.

DESIGN

Retrospective case series.

SETTING

University-affiliated regional trauma center.

PATIENT/PARTICIPANTS

Eight pregnant patients with acetabular fractures treated over a 6-year period. There were an additional 518 acetabular fractures in nonpregnant patients treated during the same time period.

INTERVENTION

Open reduction and internal fixation of the acetabulum fracture.

OUTCOME MEASUREMENTS

None. This is a descriptive series reporting fetal radiation doses, fetal fluoroscopy exposure times, and fetal viability after treatment.

RESULTS

The gestational age of the fetuses at presentation ranged from 5 to 26 weeks. Infant delivery averaged 27 weeks from the time of surgery and all pregnancies reached 36 weeks. Apgar scores were normal each child including 1 twin delivery. There were 4 posterior wall fractures, 3 transverse or posterior wall fractures, and 1 posterior column fracture. Intraoperative pelvic fluoroscopy averaged 39 seconds. There were no operative complications and fracture reductions were anatomic in 7 patients. Computed tomography scan of the pelvis conferred the greatest exposure risk to the fetus and fluoroscopy conferred the least. In each case that required a computed tomography scan of the pelvis, the calculated radiation exposure dose to the fetus was greater than 5 cGy.

CONCLUSIONS

The results of this study demonstrate that with a team approach and the judicious use of radiographic imaging during the surgical care of a displaced acetabular fracture in the pregnant patient, minimal risk to the baby can be achieved in pursuit of acceptable articular reductions.

Usefulness of a placental profile in high-risk pregnancies

OBJECTIVE

Test the hypothesis that a placental function profile can reassure most high-risk women with normal test results yet accurately can identify a subset of women who are destined for major complications that will be attributable to placental disease.

STUDY DESIGN

This was a prospective study of 212 high-risk pregnancies that used the placental profile (16- to 18-week maternal serum screening, 18- to 23-week uterine artery Doppler imaging, and placental morphologic condition). Odds ratios (95% CI) were derived for intrauterine fetal death (IUFD), preterm delivery at < 34 weeks of gestation, preeclampsia/hemolysis, elevated liver enzymes, and low platelet count syndrome (HELLP) syndrome, small for gestational age delivery, and early-onset intrauterine growth restriction (IUGR); all normal test results (n =125) were compared with > or = 1 abnormal test results.

RESULTS

The odds of the development of adverse outcomes were significantly less in women with all normal test results (preeclampsia/HELLP [odds ratio, 0.2; 95% CI, 0.1-0.4]), preterm delivery (odds ratio, 0.1; 95% CI, 0.06-0.3), small for gestational age delivery (odds ratio, 0.2; 95% CI, 0.09-0.3), early-onset IUGR (0), and IUFD (odds ratio, 0.05 [0.01-0.2]). Combining those women with two (n = 21) of 3 (n = 15) abnormal test results together predicted 14 of 19 severe IUGR and 15 of 22 IUFD cases.

CONCLUSION

This placental function profile at 16-23 weeks of gestation can reassure women with normal test results by identifying a smaller subset of women who are at reduced risk of perinatal morbidity or death from severe IUGR.